AP Biology Flashcards: Complete 8-Unit Course Review
Review all 8 AP Biology units with original flashcards for concepts, pathways, experimental design, data interpretation, and FRQ reasoning.
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AP Biology Flashcards: Complete 8-Unit Course Review
The current AP Biology framework covers eight units, from chemistry of life through ecology. This 540-card deck turns that full course into short, original retrieval prompts, with science-practice reasoning mixed into the biology instead of parked in a separate section.
What the cards practice
The cards connect terms to functions, structures to consequences, pathway steps to inputs, outputs, locations, and regulation, and evidence to biological claims. Separate prompts cover useful reverse mappings when they are real study tasks—for example, identifying a process from its location or choosing the inference supported by a result. Short original scenarios also practice describing patterns, explaining mechanisms, predicting changes, justifying claims, setting up calculations, and evaluating evidence.
The deck does not mechanically reverse every definition or pathway. It leaves out copied exam material, scoring language, official figures, exhaustive protocols, broad essay prompts, textbook-specific trivia, and advanced-college details outside the current course boundary.
Learning order
The sequence follows Units 1–8. Within each unit it moves from prerequisites to processes, applications, experiments, data, and FRQ-style reasoning, while spacing close variants apart. Long-term spacing and interleaving are left to the review scheduler.
What still needs practice
Flashcards are useful for recall and small reasoning moves, but they cannot replace laboratory work, graph construction, extended data analysis, or timed multiple-choice and free-response practice. Use the deck beside class labs and full original practice questions.
Scope and provenance
The course boundary was reviewed on September 1, 2026 against the College Board AP Biology course page, the Fall 2025 Course and Exam Description, its current clarifications and corrections, the 2026–27 course-change table, and the current exam page. The selection, prompts, answers, examples, sequence, metadata, and cover are independently created from common biological knowledge and source checks. No exam questions, scoring guidelines, CED text, answer keys, or official figures were copied or transformed.
The Common knowledge · CC0 1.0 label applies to the original wording, organization, metadata, and generated media to the extent applicable rights exist. It does not claim ownership of biological facts, AP or College Board names, or third-party source material.
This independent, unofficial study deck is not affiliated with, endorsed by, or sponsored by College Board. AP and College Board names identify the course and exam only. Official requirements: https://apcentral.collegeboard.org/courses/ap-biology
Kartu dalam dek ini
Kartu 1
Pertanyaan
Why is a water molecule polar?
Jawaban
Oxygen pulls shared electrons more strongly than hydrogen, giving oxygen a partial negative charge and the hydrogens partial positive charges.
Kartu 2
Pertanyaan
Which elements make up most biological molecules?
Jawaban
Carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur—often shortened to CHNOPS.
Kartu 3
Pertanyaan
What is the relationship between a monomer and a polymer?
Jawaban
Monomers are small building blocks; polymers are chains or networks made from repeated monomers.
Kartu 4
Pertanyaan
What is a monosaccharide's main role in cells?
Jawaban
It can provide quick energy and serve as a building block for larger carbohydrates.
Kartu 5
Pertanyaan
Why do lipids mix poorly with water?
Jawaban
Most of their bonds are nonpolar, so water cannot form favorable interactions with them.
Kartu 6
Pertanyaan
What three parts make up a nucleotide?
Jawaban
A five-carbon sugar, a phosphate group, and a nitrogenous base.
Kartu 7
Pertanyaan
What parts of an amino acid vary and stay constant?
Jawaban
The amino group, carboxyl group, hydrogen, and central carbon are shared; the side chain, or R group, varies.
Kartu 8
Pertanyaan
What does pH measure?
Jawaban
The negative logarithm of hydrogen-ion concentration; lower pH means more hydrogen ions.
Kartu 9
Pertanyaan
What is a hydrogen bond in liquid water?
Jawaban
A weak attraction between a partially positive hydrogen on one water molecule and a partially negative oxygen on another.
Kartu 10
Pertanyaan
How does an unsaturated fatty acid differ from a saturated one?
Jawaban
An unsaturated fatty acid has at least one carbon–carbon double bond; a saturated fatty acid has none.
Kartu 11
Pertanyaan
What bond links amino acids in a polypeptide?
Jawaban
A peptide bond.
Kartu 12
Pertanyaan
What does dehydration synthesis do?
Jawaban
It joins subunits with a covalent bond while removing the elements of water.
Kartu 13
Pertanyaan
How does cohesion help water move through a plant?
Jawaban
Hydrogen bonds keep water molecules linked, helping a continuous column rise through xylem.
Kartu 14
Pertanyaan
How do plants and animals differ in short-term glucose storage?
Jawaban
Plants store glucose mainly as starch; animals store it mainly as glycogen.
Kartu 15
Pertanyaan
What determines a protein's primary structure?
Jawaban
Its amino-acid sequence.
Kartu 16
Pertanyaan
How does a cis double bond affect a fatty-acid tail?
Jawaban
It introduces a bend that prevents neighboring tails from packing tightly.
Kartu 17
Pertanyaan
How does adhesion support water transport in narrow tubes?
Jawaban
Water sticks to polar surfaces, helping it resist gravity along cell walls.
Kartu 18
Pertanyaan
Which base pairing distinguishes RNA from DNA?
Jawaban
RNA uses uracil, so adenine pairs with uracil instead of thymine.
Kartu 19
Pertanyaan
What stabilizes common protein secondary structures?
Jawaban
Hydrogen bonds between atoms in the polypeptide backbone.
Kartu 20
Pertanyaan
Why can carbon form so many biological structures?
Jawaban
It has four valence electrons and can form four stable covalent bonds, including chains, branches, and rings.
Kartu 21
Pertanyaan
Why can some insects stand on water?
Jawaban
Cohesion among surface water molecules creates high surface tension.
Kartu 22
Pertanyaan
What does hydrolysis do to a biological polymer?
Jawaban
It adds the elements of water to break a covalent bond between subunits.
Kartu 23
Pertanyaan
What carbohydrate strengthens plant cell walls?
Jawaban
Cellulose.
Kartu 24
Pertanyaan
Why are fats useful for long-term energy storage?
Jawaban
Their many C–H bonds store substantial chemical energy, and hydrophobic storage adds little water mass.
Kartu 25
Pertanyaan
How does water buffer rapid temperature change?
Jawaban
Breaking and forming many hydrogen bonds absorbs or releases substantial heat, giving water a high specific heat.
Kartu 26
Pertanyaan
What does antiparallel mean for a DNA double helix?
Jawaban
Its two strands run in opposite directions: one 5′→3′ and the other 3′→5′.
Kartu 27
Pertanyaan
What mainly drives a protein's tertiary structure?
Jawaban
Interactions among side chains, including hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges.
Kartu 28
Pertanyaan
What is a trace element?
Jawaban
An element an organism needs in very small amounts, such as iron in many electron-transfer proteins.
Kartu 29
Pertanyaan
Why does sweating cool an organism?
Jawaban
The fastest water molecules escape as vapor, carrying heat away from the surface.
Kartu 30
Pertanyaan
A cell builds a polysaccharide from sugars. Is water consumed or released?
Jawaban
Released. Forming each linkage by dehydration removes water.
Kartu 31
Pertanyaan
Why can branching help a storage polysaccharide release glucose quickly?
Jawaban
More branch ends give enzymes more sites to work at once.
Kartu 32
Pertanyaan
What makes a phospholipid amphipathic?
Jawaban
It has a polar, hydrophilic head and nonpolar, hydrophobic tails.
Kartu 33
Pertanyaan
Where is biological information encoded in a nucleic acid?
Jawaban
In the linear sequence of nucleotide bases.
Kartu 34
Pertanyaan
What is quaternary protein structure?
Jawaban
The arrangement of two or more polypeptide subunits into one functional protein.
Kartu 35
Pertanyaan
Why does ice float on liquid water?
Jawaban
Stable hydrogen bonds hold ice molecules in an open lattice, making ice less dense than liquid water.
Kartu 36
Pertanyaan
How does electronegativity affect a covalent bond?
Jawaban
A difference in attraction for electrons makes electron sharing unequal and can create a polar bond.
Kartu 37
Pertanyaan
A digestive reaction adds water while splitting a macromolecule. What reaction is this?
Jawaban
Hydrolysis.
Kartu 38
Pertanyaan
What links monosaccharides in a polysaccharide?
Jawaban
Glycosidic covalent bonds.
Kartu 39
Pertanyaan
Why do phospholipids form bilayers in water?
Jawaban
Hydrophilic heads face water while hydrophobic tails cluster away from it.
Kartu 40
Pertanyaan
To which end are nucleotides added during nucleic-acid synthesis?
Jawaban
The 3′ end of the growing strand.
Kartu 41
Pertanyaan
Why can one amino-acid substitution change protein function?
Jawaban
It can alter side-chain interactions, folding, stability, or an active or binding site.
Kartu 42
Pertanyaan
How does a buffer resist a pH change?
Jawaban
It can accept added hydrogen ions or donate them when hydrogen-ion concentration falls.
Kartu 43
Pertanyaan
Why is water a useful solvent for cells?
Jawaban
Its partial charges surround ions and other polar molecules, separating and dispersing them.
Kartu 44
Pertanyaan
Why do functional groups matter in organic molecules?
Jawaban
They give carbon skeletons predictable chemical properties, such as polarity, acidity, or reactivity.
Kartu 45
Pertanyaan
Why can two polymers built from similar monomers have different functions?
Jawaban
Their monomer sequence, branching, length, and three-dimensional shape can differ.
Kartu 46
Pertanyaan
A seedling consumes stored starch. What happens to the starch?
Jawaban
Hydrolysis breaks it into smaller sugars that can enter energy pathways.
Kartu 47
Pertanyaan
What are two biological roles of steroids?
Jawaban
Some act as signaling molecules, and cholesterol helps stabilize animal cell membranes.
Kartu 48
Pertanyaan
What bond forms the backbone of a nucleic-acid strand?
Jawaban
Covalent phosphodiester bonds link the sugar of one nucleotide to the phosphate of the next.
Kartu 49
Pertanyaan
What does denaturation do to a protein?
Jawaban
It disrupts the protein's three-dimensional shape and often its function without usually breaking the primary peptide chain.
Kartu 50
Pertanyaan
An enzyme works best near pH 7 but slows at pH 3. What is a likely explanation?
Jawaban
Extra hydrogen ions changed charges and interactions that maintain the enzyme's active shape.
Kartu 51
Pertanyaan
What structure encloses every cell?
Jawaban
A plasma membrane.
Kartu 52
Pertanyaan
What is the nucleus's main function?
Jawaban
It houses most eukaryotic DNA and is a major site of DNA replication and transcription.
Kartu 53
Pertanyaan
Why does surface-area-to-volume ratio fall as a cell grows?
Jawaban
Volume increases with the cube of length, while surface area increases with the square.
Kartu 54
Pertanyaan
What does the fluid mosaic model describe?
Jawaban
A dynamic phospholipid bilayer containing mobile proteins, sterols, and carbohydrates.
