Cytoskeleton Flashcards: Fibers, Motors & Functions
Practice cytoskeletal fibers, motor tracks, cell division, and ciliary patterns with 50 English flashcards and short checks for ambiguous clues.
Mayelana naleli qoqo
Practice cytoskeleton structure and function with 50 English flashcards for secondary and introductory-college biology. The focus is on telling actin filaments, microtubules, and intermediate filaments apart, then applying those distinctions to motors, cell structures, and short reasoning prompts. Basic cell knowledge is helpful; the cell organelle flashcards cover that prerequisite.
The cards map filament names to building proteins and structural properties, selected protein or shape clues back to filament families, motor names to tracks and specified travel directions, and named cell structures to their cytoskeletal components. Short error checks distinguish a fiber from its building protein or motor. Other prompts ask what information is missing when support, movement, cell division, vesicle transport, or ATP use does not identify a unique answer.
Start with the three filament families, their assembly, and polarity. Motor tracks and ATP use lead into the actin cortex, microvilli, keratins, nuclear lamins, the spindle, and the animal-cell contractile ring. Basic ciliary architecture and selected motor-direction exceptions then support the final mixed distinctions. Selected reverse prompts and related variants are separated; the review scheduler handles longer-term spacing. Every card carries the cytoskeleton tag.
This is text-based recall practice. It does not test diagram or micrograph identification. Exhaustive reverse cards, arbitrary name-to-example lists, exact filament diameters, detailed motor families, clinical diagnosis, drug treatment, bacterial cytoskeletons, and molecular regulation pathways are excluded to keep the deck focused. Typical ciliary patterns are taught with exceptions, not as universal motility rules. No complete biology course or examination alignment is claimed.
The questions, explanations, sequence, and metadata were written independently with AI assistance. Scientific facts were checked against research publications on cytoskeletal interactions and intermediate filaments, microtubule dynamics, motor proteins, microvilli, animal-cell cytokinesis, actin assembly, cell protrusion, motile cilia, and primary cilia. Source wording, exercises, and diagrams were not copied; those publications retain their own licenses, and scientific facts are not claimed as proprietary. Original material and the AI-generated decorative cover are dedicated under CC0 1.0 to the extent applicable rights exist. The cover is an abstract illustration, not a molecular diagram. This is independent study material without institutional endorsement.
Amakhadi akuleli qoqo
Ikhadi 1
Umbuzo
What are the three major cytoskeletal filament families in animal cells?
Impendulo
Actin filaments (microfilaments), microtubules, and intermediate filaments.
Ikhadi 2
Umbuzo
Which protein builds microfilaments?
Impendulo
Actin.
Ikhadi 3
Umbuzo
Which two tubulin subunits pair to build microtubules?
Impendulo
Alpha-tubulin and beta-tubulin. Each building unit is an alpha–beta tubulin dimer.
Ikhadi 4
Umbuzo
Do all intermediate filaments use the same building protein?
Impendulo
No. Different cells use different intermediate-filament proteins, such as keratins, vimentin, and nuclear lamins.
Ikhadi 5
Umbuzo
What does filament polarity mean in the cytoskeleton?
Impendulo
The two ends have different molecular structures. Plus and minus label distinct ends, not electrical charges.
Ikhadi 6
Umbuzo
What is the basic shape of an actin filament?
Impendulo
Two intertwined strands of actin subunits. It is a thin filament, not a hollow tube.
Ikhadi 7
Umbuzo
Which major cytoskeletal filament forms a hollow tube?
Impendulo
A microtubule.
Ikhadi 8
Umbuzo
Which major cytoskeletal filament has a rope-like assembly of fibrous proteins?
Impendulo
An intermediate filament.
Ikhadi 9
Umbuzo
Which cytoskeletal filament is the track for myosin motors?
Impendulo
An actin filament.
Ikhadi 10
Umbuzo
Which major cytoskeletal filament family lacks distinct plus and minus ends?
Impendulo
Intermediate filaments. Actin filaments and microtubules are polar.
Ikhadi 11
Umbuzo
What directly powers the stepping of myosin, kinesin, and dynein motors?