Kartu 55
Pertanyaan
What drives simple diffusion?
Jawaban
Random molecular motion produces net movement from higher to lower concentration.
Kartu 56
Pertanyaan
How does active transport differ from facilitated diffusion?
Jawaban
Active transport moves a substance against its gradient using energy; facilitated diffusion moves it down a gradient.
Kartu 57
Pertanyaan
Why does compartmentalization increase cellular efficiency?
Jawaban
It concentrates enzymes and substrates and maintains distinct conditions for different reactions.
Kartu 58
Pertanyaan
When should a light microscope be preferred over an electron microscope?
Jawaban
When observing living cells or dynamic processes at lower resolution.
Kartu 59
Pertanyaan
What does the nucleolus produce?
Jawaban
Ribosomal RNA and early ribosome subunits.
Kartu 60
Pertanyaan
Does passive transport require direct cellular energy?
Jawaban
No. It moves substances down an electrochemical or concentration gradient.
Kartu 61
Pertanyaan
What feature separates prokaryotic from eukaryotic cells?
Jawaban
Eukaryotic cells have a membrane-bound nucleus and other membrane-bound organelles; prokaryotic cells do not.
Kartu 62
Pertanyaan
Which membrane region blocks most ions and polar molecules?
Jawaban
The hydrophobic interior formed by phospholipid tails.
Kartu 63
Pertanyaan
What happens on rough endoplasmic reticulum?
Jawaban
Bound ribosomes make proteins for secretion, membranes, or the endomembrane system.
Kartu 64
Pertanyaan
How does facilitated diffusion differ from simple diffusion?
Jawaban
It uses a channel or carrier protein but still moves a substance down its gradient.
Kartu 65
Pertanyaan
Where is prokaryotic DNA usually located?
Jawaban
In a nucleoid region rather than inside a membrane-bound nucleus.
Kartu 66
Pertanyaan
How does cholesterol affect an animal membrane?
Jawaban
It buffers fluidity, limiting excess movement when warm and preventing tight packing when cool.
Kartu 67
Pertanyaan
What does smooth endoplasmic reticulum do?
Jawaban
It synthesizes lipids, detoxifies some compounds, and stores calcium in specialized cells.
Kartu 68
Pertanyaan
What determines a channel protein's selectivity?
Jawaban
Its pore size, shape, charge, and gating behavior.
Kartu 69
Pertanyaan
What does the sodium–potassium pump accomplish?
Jawaban
Using ATP, it exports three sodium ions and imports two potassium ions per cycle.
Kartu 70
Pertanyaan
What do ribosomes do in both prokaryotic and eukaryotic cells?
Jawaban
They translate mRNA into polypeptides.
Kartu 71
Pertanyaan
What is the Golgi apparatus's role?
Jawaban
It modifies, sorts, and packages proteins and lipids arriving from the endoplasmic reticulum.
Kartu 72
Pertanyaan
What is osmosis?
Jawaban
Net movement of water across a selectively permeable membrane toward lower free-water concentration.
Kartu 73
Pertanyaan
Why does a high surface-area-to-volume ratio help a cell?
Jawaban
It provides more membrane area per unit of cytoplasm for exchange with the environment.
Kartu 74
Pertanyaan
How do unsaturated phospholipid tails affect membrane fluidity?
Jawaban
Their bends reduce tight packing, usually increasing fluidity.
Kartu 75
Pertanyaan
Trace a secreted protein after translation begins.
Jawaban
Rough ER → transport vesicle → Golgi → secretory vesicle → plasma membrane.
Kartu 76
Pertanyaan
What happens to an animal cell in a hypotonic solution?
Jawaban
Water enters; the cell swells and may lyse.
Kartu 77
Pertanyaan
What is cotransport?
Jawaban
The downhill movement of one substance powers the uphill transport of another through the same protein.
Kartu 78
Pertanyaan
What is the main role of a cell wall?
Jawaban
It provides structural support and helps prevent excessive expansion.
Kartu 79
Pertanyaan
What do lysosomes do?
Jawaban
Their hydrolytic enzymes digest macromolecules and recycle damaged cell parts in an acidic compartment.
Kartu 80
Pertanyaan
What happens to an animal cell in a hypertonic solution?
Jawaban
Water leaves; the cell shrinks.
Kartu 81
Pertanyaan
How do intestinal microvilli improve absorption?
Jawaban
They increase membrane surface area without greatly increasing cell volume.
Kartu 82
Pertanyaan
What can an integral membrane protein do?
Jawaban
It can transport substances, receive signals, catalyze reactions, or anchor cell structures.
Kartu 83
Pertanyaan
What is a central vacuole's major role in a plant cell?
Jawaban
It stores solutes and water and helps maintain turgor pressure.
Kartu 84
Pertanyaan
What happens to a plant cell in a hypotonic solution?
Jawaban
Water enters and turgor pressure rises; the cell wall helps prevent bursting.
Kartu 85
Pertanyaan
How can a proton gradient power sucrose uptake in a plant cell?
Jawaban
Protons flow down their gradient through a symporter that carries sucrose uphill.
Kartu 86
Pertanyaan
What evidence supports the endosymbiotic origin of mitochondria?
Jawaban
They have double membranes, circular DNA, bacterial-like ribosomes, and divide independently by a similar process.
Kartu 87
Pertanyaan
Which overall energy-conversion pathway mainly occurs in mitochondria?
Jawaban
Most stages of aerobic cellular respiration and ATP production.
Kartu 88
Pertanyaan
What happens to a plant cell in a hypertonic solution?
Jawaban
Water leaves, turgor falls, and the membrane may pull from the wall during plasmolysis.
Kartu 89
Pertanyaan
Why can't a standard light microscope resolve a ribosome clearly?
Jawaban
A ribosome is smaller than the microscope's diffraction-limited resolution.
Kartu 90
Pertanyaan
How do bacterial and plant cell walls differ?
Jawaban
Bacterial walls usually contain peptidoglycan; plant walls contain cellulose.
Kartu 91
Pertanyaan
Which overall energy-conversion pathway occurs in chloroplasts?
Jawaban
Photosynthesis: converting light energy into chemical energy and fixing carbon.
Kartu 92
Pertanyaan
A cubical cell doubles each side length. How do surface area and volume change?
Jawaban
Surface area increases 4-fold; volume increases 8-fold.
Kartu 93
Pertanyaan
What is the role of membrane carbohydrates?
Jawaban
They help cells recognize and interact with one another.
Kartu 94
Pertanyaan
What is water potential?
Jawaban
A measure predicting water movement; water moves from higher to lower water potential.
Kartu 95
Pertanyaan
How do microtubules support a cell?
Jawaban
They resist compression, form tracks for motors, and build structures such as spindles, cilia, and flagella.
Kartu 96
Pertanyaan
What is endocytosis?
Jawaban
The plasma membrane folds inward to bring material into the cell in a vesicle.
Kartu 97
Pertanyaan
What evidence supports the endosymbiotic origin of chloroplasts?
Jawaban
They share bacterial-like DNA, ribosomes, division, and a double membrane consistent with engulfment.
Kartu 98
Pertanyaan
In a membrane-permeability test, what is the independent variable?
Jawaban
The factor deliberately changed, such as temperature or solute identity.
Kartu 99
Pertanyaan
How do microfilaments support cell movement?
Jawaban
Actin filaments interact with motor proteins to change cell shape, contract, and move materials.
Kartu 100
Pertanyaan
What does the cytosol contain?
Jawaban
Water, ions, small molecules, and proteins where many metabolic reactions occur.
Kartu 101
Pertanyaan
Why can diffusion limit cell size?
Jawaban
As dimensions grow, molecules must travel farther, while exchange area does not keep pace with metabolic volume.
Kartu 102
Pertanyaan
What does selective permeability mean?
Jawaban
The membrane allows some substances to cross more readily than others.
Kartu 103
Pertanyaan
What is an intermediate filament's general role?
Jawaban
It provides durable mechanical strength and helps anchor structures.
Kartu 104
Pertanyaan
How does adding a nonpenetrating solute affect water potential?
Jawaban
It makes solute potential, and usually total water potential, more negative.
Kartu 105
Pertanyaan
What is exocytosis?
Jawaban
A vesicle fuses with the plasma membrane and releases contents outside the cell.
Kartu 106
Pertanyaan
Why can lysosomal enzymes digest safely inside a cell?
Jawaban
A membrane isolates the acidic enzymes from most cytosolic components.
Kartu 107
Pertanyaan
Why include an untreated membrane sample in an experiment?
Jawaban
It provides a control baseline for judging the treatment's effect.
Kartu 108
Pertanyaan
Why doesn't cell size alone identify whether a cell is prokaryotic?
Jawaban
Sizes overlap; the presence or absence of internal membrane-bound structures is stronger evidence.
Kartu 109
Pertanyaan
Why are organelle interactions important?
Jawaban
Cell functions often require products to move through several specialized compartments rather than one organelle working alone.
Kartu 110
Pertanyaan
What graph would show a size constraint clearly?
Jawaban
Plot cell size on the x-axis and surface-area-to-volume ratio on the y-axis; the ratio should decline as size rises.
Kartu 111
Pertanyaan
Which molecules cross a phospholipid bilayer most easily without proteins?
Jawaban
Small nonpolar molecules, such as oxygen and carbon dioxide.
Kartu 112
Pertanyaan
Two solutions have equal water potential. What is the net water movement?
Jawaban
None, although water molecules still move both ways.
Kartu 113
Pertanyaan
Why is ATP loss likely to disrupt ion balance?
Jawaban
ATP-powered pumps stop maintaining gradients, so passive leaks move ions toward equilibrium.
Kartu 114
Pertanyaan
How does folding an internal membrane help an organelle?
Jawaban
It increases surface area for membrane-bound reactions without a matching increase in volume.
Kartu 115
Pertanyaan
A dye leaves heated cells faster than unheated cells. What conclusion is supported?
Jawaban
Heating increased membrane permeability under the tested conditions; the data alone do not identify the exact molecular damage.
Kartu 116
Pertanyaan
What does an enzyme change in a reaction?
Jawaban
It lowers activation energy, increasing reaction rate without changing the reaction's overall free-energy change.
Kartu 117
Pertanyaan
What makes a reaction exergonic?
Jawaban
It releases free energy and has a negative change in free energy under the stated conditions.
Kartu 118
Pertanyaan
What are the overall inputs and outputs of photosynthesis?
Jawaban
Carbon dioxide and water use light energy to produce carbohydrate and oxygen.
Kartu 119
Pertanyaan
What are the overall reactants and products of aerobic cellular respiration?
Jawaban
Organic fuel and oxygen are converted mainly to carbon dioxide, water, and ATP, with heat released.
Kartu 120
Pertanyaan
How should reaction rate be calculated from product data?
Jawaban
Divide the change in product amount by the elapsed time.
Kartu 121
Pertanyaan
What makes an enzyme substrate-specific?
Jawaban
The active site's shape and chemical properties favor particular substrates.
Kartu 122
Pertanyaan
Where do the light reactions occur?
Jawaban
In the thylakoid membranes of chloroplasts.
Kartu 123
Pertanyaan
Where does glycolysis occur?
Jawaban
In the cytosol.
Kartu 124
Pertanyaan
What makes a reaction endergonic?
Jawaban
It requires a net input of free energy and has a positive change in free energy.
Kartu 125
Pertanyaan
What is induced fit?
Jawaban
Substrate binding shifts the enzyme's shape into a form that better supports catalysis.
Kartu 126
Pertanyaan
Where does the Calvin cycle occur?
Jawaban
In the chloroplast stroma.
Kartu 127
Pertanyaan
What does glycolysis produce per glucose?
Jawaban
Two pyruvate, a net two ATP, and two NADH.
Kartu 128
Pertanyaan
How can cells drive an endergonic reaction?
Jawaban
They couple it to a sufficiently exergonic reaction so the combined free-energy change is negative.
Kartu 129
Pertanyaan
Why isn't an enzyme consumed by the reaction it catalyzes?
Jawaban
It returns to a reusable form after products leave the active site.
Kartu 130
Pertanyaan
What do photosynthetic pigments do?
Jawaban
They absorb particular wavelengths and transfer excitation energy into the light reactions.
Kartu 131
Pertanyaan
Does glycolysis require oxygen directly?
Jawaban
No. It can run without oxygen if NAD⁺ is regenerated.
Kartu 132
Pertanyaan
What does ATP hydrolysis commonly provide?
Jawaban
Usable free energy and a phosphate group that can change a molecule's reactivity or protein shape.
Kartu 133
Pertanyaan
How does substrate concentration affect rate at low concentrations?
Jawaban
Rate usually rises because more substrate molecules collide with available active sites.
Kartu 134
Pertanyaan
Why do chlorophyll-containing leaves reflect green light?
Jawaban
Chlorophyll absorbs green wavelengths less strongly than red and blue wavelengths.
Kartu 135
Pertanyaan
Where does pyruvate oxidation occur in a eukaryotic cell?
Jawaban
In the mitochondrial matrix.
Kartu 136
Pertanyaan
Why is ATP called an energy-coupling molecule?
Jawaban
Its hydrolysis links energy-releasing processes to cellular work.
Kartu 137
Pertanyaan
Why does enzyme rate plateau at high substrate concentration?
Jawaban
Most active sites are occupied, so enzyme amount becomes limiting.
Kartu 138
Pertanyaan
What is photolysis of water?
Jawaban
Light-driven splitting of water that supplies electrons and protons and releases oxygen.
Kartu 139
Pertanyaan
What happens during pyruvate oxidation?
Jawaban
Each pyruvate becomes acetyl-CoA, releasing carbon dioxide and reducing NAD⁺ to NADH.
Kartu 140
Pertanyaan
Why measure an initial enzyme rate?
Jawaban
Substrate depletion and product buildup have had less time to distort the rate.
Kartu 141
Pertanyaan
How can high temperature reduce enzyme activity?
Jawaban
Heat can disrupt interactions that maintain the enzyme's functional shape.
Kartu 142
Pertanyaan
What is photosystem II's key contribution?
Jawaban
It excites electrons and replaces them by oxidizing water.
Kartu 143
Pertanyaan
Where does the citric acid cycle occur in eukaryotes?
Jawaban
In the mitochondrial matrix.
Kartu 144
Pertanyaan
What is oxidation?
Jawaban
Loss of electrons, often accompanied by loss of hydrogen or gain of oxygen.
Kartu 145
Pertanyaan
Why does each enzyme have an optimal pH range?
Jawaban
pH changes charges on amino-acid side chains and can alter binding or folding.
Kartu 146
Pertanyaan
What does the photosynthetic electron transport chain build?
Jawaban
A proton gradient across the thylakoid membrane.
Kartu 147
Pertanyaan
What is the citric acid cycle's main energy role?
Jawaban
It oxidizes acetyl groups and transfers electrons to NADH and FADH₂, making a small amount of ATP.
Kartu 148
Pertanyaan
In a photosynthesis experiment, why keep leaf area constant?
Jawaban
Leaf area affects light capture and gas exchange, so changing it could confound the tested factor.
Kartu 149
Pertanyaan
How does a competitive inhibitor reduce enzyme activity?
Jawaban
It competes with substrate for the active site.
Kartu 150
Pertanyaan
How does chloroplast ATP synthase make ATP?
Jawaban
Protons flow from the thylakoid space to the stroma through ATP synthase, driving phosphorylation of ADP.
Kartu 151
Pertanyaan
Where is the respiratory electron transport chain located in eukaryotes?
Jawaban
In the inner mitochondrial membrane.
Kartu 152
Pertanyaan
What is reduction?
Jawaban
Gain of electrons, often accompanied by gain of hydrogen or loss of oxygen.
Kartu 153
Pertanyaan
How can extra substrate weaken competitive inhibition?
Jawaban
More substrate increases the chance that substrate, rather than inhibitor, occupies the active site.
Kartu 154
Pertanyaan
What is photosystem I's key contribution?
Jawaban
It re-energizes electrons used to reduce NADP⁺ to NADPH.
Kartu 155
Pertanyaan
What is oxygen's role in aerobic respiration?
Jawaban
It is the final electron acceptor and combines with electrons and protons to form water.
Kartu 156
Pertanyaan
A respiration graph gets steeper after temperature rises. What does the slope show?
Jawaban
A higher rate of the measured respiratory change, such as oxygen consumption per unit time.
Kartu 157
Pertanyaan
How does a noncompetitive inhibitor act?
Jawaban
It binds away from the active site and changes enzyme activity, often by altering shape.
Kartu 158
Pertanyaan
What products of the light reactions feed the Calvin cycle?
Jawaban
ATP and NADPH.
Kartu 159
Pertanyaan
How does electron transport create a proton gradient?
Jawaban
Released electron energy pumps protons from the matrix to the intermembrane space.
Kartu 160
Pertanyaan
What do NADH and FADH₂ carry?
Jawaban
High-energy electrons and associated hydrogen used in energy-transfer pathways.
Kartu 161
Pertanyaan
What is allosteric regulation?
Jawaban
A regulator binds at one site and changes activity at another site on the protein.
Kartu 162
Pertanyaan
What does carbon fixation accomplish?
Jawaban
It incorporates inorganic carbon dioxide into an organic molecule.
Kartu 163
Pertanyaan
What is oxidative phosphorylation?
Jawaban
ATP production powered by electron transport and chemiosmosis.
Kartu 164
Pertanyaan
Why use multiple biological replicates in a rate experiment?
Jawaban
They reveal natural variation and make the estimated treatment effect more reliable.
Kartu 165
Pertanyaan
What is fermentation's central purpose?
Jawaban
It regenerates NAD⁺ so glycolysis can continue without an active electron transport chain.
Kartu 166
Pertanyaan
How does feedback inhibition control a pathway?
Jawaban
A pathway's end product inhibits an earlier enzyme, reducing unnecessary production.
Kartu 167
Pertanyaan
What enzyme fixes carbon in the Calvin cycle?
Jawaban
Rubisco.
Kartu 168
Pertanyaan
How does mitochondrial ATP synthase make ATP?
Jawaban
Protons flow into the matrix through ATP synthase, driving ADP phosphorylation.
Kartu 169
Pertanyaan
Why do cells use stepwise electron transfers?
Jawaban
They release energy in manageable increments that can be captured instead of lost mostly as heat.
Kartu 170
Pertanyaan
What is a cofactor?
Jawaban
A nonprotein helper, often a metal ion or small organic coenzyme, required for some enzymes to function.
Kartu 171
Pertanyaan
What are the three broad phases of the Calvin cycle?
Jawaban
Carbon fixation, reduction, and regeneration of the carbon-dioxide acceptor RuBP.
Kartu 172
Pertanyaan
How does lactic-acid fermentation regenerate NAD⁺?
Jawaban
NADH reduces pyruvate to lactate, returning electrons to form NAD⁺.
Kartu 173
Pertanyaan
What is substrate-level phosphorylation?
Jawaban
An enzyme transfers a phosphate directly from an intermediate to ADP.
Kartu 174
Pertanyaan
Error bars overlap broadly between two treatments. What is a careful conclusion?
Jawaban
The graph alone does not show a clear difference; a suitable statistical analysis and design context are still needed.
Kartu 175
Pertanyaan
Why run an enzyme assay without enzyme?
Jawaban
It measures the uncatalyzed background change and tests whether enzyme is required.
Kartu 176
Pertanyaan
How does alcoholic fermentation regenerate NAD⁺?
Jawaban
Pyruvate loses carbon dioxide, and the remaining compound is reduced to ethanol as NADH becomes NAD⁺.
Kartu 177
Pertanyaan
What is G3P's role in photosynthesis?
Jawaban
It is a three-carbon product that can leave the Calvin cycle and help build carbohydrates.
Kartu 178
Pertanyaan
Why are mitochondrial cristae useful?
Jawaban
They increase inner-membrane area for electron transport chains and ATP synthase.
Kartu 179
Pertanyaan
What does phosphorylation often do to a molecule?
Jawaban
It adds a phosphate group that can increase reactivity or alter a protein's shape and activity.
Kartu 180
Pertanyaan
A mutation lowers an enzyme's maximum rate but not substrate binding. What is a plausible effect?
Jawaban
It may impair a catalytic step or reduce the number of functional enzyme molecules.
Kartu 181
Pertanyaan
Why must the Calvin cycle regenerate RuBP?
Jawaban
RuBP is the carbon-dioxide acceptor needed for another turn of fixation.
Kartu 182
Pertanyaan
A chemical lowers oxygen use but not glycolysis. Which stage is most directly implicated?
Jawaban
Aerobic electron transport or a process supplying it, because glycolysis itself does not consume oxygen.
Kartu 183
Pertanyaan
How would closed stomata affect photosynthesis?
Jawaban
Carbon dioxide entry falls, which can limit carbon fixation even when light is available.
Kartu 184
Pertanyaan
A plant receives green light only. Predict its photosynthetic rate.
Jawaban
It will usually be lower than under equally intense red or blue light because common chlorophylls absorb green poorly.
Kartu 185
Pertanyaan
Why does fermentation yield less ATP per glucose than aerobic respiration?
Jawaban
It relies on glycolysis alone and leaves much of glucose's chemical energy in reduced end products.
Kartu 186
Pertanyaan
How does low ATP affect respiration pathway activity?
Jawaban
It usually relieves inhibition of key enzymes, increasing fuel oxidation and ATP production.
Kartu 187
Pertanyaan
How can oxygen production estimate photosynthetic rate?
Jawaban
Oxygen is a light-reaction product, so its production per unit time can serve as a rate proxy under controlled conditions.
Kartu 188
Pertanyaan
What happens to electron transport if oxygen is removed?
Jawaban
The chain backs up because electrons lack a final acceptor; NADH accumulates and oxidative phosphorylation stops.
Kartu 189
Pertanyaan
Why does a light-response curve eventually level off?
Jawaban
Another factor, such as carbon dioxide supply, temperature, or enzyme capacity, becomes limiting.
Kartu 190
Pertanyaan
An uncoupler lets protons cross the inner mitochondrial membrane. What happens?
Jawaban
The gradient weakens, ATP production falls, and more energy is released as heat even if electron transport continues.
Kartu 191
Pertanyaan
What is direct-contact signaling?
Jawaban
A membrane-bound molecule or cell junction communicates with an adjacent cell.
Kartu 192
Pertanyaan
What are the three broad stages of cell signaling?
Jawaban
Reception, transduction, and response.
Kartu 193
Pertanyaan
How can a receptor mutation block a response even when ligand is present?
Jawaban
The receptor may fail to bind ligand, change shape, or activate the first relay protein.
Kartu 194
Pertanyaan
What is negative feedback?
Jawaban
A response reduces the original stimulus, helping stabilize a variable near a functional range.
Kartu 195
Pertanyaan
What happens during G1 phase?
Jawaban
The cell grows, performs normal functions, and prepares for DNA replication.
Kartu 196
Pertanyaan
Cells show response values of 2, 7, and 18 after rising ligand doses. Describe the trend.
Jawaban
The response increases with ligand dose across the tested range.
Kartu 197
Pertanyaan
What happens during reception?
Jawaban
A ligand binds its receptor and changes the receptor's activity or shape.
Kartu 198
Pertanyaan
What is paracrine signaling?
Jawaban
A cell releases a local regulator that acts on nearby target cells.
Kartu 199
Pertanyaan
What happens during S phase?
Jawaban
DNA is replicated, producing sister chromatids for each chromosome.
Kartu 200
Pertanyaan
A response occurs without ligand. What pathway defect is plausible?
Jawaban
A receptor or downstream relay protein may be constitutively active.
Kartu 201
Pertanyaan
What happens during signal transduction?
Jawaban
Intracellular steps relay and often amplify information from the activated receptor.
Kartu 202
Pertanyaan
What is synaptic signaling?
Jawaban
A neuron releases neurotransmitter across a short synaptic gap to a target cell.
Kartu 203
Pertanyaan
What happens during G2 phase?
Jawaban
The cell grows, checks replicated DNA, and prepares the machinery for division.
Kartu 204
Pertanyaan
Why compare receptor-positive and receptor-negative cells?
Jawaban
The comparison tests whether the receptor is necessary for the observed response.
Kartu 205
Pertanyaan
What counts as a cellular response?
Jawaban
A change in gene expression, enzyme activity, ion flow, secretion, movement, division, or another cell behavior.
Kartu 206
Pertanyaan
How does insulin participate in negative feedback?
Jawaban
High blood glucose promotes insulin release, which lowers blood glucose and reduces the original stimulus.
Kartu 207
Pertanyaan
What happens during mitosis?
Jawaban
A eukaryotic nucleus separates duplicated chromosomes into two nuclei.
Kartu 208
Pertanyaan
What is endocrine signaling?
Jawaban
Hormones travel through circulatory fluid to target cells that may be far away.
Kartu 209
Pertanyaan
What does a protein kinase do?
Jawaban
It transfers a phosphate from ATP to a target protein.
Kartu 210
Pertanyaan
A drug blocks a kinase, and the final response disappears. What is supported?
Jawaban
The kinase is required somewhere in that pathway under the tested conditions.
Kartu 211
Pertanyaan
What happens during cytokinesis?
Jawaban
The cytoplasm divides to form separate daughter cells.
Kartu 212
Pertanyaan
How does glucagon participate in glucose homeostasis?
Jawaban
Low blood glucose promotes glucagon release, which raises blood glucose toward the normal range.
Kartu 213
Pertanyaan
What does a protein phosphatase do?
Jawaban
It removes a phosphate group from a target protein.
Kartu 214
Pertanyaan
What is a ligand?
Jawaban
A signaling molecule that binds specifically to a receptor.
Kartu 215
Pertanyaan
What is the G1 checkpoint's broad role?
Jawaban
It checks size, nutrients, growth signals, and DNA condition before replication.
Kartu 216
Pertanyaan
Why can't one inhibitor experiment prove a protein's exact pathway position?
Jawaban
Off-target effects and indirect dependencies can produce the same outcome.
Kartu 217
Pertanyaan
Why are phosphorylation cascades reversible?
Jawaban
Kinases add phosphates, while phosphatases remove them and reset pathway components.
Kartu 218
Pertanyaan
What is positive feedback?
Jawaban
A response strengthens the initiating stimulus until a separate event stops the loop.
Kartu 219
Pertanyaan
What is the G2 checkpoint's broad role?
Jawaban
It checks whether DNA replication is complete and damage is repaired before mitosis.
Kartu 220
Pertanyaan
Why don't all cells respond to the same hormone?
Jawaban
Only cells with a compatible receptor and response machinery can respond.
Kartu 221
Pertanyaan
What is a second messenger?
Jawaban
A small intracellular molecule or ion that relays a signal after receptor activation.
Kartu 222
Pertanyaan
How can rescue with an active downstream protein map a pathway?
Jawaban
If the response returns despite an upstream block, the rescued protein likely acts downstream of that block.
Kartu 223
Pertanyaan
What does the spindle checkpoint verify?
Jawaban
Every chromosome is correctly attached to spindle microtubules before sister chromatids separate.
Kartu 224
Pertanyaan
Why is blood clotting a positive-feedback process?
Jawaban
Activated platelets recruit and activate more platelets until the break is sealed.
Kartu 225
Pertanyaan
Name two common second messengers.
Jawaban
Cyclic AMP and calcium ions.
Kartu 226
Pertanyaan
A mutant receptor binds ligand but never becomes phosphorylated. Predict downstream signaling.
Jawaban
It will likely fall or disappear if receptor phosphorylation is required to recruit relay proteins.
Kartu 227
Pertanyaan
How do cyclins regulate the cell cycle?
Jawaban
Their concentrations rise and fall, activating cyclin-dependent kinases at specific stages.
Kartu 228
Pertanyaan
Why must DNA replicate before mitosis?
Jawaban
Each daughter nucleus needs a complete copy of the genome.
Kartu 229
Pertanyaan
Where do receptors for many peptide hormones sit?
Jawaban
In the plasma membrane, because these polar ligands do not readily cross the lipid bilayer.
Kartu 230
Pertanyaan
How can a signaling pathway amplify a weak signal?
Jawaban
One activated component activates many downstream molecules at successive steps.
Kartu 231
Pertanyaan
What is the dependent variable in a ligand-dose experiment?
Jawaban
The measured response, such as reporter activity, enzyme phosphorylation, or ion concentration.
Kartu 232
Pertanyaan
What do cyclin-dependent kinases do?
Jawaban
When paired with cyclins, they phosphorylate targets that drive cell-cycle transitions.
Kartu 233
Pertanyaan
Why doesn't positive feedback usually maintain homeostasis by itself?
Jawaban
It drives change away from the starting state and needs an external stop.
Kartu 234
Pertanyaan
What is a G protein's signaling role?
Jawaban
It switches activity when bound to GTP and relays information from certain membrane receptors to effectors.
Kartu 235
Pertanyaan
How would you test whether calcium is required for a response?
Jawaban
Block the calcium rise while keeping other conditions matched, then compare the response with a vehicle control.
Kartu 236
Pertanyaan
What is apoptosis?
Jawaban
Programmed cell death that dismantles a cell in a controlled way.
Kartu 237
Pertanyaan
Where are receptors for many steroid hormones?
Jawaban
Inside the cell, where lipid-soluble hormones can bind after crossing the membrane.
Kartu 238
Pertanyaan
How can an ion-channel receptor create a rapid response?
Jawaban
Ligand binding opens or closes a pore, quickly changing ion movement and membrane conditions.
Kartu 239
Pertanyaan
Why test several ligand concentrations?
Jawaban
A dose–response series can reveal sensitivity, saturation, and whether effects scale with ligand.
Kartu 240
Pertanyaan
Why is apoptosis useful in multicellular organisms?
Jawaban
It removes damaged, infected, or unneeded cells with limited harm to neighbors.
Kartu 241
Pertanyaan
A thermostat-like pathway overshoots repeatedly. What defect is plausible?
Jawaban
Delayed sensing or response can make negative feedback correct too late.
Kartu 242
Pertanyaan
How can an intracellular receptor affect gene expression?
Jawaban
The ligand–receptor complex can act directly or indirectly as a transcription regulator.
Kartu 243
Pertanyaan
Cells lacking protein X divide despite DNA damage. Justify a checkpoint claim.
Jawaban
Protein X likely supports a DNA-damage checkpoint because its absence links damage with continued division; rescue or pathway tests would strengthen the claim.
Kartu 244
Pertanyaan
What aligns at the metaphase plate?
Jawaban
Duplicated chromosomes attached to spindle microtubules from opposite poles.
Kartu 245
Pertanyaan
How can failed checkpoints contribute to cancer?
Jawaban
Cells with damage or abnormal signals can keep dividing instead of pausing or dying.
Kartu 246
Pertanyaan
How can gap junctions support communication?
Jawaban
They connect neighboring animal-cell cytoplasms so small molecules and ions can pass directly.
Kartu 247
Pertanyaan
Why can the same ligand trigger different responses in two cell types?
Jawaban
The cells can express different receptors, relay proteins, targets, or genes.
Kartu 248
Pertanyaan
Two pathways share one relay protein. What can happen if that protein is blocked?
Jawaban
Both responses may weaken, showing pathway crosstalk or a shared component.
Kartu 249
Pertanyaan
During which mitotic stage do sister chromatids separate?
Jawaban
Anaphase.
Kartu 250
Pertanyaan
What defines a malignant tumor?
Jawaban
Its cells invade surrounding tissue and may spread to distant sites.
Kartu 251
Pertanyaan
How would loss of a feedback inhibitor affect a biosynthetic pathway?
Jawaban
The pathway may stay active and overproduce its end product.
Kartu 252
Pertanyaan
What ends a signaling response?
Jawaban
Ligand removal, receptor inactivation, GTP hydrolysis, messenger breakdown, or dephosphorylation can shut it down.
Kartu 253
Pertanyaan
A pathway diagram shows A activates B, and B inhibits C. Predict C after A activation.
Jawaban
C activity should decrease, assuming the shown links are the relevant controlling interactions.
Kartu 254
Pertanyaan
A phosphatase that normally turns off an activated relay protein is inhibited. Predict the effect on that pathway.
Jawaban
Phosphorylated targets may stay active longer, extending or strengthening the response.
Kartu 255
Pertanyaan
A drug prevents spindle formation. Where should the cycle stop?
Jawaban
At the spindle checkpoint before anaphase, because chromosomes cannot attach correctly.
Kartu 256
Pertanyaan
What is the purpose of meiosis?
Jawaban
It produces haploid cells and reshuffles inherited alleles for sexual reproduction.
Kartu 257
Pertanyaan
What is crossing over?
Jawaban
Exchange of corresponding DNA segments between nonsister chromatids of homologous chromosomes.
Kartu 258
Pertanyaan
What does Mendel's law of segregation describe?
Jawaban
An individual's two alleles for a gene separate into different gametes.
Kartu 259
Pertanyaan
Why do X-linked recessive traits often appear more frequently in XY individuals?
Jawaban
They have only one X chromosome, so one recessive allele on it can determine the phenotype.
Kartu 260
Pertanyaan
What is incomplete dominance?
Jawaban
The heterozygote has a phenotype intermediate between the two homozygotes.
Kartu 261
Pertanyaan
What does a chi-square goodness-of-fit test compare?
Jawaban
Observed category counts with counts expected under a stated model.
Kartu 262
Pertanyaan
What is a homologous chromosome pair?
Jawaban
Two chromosomes carrying the same gene locations, one inherited from each parent, possibly with different alleles.
Kartu 263
Pertanyaan
What does Mendel's law of independent assortment describe?
Jawaban
Alleles of genes on different chromosomes, or far apart on one chromosome, assort independently during gamete formation.
Kartu 264
Pertanyaan
What is genetic linkage?
Jawaban
Genes close together on the same chromosome tend to be inherited together.
Kartu 265
Pertanyaan
When does crossing over occur?
Jawaban
During prophase I after homologs pair.
Kartu 266
Pertanyaan
How do sister chromatids differ from homologous chromosomes?
Jawaban
Sister chromatids are replicated copies of one chromosome; homologs are the maternal and paternal versions of the same chromosome type.
Kartu 267
Pertanyaan
For Aa × Aa, what is the expected genotype ratio?
Jawaban
1 AA : 2 Aa : 1 aa.
Kartu 268
Pertanyaan
How can linked genes produce recombinant offspring?
Jawaban
Crossing over can exchange DNA between the gene locations.
Kartu 269
Pertanyaan
What is the usual null hypothesis for a Mendelian chi-square test?
Jawaban
Any difference between observed and expected counts is due to chance sampling under the proposed inheritance model.
Kartu 270
Pertanyaan
What happens to homologous chromosomes in meiosis I?
Jawaban
They pair and then separate into different cells.
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Kartu 271
Pertanyaan
For Aa × Aa with complete dominance, what is the expected phenotype ratio?
Jawaban
3 dominant phenotype : 1 recessive phenotype.
Kartu 272
Pertanyaan
How does crossing over increase variation?
Jawaban
It creates chromosomes with new combinations of parental alleles.
Kartu 273
Pertanyaan
What does recombination frequency estimate?
Jawaban
Relative distance between linked genes; higher frequency generally means greater separation, up to the 50% limit.
Kartu 274
Pertanyaan
What happens to sister chromatids in meiosis II?
Jawaban
Their centromeres separate, and the chromatids move into different cells.
Kartu 275
Pertanyaan
What rule finds the probability of either of two mutually exclusive outcomes?
Jawaban
Add their individual probabilities.
Kartu 276
Pertanyaan
What is codominance?
Jawaban
Both alleles contribute distinct, detectable products or traits in the heterozygote.
Kartu 277
Pertanyaan
How is a chi-square contribution calculated for one category?
Jawaban
Subtract expected from observed, square the difference, and divide by expected.
Kartu 278
Pertanyaan
When do homologous chromosomes pair as tetrads?
Jawaban
During prophase I.
Kartu 279
Pertanyaan
What rule finds the probability that independent events both occur?
Jawaban
Multiply their individual probabilities.
Kartu 280
Pertanyaan
What is independent assortment?
Jawaban
Each homologous pair orients independently at metaphase I, producing many maternal–paternal chromosome combinations.
Kartu 281
Pertanyaan
Why can't recombination frequency exceed 50%?
Jawaban
At 50%, recombinant and parental combinations are equally common and the genes behave as if unlinked.
Kartu 282
Pertanyaan
What aligns at the metaphase I plate?
Jawaban
Homologous pairs, with each homolog attached toward an opposite pole.
Kartu 283
Pertanyaan
What is a test cross?
Jawaban
Crossing an individual with a dominant phenotype to a homozygous recessive individual to infer the unknown genotype.
Kartu 284
Pertanyaan
How can one gene have multiple alleles?
Jawaban
More than two allele forms can exist in the population, although one diploid individual carries at most two.
Kartu 285
Pertanyaan
How are total chi-square and category contributions related?
Jawaban
Total chi-square is the sum of all category contributions.
Kartu 286
Pertanyaan
What separates during anaphase I?
Jawaban
Homologous chromosomes; sister chromatids remain joined.
Kartu 287
Pertanyaan
How does random fertilization increase variation?
Jawaban
Any one genetically varied gamete from one parent can fuse with any compatible gamete from the other.
Kartu 288
Pertanyaan
A test cross yields about half recessive offspring. What genotype is supported for the unknown parent?
Jawaban
Heterozygous.
Kartu 289
Pertanyaan
What is nondisjunction?
Jawaban
Failure of homologous chromosomes or sister chromatids to separate normally.
Kartu 290
Pertanyaan
What aligns during metaphase II?
Jawaban
Individual duplicated chromosomes in each haploid cell.
Kartu 291
Pertanyaan
What is polygenic inheritance?
Jawaban
Multiple genes contribute to one trait, often producing continuous phenotypic variation.
Kartu 292
Pertanyaan
For a simple goodness-of-fit test, how are degrees of freedom found?
Jawaban
Number of categories minus one.
Kartu 293
Pertanyaan
Which meiotic events create variation before fertilization?
Jawaban
Crossing over and independent assortment.
Kartu 294
Pertanyaan
How does ploidy change during meiosis?
Jawaban
Homolog separation reduces diploid cells to haploid cells; meiosis II separates chromatids without another ploidy reduction.
Kartu 295
Pertanyaan
What pedigree pattern often suggests a recessive trait?
Jawaban
Unaffected parents can have an affected child, if both parents carry the allele.
Kartu 296
Pertanyaan
How can meiotic nondisjunction affect gametes?
Jawaban
It can produce gametes with an extra or missing chromosome.
Kartu 297
Pertanyaan
What is pleiotropy?
Jawaban
One gene influences multiple phenotypic traits.
Kartu 298
Pertanyaan
Why is there no second DNA replication before meiosis II?
Jawaban
The goal is to separate existing sister chromatids, not duplicate the genome again.
Kartu 299
Pertanyaan
What does a p-value below the chosen threshold support?
Jawaban
Rejecting the null model because the observed deviation would be unlikely if that model were correct.
Kartu 300
Pertanyaan
Why are siblings genetically different even with the same parents?
Jawaban
They inherit different allele combinations through crossing over, independent assortment, and random fertilization.
Kartu 301
Pertanyaan
Why do small families often deviate from expected Mendelian ratios?
Jawaban
Probability ratios describe long-run expectations; random sampling variation is large with few offspring.
Kartu 302
Pertanyaan
A diploid cell has six chromosomes. How many chromosomes should each normal meiotic product have?
Jawaban
Three.
Kartu 303
Pertanyaan
A trisomic zygote forms after fertilization. What meiotic error is a likely cause?
Jawaban
Nondisjunction produced a gamete carrying an extra copy of that chromosome.
Kartu 304
Pertanyaan
Why can identical genotypes show different phenotypes?
Jawaban
Environmental conditions and developmental variation can alter gene expression or trait development.
Kartu 305
Pertanyaan
What does failing to reject a genetic null hypothesis mean?
Jawaban
The data do not show a significant departure from the model; they do not prove the model true.
Kartu 306
Pertanyaan
How do DNA and RNA sugars differ?
Jawaban
DNA contains deoxyribose; RNA contains ribose.
Kartu 307
Pertanyaan
What does semiconservative DNA replication produce?
Jawaban
Each daughter DNA molecule contains one original strand and one newly synthesized strand.
Kartu 308
Pertanyaan
What is transcription?
Jawaban
Synthesis of RNA using DNA as a template.
Kartu 309
Pertanyaan
What is a point mutation?
Jawaban
A change affecting one nucleotide pair.
Kartu 310
Pertanyaan
What is an operon?
Jawaban
A group of prokaryotic genes controlled together and transcribed from one promoter.
Kartu 311
Pertanyaan
Why can muscle and nerve cells differ despite having the same genome?
Jawaban
They express different sets and amounts of genes.
Kartu 312
Pertanyaan
What must a virus use from its host?
Jawaban
Host resources and at least some host-cell machinery to copy or express its genome and produce new particles.
Kartu 313
Pertanyaan
What does PCR do?
Jawaban
It amplifies a chosen DNA region through repeated cycles of strand separation, primer binding, and extension.
Kartu 314
Pertanyaan
What enzyme performs transcription?
Jawaban
RNA polymerase.
Kartu 315
Pertanyaan
What does helicase do during replication?
Jawaban
It unwinds the double helix and separates the template strands.
Kartu 316
Pertanyaan
How does a repressor reduce transcription?
Jawaban
It binds regulatory DNA and blocks or hinders transcription machinery.
Kartu 317
Pertanyaan
What is a silent mutation?
Jawaban
A nucleotide change that does not change the encoded amino acid.
Kartu 318
Pertanyaan
What does a promoter do?
Jawaban
It marks where transcription machinery assembles and helps set the transcription start and direction.
Kartu 319
Pertanyaan
What does topoisomerase do ahead of a replication fork?
Jawaban
It relieves twisting strain caused by DNA unwinding.
Kartu 320
Pertanyaan
How does an inducer affect an inducible operon?
Jawaban
It disables the repressor or otherwise turns transcription on when the pathway's substrate is present.
Kartu 321
Pertanyaan
How do DNA and RNA bases differ?
Jawaban
DNA uses thymine, while RNA uses uracil; both also use adenine, cytosine, and guanine.
Kartu 322
Pertanyaan
Which DNA strand does RNA polymerase read?
Jawaban
The template strand, read 3′→5′ while RNA is built 5′→3′.
Kartu 323
Pertanyaan
Why is an RNA primer needed for DNA replication?
Jawaban
DNA polymerase can extend an existing 3′ end but cannot start a strand from nothing.
Kartu 324
Pertanyaan
How does a corepressor affect a repressible operon?
Jawaban
It activates a repressor, turning off genes when the pathway's end product is abundant.
Kartu 325
Pertanyaan
What is a missense mutation?
Jawaban
A nucleotide change that substitutes one amino acid for another.
Kartu 326
Pertanyaan
How does an mRNA sequence relate to the coding DNA strand?
Jawaban
It matches the coding strand except RNA has uracil in place of thymine.
Kartu 327
Pertanyaan
What does primase do?
Jawaban
It builds short RNA primers.
Kartu 328
Pertanyaan
Why is the lac operon strongly expressed when lactose is present and glucose is scarce?
Jawaban
Lactose relieves repression, while low glucose supports positive activation of transcription.
Kartu 329
Pertanyaan
Why are primers essential in PCR?
Jawaban
They define the target boundaries and provide 3′ ends for DNA polymerase.
Kartu 330
Pertanyaan
What is the primary RNA transcript in a eukaryote?
Jawaban
The initial RNA copy before processing.
Kartu 331
Pertanyaan
In which direction does DNA polymerase synthesize DNA?
Jawaban
5′→3′ by adding nucleotides to a 3′ end.
Kartu 332
Pertanyaan
Why is the trp operon usually off when tryptophan is abundant?
Jawaban
Tryptophan acts as a corepressor, enabling repression of biosynthetic genes.
Kartu 333
Pertanyaan
What holds complementary DNA bases together?
Jawaban
Hydrogen bonds: adenine pairs with thymine, and cytosine pairs with guanine.
Kartu 334
Pertanyaan
What happens during RNA splicing?
Jawaban
Introns are removed and exons are joined.
Kartu 335
Pertanyaan
Why is the leading strand synthesized continuously?
Jawaban
Its template orientation lets polymerase follow the replication fork while synthesizing 5′→3′.
Kartu 336
Pertanyaan
How can histone acetylation affect transcription?
Jawaban
It often loosens chromatin and makes DNA more accessible to transcription machinery.
Kartu 337
Pertanyaan
What is a nonsense mutation?
Jawaban
A nucleotide change that creates a premature stop codon.
Kartu 338
Pertanyaan
What do the 5′ cap and poly-A tail help do?
Jawaban
They protect eukaryotic mRNA and support export and translation.
Kartu 339
Pertanyaan
Why is the lagging strand synthesized in fragments?
Jawaban
Its template orientation forces repeated 5′→3′ synthesis away from the moving fork.
Kartu 340
Pertanyaan
How can DNA methylation near a promoter affect transcription?
Jawaban
It often reduces transcription by limiting access or recruiting repressive proteins.
Kartu 341
Pertanyaan
How does gel electrophoresis separate DNA fragments?
Jawaban
An electric field pulls negatively charged DNA through a matrix; smaller fragments usually travel farther.
Kartu 342
Pertanyaan
How can alternative splicing increase protein diversity?
Jawaban
Different exon combinations from one transcript can produce different mRNAs and polypeptides.
Kartu 343
Pertanyaan
What are Okazaki fragments?
Jawaban
Short DNA segments made on the lagging strand.
Kartu 344
Pertanyaan
What does a transcription factor do?
Jawaban
It binds regulatory DNA and helps increase or decrease transcription of specific genes.
Kartu 345
Pertanyaan
Why are DNA strands antiparallel?
Jawaban
Their sugar–phosphate backbones run in opposite 5′→3′ directions.
Kartu 346
Pertanyaan
What is translation?
Jawaban
Ribosomes use an mRNA codon sequence to build a polypeptide.
Kartu 347
Pertanyaan
What does DNA ligase do?
Jawaban
It seals breaks in the sugar–phosphate backbone, joining DNA fragments.
Kartu 348
Pertanyaan
What is a frameshift mutation?
Jawaban
An insertion or deletion not in multiples of three that shifts downstream codon grouping.
Kartu 349
Pertanyaan
How can an enhancer influence a distant promoter?
Jawaban
DNA looping brings enhancer-bound activators near the transcription machinery.
Kartu 350
Pertanyaan
What does a codon specify?
Jawaban
An amino acid or a translation stop signal.
Kartu 351
Pertanyaan
What do restriction enzymes do?
Jawaban
They cut DNA at particular recognition sequences.
Kartu 352
Pertanyaan
What gives a nucleic-acid strand its 5′ and 3′ ends?
Jawaban
The chemical groups on the sugar: a 5′ phosphate end and a 3′ hydroxyl end.
Kartu 353
Pertanyaan
How does proofreading improve replication accuracy?
Jawaban
DNA polymerases detect and replace many incorrectly paired nucleotides.
Kartu 354
Pertanyaan
What does a tRNA anticodon do?
Jawaban
It base-pairs with an mRNA codon so the attached amino acid is placed correctly.
Kartu 355
Pertanyaan
Why can a promoter mutation affect protein amount?
Jawaban
It can change transcription-factor or RNA-polymerase binding and alter transcription rate.
Kartu 356
Pertanyaan
How can microRNA reduce gene expression?
Jawaban
It base-pairs with target mRNA and promotes degradation or blocks translation.
Kartu 357
Pertanyaan
What maintains a differentiated cell's identity?
Jawaban
Stable regulatory networks and chromatin states keep characteristic genes active or silent.
Kartu 358
Pertanyaan
What are the ribosome's broad roles?
Jawaban
It positions mRNA and tRNAs and catalyzes peptide-bond formation.
Kartu 359
Pertanyaan
How can an RNA virus generate genetic variation quickly?
Jawaban
Many viral RNA polymerases lack strong proofreading, so replication introduces mutations frequently.
Kartu 360
Pertanyaan
What can bacterial transformation demonstrate?
Jawaban
Cells can take up external DNA and express a selectable or observable trait.
Kartu 361
Pertanyaan
Why is RNA usually more structurally varied than double-stranded DNA?
Jawaban
A single RNA strand can fold back on itself through internal base pairing.
Kartu 362
Pertanyaan
What usually marks translation initiation?
Jawaban
A start codon positioned with an initiator tRNA and ribosomal subunits.
Kartu 363
Pertanyaan
What problem do telomeres help solve?
Jawaban
They protect chromosome ends from losing essential genes during repeated linear-DNA replication.
Kartu 364
Pertanyaan
Why can an intron splice-site mutation affect protein sequence?
Jawaban
Incorrect splicing can remove exon sequence or retain intron sequence in the mature mRNA.
Kartu 365
Pertanyaan
How can protein degradation regulate a pathway quickly?
Jawaban
Destroying a key protein lowers its activity without waiting for transcription to change.
Kartu 366
Pertanyaan
What happens at a stop codon?
Jawaban
A release factor ends translation and frees the polypeptide.
Kartu 367
Pertanyaan
How can a signal change cell specialization?
Jawaban
It can activate transcription factors that launch a new gene-expression program.
Kartu 368
Pertanyaan
What is a retrovirus's information flow?
Jawaban
Viral RNA is reverse-transcribed into DNA, which can integrate into the host genome.
Kartu 369
Pertanyaan
What does DNA sequencing reveal directly?
Jawaban
The order of nucleotides in the analyzed DNA; biological effects require further interpretation.
Kartu 370
Pertanyaan
Why is the genetic code called redundant?
Jawaban
More than one codon can specify the same amino acid.
Kartu 371
Pertanyaan
Where does nucleotide sequence store information?
Jawaban
The order of bases encodes information that can be copied, transcribed, or translated.
Kartu 372
Pertanyaan
Why is replication called bidirectional?
Jawaban
Two forks usually move away from each origin in opposite directions.
Kartu 373
Pertanyaan
Why doesn't every DNA mutation change phenotype?
Jawaban
It may occur outside a functional sequence, be silent, have a mild effect, or be masked by another allele or environment.
Kartu 374
Pertanyaan
How does a free ribosome's product usually differ from a rough-ER ribosome's product?
Jawaban
Free ribosomes often make cytosolic proteins; ER-bound ribosomes make many secreted, membrane, and endomembrane proteins.
Kartu 375
Pertanyaan
Why can one signal coordinate many genes?
Jawaban
A shared transcription regulator or signaling pathway can control multiple target promoters.
Kartu 376
Pertanyaan
Why does cell specialization depend on selective gene expression rather than gene loss?
Jawaban
Most specialized cells retain the genome but use only the genes needed for their role.
Kartu 377
Pertanyaan
Why are viruses not described as independently living cells?
Jawaban
They lack cellular metabolism and cannot reproduce without a host cell.
Kartu 378
Pertanyaan
A coding DNA triplet is 5′-ATG-3′. What is the matching mRNA codon?
Jawaban
5′-AUG-3′.
Kartu 379
Pertanyaan
A PCR band is absent. Why isn't gene absence the only explanation?
Jawaban
Poor DNA quality, wrong primers, inhibitors, or failed reaction conditions can also prevent amplification.
Kartu 380
Pertanyaan
Why can protein function require steps after translation?
Jawaban
The polypeptide may need folding, cleavage, chemical modification, or assembly with other subunits.
Kartu 381
Pertanyaan
How do fossils support evolution?
Jawaban
They document organisms and transitions through time, including appearance, change, and extinction.
Kartu 382
Pertanyaan
What conditions are required for natural selection?
Jawaban
Individuals vary, some variation is heritable, and variants differ in survival or reproductive success in that environment.
Kartu 383
Pertanyaan
What is artificial selection?
Jawaban
Humans choose which organisms reproduce based on desired heritable traits.
Kartu 384
Pertanyaan
What does an allele frequency measure?
Jawaban
The fraction of all copies of a gene in a population represented by one allele.
Kartu 385
Pertanyaan
What does a node on a phylogenetic tree represent?
Jawaban
A common ancestor where descendant lineages diverge.
Kartu 386
Pertanyaan
What is biological speciation?
Jawaban
Evolution of reproductive isolation between populations, producing independently evolving lineages.
Kartu 387
Pertanyaan
What is extinction?
Jawaban
Permanent loss of a species when no living members remain.
Kartu 388
Pertanyaan
A pesticide-treated population becomes mostly resistant. What evidence distinguishes selection from acclimation?
Jawaban
Resistance should be heritable and increase across generations through differential reproduction, not just appear temporarily in exposed individuals.
Kartu 389
Pertanyaan
What changes during evolution by natural selection?
Jawaban
Allele frequencies in a population across generations.
Kartu 390
Pertanyaan
For two alleles under Hardy–Weinberg notation, what does p + q equal?
Jawaban
1.
Kartu 391
Pertanyaan
What is a clade?
Jawaban
An ancestor and all of its descendants.
Kartu 392
Pertanyaan
What does homologous anatomy suggest?
Jawaban
Similar underlying structures with different functions can indicate inheritance from a common ancestor.
Kartu 393
Pertanyaan
Do individual organisms evolve by natural selection?
Jawaban
No. Individuals are selected; populations evolve as inherited variants change in frequency.
Kartu 394
Pertanyaan
Under Hardy–Weinberg equilibrium, what does p² represent?
Jawaban
Expected frequency of one homozygous genotype.
Kartu 395
Pertanyaan
What is a shared derived character?
Jawaban
A trait that evolved in a common ancestor and helps identify one of its descendant clades.
Kartu 396
Pertanyaan
What is mutation's evolutionary role?
Jawaban
It creates new alleles, the ultimate source of new genetic variation.
Kartu 397
Pertanyaan
What is biological fitness?
Jawaban
Relative contribution of viable, reproducing offspring to the next generation in a particular environment.
Kartu 398
Pertanyaan
Under Hardy–Weinberg equilibrium, what does 2pq represent?
Jawaban
Expected frequency of heterozygotes.
Kartu 399
Pertanyaan
Which two tips on a tree are most closely related?
Jawaban
Those sharing the most recent common ancestor, regardless of how close their names appear on the page.
Kartu 400
Pertanyaan
What is a vestigial structure?
Jawaban
A reduced feature inherited from ancestors that has lost much or all of its earlier function.
Kartu 401
Pertanyaan
What is an adaptation?
Jawaban
A heritable trait that became common because it improved fitness in past environments.
Kartu 402
Pertanyaan
Under Hardy–Weinberg equilibrium, what does q² represent?
Jawaban
Expected frequency of the other homozygous genotype.
Kartu 403
Pertanyaan
How does recombination affect evolution?
Jawaban
It reshuffles existing alleles into new combinations but does not itself create new alleles.
Kartu 404
Pertanyaan
Does rotating branches around a node change relationships?
Jawaban
No. The branching pattern stays the same.
Kartu 405
Pertanyaan
Why isn't an adaptation always beneficial in every setting?
Jawaban
Fitness effects depend on the environment and can involve tradeoffs.
Kartu 406
Pertanyaan
What are the Hardy–Weinberg assumptions?
Jawaban
A very large population, random mating, no mutation, no migration, and no natural selection at the locus.
Kartu 407
Pertanyaan
How can embryological similarities support common ancestry?
Jawaban
Shared developmental patterns can reflect inherited developmental genes and pathways.
Kartu 408
Pertanyaan
What is gene flow?
Jawaban
Movement of alleles between populations through migration and reproduction.
Kartu 409
Pertanyaan
Does natural selection create needed mutations?
Jawaban
No. Mutations arise without regard to need; selection changes the frequencies of their inherited effects.
Kartu 410
Pertanyaan
Why is Hardy–Weinberg equilibrium useful?
Jawaban
It provides a null model for detecting or reasoning about evolutionary change.
Kartu 411
Pertanyaan
Does left-to-right tip order show evolutionary progress?
Jawaban
No. Tip order is a drawing choice, not a ranking from primitive to advanced.
Kartu 412
Pertanyaan
What is allopatric speciation?
Jawaban
Geographic separation reduces gene flow, allowing populations to diverge.
Kartu 413
Pertanyaan
What is directional selection?
Jawaban
Selection favors one end of a phenotypic range, shifting the population mean.
Kartu 414
Pertanyaan
If q² = 0.09, what is q?
Jawaban
0.30.
Kartu 415
Pertanyaan
Why is DNA sequence similarity evidence for relatedness?
Jawaban
Related lineages inherit sequences from common ancestors, with differences accumulating over time.
Kartu 416
Pertanyaan
How does gene flow often affect differences between populations?
Jawaban
It tends to make allele frequencies more similar.
Kartu 417
Pertanyaan
What is stabilizing selection?
Jawaban
Selection favors intermediate phenotypes and removes extremes.
Kartu 418
Pertanyaan
If q = 0.30, what is p?
Jawaban
0.70.
Kartu 419
Pertanyaan
What can branch length mean?
Jawaban
Only what the figure defines—sometimes time or amount of change, and sometimes nothing quantitative.
Kartu 420
Pertanyaan
What is sympatric speciation?
Jawaban
Reproductive isolation evolves without geographic separation, for example through polyploidy or strong niche and mating differences.
Kartu 421
Pertanyaan
What is disruptive selection?
Jawaban
Selection favors both extremes over intermediate phenotypes.
Kartu 422
Pertanyaan
If p = 0.70 and q = 0.30, what is 2pq?
Jawaban
0.42.
Kartu 423
Pertanyaan
Why include an untreated population in a selection experiment?
Jawaban
It shows how allele or trait frequencies change without the selective treatment.
Kartu 424
Pertanyaan
Why is the nearly universal genetic code evidence of common ancestry?
Jawaban
A deeply conserved information system is most simply explained by inheritance from early shared ancestors.
Kartu 425
Pertanyaan
What is balancing selection?
Jawaban
Natural selection that maintains two or more alleles in a population, such as through heterozygote advantage or selection that varies across environments.
Kartu 426
Pertanyaan
What is genetic drift?
Jawaban
Random change in allele frequencies caused by chance sampling across generations.
Kartu 427
Pertanyaan
If 16% of a Hardy–Weinberg population shows a recessive phenotype, what is q?
Jawaban
0.40, because q is the square root of 0.16.
Kartu 428
Pertanyaan
Why use an outgroup in tree analysis?
Jawaban
It helps infer which character states are ancestral versus derived in the focal group.
Kartu 429
Pertanyaan
What is a prezygotic barrier?
Jawaban
A barrier that prevents mating or fertilization.
Kartu 430
Pertanyaan
Allele A rises from 0.20 to 0.45. Describe the evolutionary result.
Jawaban
The population evolved at that locus because allele frequency changed.
Kartu 431
Pertanyaan
How does biogeography support evolution?
Jawaban
Species distributions often match isolation history, dispersal, and descent from nearby ancestors.
Kartu 432
Pertanyaan
What is sexual selection?
Jawaban
Differences in mating success drive changes in traits that affect mate attraction or competition.
Kartu 433
Pertanyaan
When is genetic drift strongest?
Jawaban
In small populations.
Kartu 434
Pertanyaan
Why can a rare recessive allele persist?
Jawaban
Selection cannot remove copies hidden in heterozygotes as efficiently as copies expressed in homozygotes.
Kartu 435
Pertanyaan
How can molecular data revise a phylogenetic tree?
Jawaban
Sequence comparisons can reveal relationships not obvious from morphology or distinguish convergence from homology.
Kartu 436
Pertanyaan
What is a postzygotic barrier?
Jawaban
A barrier that reduces hybrid survival, fertility, or later-generation success after fertilization.
Kartu 437
Pertanyaan
How can rapid environmental change increase extinction risk?
Jawaban
Populations may lack enough suitable variation or time to adapt or move.
Kartu 438
Pertanyaan
A small island population loses alleles after a storm. Which mechanism is most direct?
Jawaban
Genetic drift through a bottleneck.
Kartu 439
Pertanyaan
What is convergent evolution?
Jawaban
Unrelated lineages independently evolve similar traits under similar selective pressures.
Kartu 440
Pertanyaan
Why can antibiotic resistance spread rapidly?
Jawaban
Treatment strongly favors resistant variants already present or newly introduced, which leave more descendants.
Kartu 441
Pertanyaan
What is a bottleneck effect?
Jawaban
A sharp population reduction leaves a random, often less diverse sample of the original gene pool.
Kartu 442
Pertanyaan
How do genotype counts yield allele frequency?
Jawaban
Count two copies from each homozygote and one from each heterozygote, then divide by twice the number of diploid individuals.
Kartu 443
Pertanyaan
What is maximum parsimony in tree building?
Jawaban
Preferring the tree that requires the fewest evolutionary changes under the model.
Kartu 444
Pertanyaan
How can different breeding times isolate populations?
Jawaban
Temporal isolation prevents individuals from mating even when they share a location.
Kartu 445
Pertanyaan
Why can mass extinctions reshape evolution?
Jawaban
They remove many lineages and open ecological opportunities for survivors.
Kartu 446
Pertanyaan
Two similar traits evolved on distant tree branches. What explanation should be evaluated?
Jawaban
Convergent evolution under similar selection, alongside the possibility of an incorrect tree or unrecognized homology.
Kartu 447
Pertanyaan
Why are analogous structures weak evidence of close ancestry?
Jawaban
Their similar function may have evolved independently rather than from the same ancestral structure.
Kartu 448
Pertanyaan
Why doesn't natural selection produce perfection?
Jawaban
It works with existing variation under tradeoffs, historical constraints, chance, and changing environments.
Kartu 449
Pertanyaan
What is a founder effect?
Jawaban
A new population starts from a small, nonrepresentative sample of a source population.
Kartu 450
Pertanyaan
Observed genotypes differ from Hardy–Weinberg expectations. What is supported?
Jawaban
At least one model assumption may not hold, or sampling error may matter; the deviation alone does not identify the cause.
Kartu 451
Pertanyaan
Why is a phylogenetic tree a hypothesis?
Jawaban
It is an evidence-based reconstruction that can change when new data or methods appear.
Kartu 452
Pertanyaan
How can behavioral differences cause isolation?
Jawaban
Different courtship signals reduce mating between populations.
Kartu 453
Pertanyaan
What evidence can test origin-of-life hypotheses?
Jawaban
Chemistry experiments, geological records, molecular comparisons, and plausible self-replicating or membrane-forming systems.
Kartu 454
Pertanyaan
How should fitness be compared in an experiment?
Jawaban
Measure relative reproductive contribution, such as viable offspring, under the same environmental conditions.
Kartu 455
Pertanyaan
What does the fossil record not provide?
Jawaban
A complete sample of every organism or every transitional population.
Kartu 456
Pertanyaan
How can a neutral trait change in frequency?
Jawaban
Genetic drift can shift it by chance, especially in small populations.
Kartu 457
Pertanyaan
How can drift reduce adaptive potential?
Jawaban
It can remove alleles and lower genetic diversity needed under future environmental change.
Kartu 458
Pertanyaan
Why does a large population support Hardy–Weinberg stability?
Jawaban
Chance sampling has less effect on allele frequencies, reducing drift.
Kartu 459
Pertanyaan
If A and B share a more recent node with each other than either shares with C, what does that mean?
Jawaban
A and B are sister taxa and share a more recent common ancestor with each other than with C.
Kartu 460
Pertanyaan
What is adaptive radiation?
Jawaban
Rapid diversification of one ancestral lineage into species using different ecological roles.
Kartu 461
Pertanyaan
What can experiments producing organic molecules from simple chemicals show?
Jawaban
That some building blocks can form under modeled conditions; they do not recreate or prove the exact origin of life.
Kartu 462
Pertanyaan
A correlation links beak size with survival. Why isn't causation settled?
Jawaban
Other traits or habitats may covary with beak size; controlled or multivariable evidence is needed.
Kartu 463
Pertanyaan
Why does agreement among fossils, anatomy, and molecules strengthen an evolutionary claim?
Jawaban
Independent evidence types pointing to the same history make alternative explanations less plausible.
Kartu 464
Pertanyaan
A drought favors deeper beaks. What must be measured to show selection?
Jawaban
Heritable beak variation and differences in survival or reproduction linked to beak depth.
Kartu 465
Pertanyaan
Why can artificial selection produce unintended traits?
Jawaban
Selected genes may be linked to other alleles, and inbreeding can expose harmful recessive alleles.
Kartu 466
Pertanyaan
What data are needed to test Hardy–Weinberg genotype expectations?
Jawaban
Population genotype counts or reliable genotype frequencies for the locus.
Kartu 467
Pertanyaan
Why doesn't one living species count as the ancestor of another on a typical tree?
Jawaban
Living tips represent lineages that have both evolved since their shared ancestral lineage.
Kartu 468
Pertanyaan
Why can reduced gene flow accelerate divergence?
Jawaban
Populations retain separate mutations, drift independently, and respond to different selective pressures.
Kartu 469
Pertanyaan
Why are ribozymes relevant to early-life hypotheses?
Jawaban
RNA can both store information and catalyze reactions, offering a possible bridge before modern DNA–protein systems.
Kartu 470
Pertanyaan
What makes an evolutionary argument strong?
Jawaban
A clear claim, relevant population-level evidence, and reasoning that connects inheritance and differential reproduction to the observed change.
Kartu 471
Pertanyaan
How can a directional response help an organism?
Jawaban
Moving toward resources or away from hazards can improve survival and reproduction.
Kartu 472
Pertanyaan
What is a trophic level?
Jawaban
A feeding position in the flow of energy through an ecosystem.
Kartu 473
Pertanyaan
What processes move carbon into and out of biological molecules?
Jawaban
Photosynthesis fixes carbon; respiration, decomposition, and combustion release carbon dioxide.
Kartu 474
Pertanyaan
What does exponential population growth assume?
Jawaban
Resources are effectively unlimited and the per-capita growth rate stays constant.
Kartu 475
Pertanyaan
What is a density-dependent limiting factor?
Jawaban
Its effect strengthens as population density rises, such as competition, disease, or predation.
Kartu 476
Pertanyaan
What is a keystone species?
Jawaban
A species whose ecological effect is disproportionately large relative to its abundance.
Kartu 477
Pertanyaan
What are three levels of biodiversity?
Jawaban
Genetic diversity, species diversity, and ecosystem diversity.
Kartu 478
Pertanyaan
What is the independent variable in a fertilizer–algae experiment?
Jawaban
The fertilizer amount or nutrient concentration deliberately changed.
Kartu 479
Pertanyaan
What shape represents exponential growth over time?
Jawaban
A J-shaped curve.
Kartu 480
Pertanyaan
What do primary producers do?
Jawaban
They capture external energy and build organic molecules from inorganic carbon.
Kartu 481
Pertanyaan
What is a density-independent limiting factor?
Jawaban
Its effect is not primarily set by population density, such as a severe freeze or wildfire.
Kartu 482
Pertanyaan
Why is nitrogen fixation necessary?
Jawaban
Most organisms cannot use atmospheric nitrogen gas directly, so it must be converted to biologically available compounds.
Kartu 483
Pertanyaan
What does logistic growth add to the exponential model?
Jawaban
Growth slows as population size approaches carrying capacity.
Kartu 484
Pertanyaan
What is gross primary productivity?
Jawaban
The total rate at which producers capture energy in organic matter.
Kartu 485
Pertanyaan
What is competition?
Jawaban
An interaction in which organisms using the same limited resource reduce one another's access or fitness.
Kartu 486
Pertanyaan
What is ecological succession?
Jawaban
Change in community composition after new habitat forms or a disturbance alters an existing community.
Kartu 487
Pertanyaan
What shape represents ideal logistic growth?
Jawaban
An S-shaped curve.
Kartu 488
Pertanyaan
What is net primary productivity?
Jawaban
Gross primary productivity minus producers' respiratory energy use.
Kartu 489
Pertanyaan
Why does genetic diversity matter for conservation?
Jawaban
It increases the range of inherited responses available under disease or environmental change.
Kartu 490
Pertanyaan
What organisms perform much biological nitrogen fixation?
Jawaban
Certain prokaryotes, including free-living and symbiotic bacteria.
Kartu 491
Pertanyaan
What is carrying capacity?
Jawaban
The population size an environment can sustain over time under current conditions.
Kartu 492
Pertanyaan
Why is net primary productivity important to consumers?
Jawaban
It is the producer biomass and energy available for growth and the next trophic levels.
Kartu 493
Pertanyaan
What is competitive exclusion?
Jawaban
Species with identical limiting-resource niches cannot coexist indefinitely under stable conditions.
Kartu 494
Pertanyaan
How do primary and secondary succession differ?
Jawaban
Primary succession begins without developed soil; secondary succession begins where soil remains.
Kartu 495
Pertanyaan
Why can carrying capacity change?
Jawaban
Resources, habitat, climate, competitors, disease, and disturbance can change.
Kartu 496
Pertanyaan
Why does available energy decline up a food chain?
Jawaban
Organisms use much energy for metabolism and lose it as heat and waste rather than storing it as biomass.
Kartu 497
Pertanyaan
What is an ecosystem service?
Jawaban
A benefit people receive from ecosystems, such as pollination, water purification, soil formation, or climate regulation.
Kartu 498
Pertanyaan
What does nitrification do?
Jawaban
Microbes oxidize ammonium to nitrite and then nitrate.
Kartu 499
Pertanyaan
What does per-capita growth rate measure?
Jawaban
Population change per individual per unit time.
Kartu 500
Pertanyaan
What is ecological efficiency?
Jawaban
The percentage of energy or production transferred from one trophic level to the next.
Kartu 501
Pertanyaan
What is resource partitioning?
Jawaban
Competing species use different resources, places, or times, reducing direct overlap.
Kartu 502
Pertanyaan
What is resilience in an ecosystem?
Jawaban
The ability to recover structure or function after disturbance.
Kartu 503
Pertanyaan
How is population growth estimated from births, deaths, immigration, and emigration?
Jawaban
Births + immigration − deaths − emigration.
Kartu 504
Pertanyaan
If producers store 10,000 kJ and primary consumers receive 10%, how much do they receive?
Jawaban
1,000 kJ.
Kartu 505
Pertanyaan
How does habitat fragmentation affect populations?
Jawaban
It shrinks and isolates habitat, reducing movement and gene flow while increasing edge effects.
Kartu 506
Pertanyaan
Why sample several sites within each habitat?
Jawaban
Replication captures spatial variation and reduces the chance that one unusual site drives the result.
Kartu 507
Pertanyaan
A population grows from 200 to 230 in one year. What is its percent growth?
Jawaban
15%, because the increase of 30 divided by 200 is 0.15.
Kartu 508
Pertanyaan
What is a circadian rhythm?
Jawaban
An internal roughly 24-hour cycle that environmental cues can reset.
Kartu 509
Pertanyaan
Why are food webs more realistic than simple food chains?
Jawaban
Most species eat or are eaten by multiple species, creating connected pathways.
Kartu 510
Pertanyaan
What does denitrification do?
Jawaban
Microbes convert nitrate to nitrogen gases, returning nitrogen to the atmosphere.
Kartu 511
Pertanyaan
What characterizes an r-selected life-history strategy?
Jawaban
Many offspring, early reproduction, and relatively low investment per offspring in variable environments.
Kartu 512
Pertanyaan
What is mutualism?
Jawaban
An interaction that benefits both species.
Kartu 513
Pertanyaan
What is resistance in an ecosystem?
Jawaban
The ability to remain relatively unchanged during disturbance.
Kartu 514
Pertanyaan
How can climate change shift species ranges?
Jawaban
Organisms track suitable temperature, moisture, seasons, or interacting species when movement is possible.
Kartu 515
Pertanyaan
What characterizes a K-selected life-history strategy?
Jawaban
Fewer offspring, later reproduction, and higher investment per offspring near carrying capacity.
Kartu 516
Pertanyaan
A population curve levels near 800. What does the model suggest?
Jawaban
About 800 is the carrying capacity under those measured conditions, not a permanent universal value.
Kartu 517
Pertanyaan
How can seasonal cues affect reproduction?
Jawaban
Changes such as day length can trigger hormonal and behavioral shifts timed to favorable conditions.
Kartu 518
Pertanyaan
What role do decomposers play?
Jawaban
They break down dead material and waste, returning nutrients to forms other organisms can use.
Kartu 519
Pertanyaan
Why can phosphorus limit ecosystems?
Jawaban
It is essential but often released slowly from rocks and lacks a large atmospheric gas phase.
Kartu 520
Pertanyaan
What does a Type I survivorship curve show?
Jawaban
High survival through early and middle life, followed by a steep decline at older ages.
Kartu 521
Pertanyaan
What is commensalism?
Jawaban
One species benefits while the other has no clear benefit or harm.
Kartu 522
Pertanyaan
Why can diversity improve ecosystem stability?
Jawaban
Multiple species or response types can keep functions going when one component declines.
Kartu 523
Pertanyaan
Why can overharvesting destabilize a population?
Jawaban
Removal faster than replacement lowers abundance and can alter age structure or genetic diversity.
Kartu 524
Pertanyaan
Predator and prey peaks alternate over time. What can the graph establish?
Jawaban
Their abundances covary with a lag; the graph alone cannot prove the predator caused every prey change.
Kartu 525
Pertanyaan
What is acclimation?
Jawaban
A reversible phenotypic adjustment by an individual to an environmental change.
Kartu 526
Pertanyaan
Does energy cycle through an ecosystem?
Jawaban
No. Energy flows through and is ultimately dissipated as heat; matter cycles.
Kartu 527
Pertanyaan
How does the water cycle connect ecosystems?
Jawaban
Evaporation, transpiration, condensation, precipitation, runoff, and infiltration move water and dissolved materials.
Kartu 528
Pertanyaan
What does a Type II survivorship curve show?
Jawaban
A roughly constant mortality risk across ages.
Kartu 529
Pertanyaan
What is parasitism?
Jawaban
A parasite benefits while reducing its host's fitness.
Kartu 530
Pertanyaan
What is an invasive species?
Jawaban
A nonnative species that spreads and causes ecological, economic, or human-health harm.
Kartu 531
Pertanyaan
How can a wildlife corridor help fragmented populations?
Jawaban
It supports movement, recolonization, and gene flow between habitat patches.
Kartu 532
Pertanyaan
How should biodiversity be compared when sample effort differs?
Jawaban
Standardize sampling effort or use a method that accounts for unequal effort before comparing.
Kartu 533
Pertanyaan
How does acclimation differ from adaptation?
Jawaban
Acclimation occurs within an individual; adaptation is an inherited population change across generations.
Kartu 534
Pertanyaan
How can removal of a top predator affect lower trophic levels?
Jawaban
It can trigger a trophic cascade by changing prey abundance and the organisms prey consume.
Kartu 535
Pertanyaan
Why can extra fertilizer cause low oxygen in water?
Jawaban
Nutrient enrichment drives algal growth; decomposition then consumes dissolved oxygen.
Kartu 536
Pertanyaan
What does a Type III survivorship curve show?
Jawaban
High early mortality with much better survival among those reaching later stages.
Kartu 537
Pertanyaan
How can predation maintain diversity?
Jawaban
A predator can prevent one strong competitor from dominating the community.
Kartu 538
Pertanyaan
How can disturbance increase or decrease diversity?
Jawaban
Its effect depends on frequency and intensity; it may create habitat variety or eliminate sensitive species.
Kartu 539
Pertanyaan
Why protect multiple habitats rather than one small reserve?
Jawaban
Different habitats, disturbances, and climate trajectories preserve more species and ecological options.
Kartu 540
Pertanyaan
A restoration site gains species but not nutrient cycling. How should success be evaluated?
Jawaban
Use both composition and ecosystem-function measures; one metric alone gives an incomplete result.
540 kartu
AP Biology Flashcards: Complete 8-Unit Course Review
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