Impendulo
ATP hydrolysis.
Ikhadi 12
Umbuzo
Which two motor-protein families move along microtubules?
Impendulo
Kinesins and dyneins.
Ikhadi 13
Umbuzo
Which filament network is especially prominent in the cortex just beneath an animal cell’s plasma membrane?
Impendulo
Actin filaments. The cortex helps control cell shape and surface mechanics.
Ikhadi 14
Umbuzo
Keratin networks belong to which cytoskeletal filament family?
Impendulo
Intermediate filaments.
Ikhadi 15
Umbuzo
What is microtubule dynamic instability?
Impendulo
Switching between growth and shrinkage. A microtubule can change length as tubulin subunits are added or lost.
Ikhadi 16
Umbuzo
A cargo moves by kinesin along a microtubule. Which component is the motor?
Impendulo
Kinesin. The microtubule is the track.
Ikhadi 17
Umbuzo
Which filaments form the supporting bundles inside microvilli?
Impendulo
Actin filaments.
Ikhadi 18
Umbuzo
Which proteins form the nuclear lamina beneath the inner nuclear membrane?
Impendulo
Lamins, members of the intermediate-filament protein family.
Ikhadi 19
Umbuzo
Which cytoskeletal filaments form the mitotic spindle?
Impendulo
Microtubules. Spindle microtubules help organize and separate chromosomes.
Ikhadi 20
Umbuzo
Cytoplasmic dynein carries cargo toward which end of a microtubule?
Impendulo
The minus end.
Ikhadi 21
Umbuzo
Which filament and motor form the main contractile machinery of the animal-cell cleavage ring?
Impendulo
Actin filaments and myosin II.
Ikhadi 22
Umbuzo
How can actin assembly help a crawling cell extend its leading edge?
Impendulo
Growing actin filaments can push the plasma membrane outward.
Ikhadi 23
Umbuzo
Which filaments form the axoneme, the internal framework of eukaryotic cilia and flagella?
Impendulo
Microtubules.
Ikhadi 24
Umbuzo
Conventional kinesin-1 carries cargo toward which end of a microtubule?
Impendulo
The plus end.
Ikhadi 25
Umbuzo
What mechanical role do intermediate-filament networks provide when a cell is stretched?
Impendulo
They help distribute tensile stress and resist damage from stretching.
Ikhadi 26
Umbuzo
In an animal-cell contractile ring, is myosin II a motor or an actin building subunit?
Impendulo
A motor. Actin supplies the filament subunits.
Ikhadi 27
Umbuzo
What does the typical 9 + 2 pattern of an airway motile cilium describe?
Impendulo
Nine outer microtubule doublets around two central single microtubules.
Ikhadi 28
Umbuzo
Does the name kinesin alone guarantee plus-end-directed movement?
Impendulo
No. Kinesin families differ; some move toward minus ends. Specify the kinesin type before assigning a direction.
Ikhadi 29
Umbuzo
How do the core filaments of microvilli differ from those of eukaryotic cilia?
Impendulo
Microvilli have actin bundles; cilia have a microtubule-based axoneme.
Ikhadi 30
Umbuzo
The nuclear lamina is built from which major filament family?
Impendulo
Intermediate filaments, specifically lamins.
Ikhadi 31
Umbuzo
In animal-cell division, which structure constricts the cell surface: the spindle or the contractile ring?
Impendulo
The contractile ring. Its actin–myosin machinery narrows the cleavage furrow.
Ikhadi 32
Umbuzo
What is a common role of a non-motile primary cilium?
Impendulo
Sensing and coordinating signals. It acts as a specialized signaling compartment.
Ikhadi 33
Umbuzo
Which motor family drives sliding between neighboring microtubule doublets in a motile cilium?
Impendulo
Axonemal dyneins. Structural constraints convert that sliding into bending.
Ikhadi 34
Umbuzo
Does vesicle transport by itself identify a microtubule track?
Impendulo
No. Vesicles can use microtubules or actin-based transport. The motor identity or filament composition supplies a better clue.
Ikhadi 35
Umbuzo
A prompt asks for the filament family containing keratin. Is keratin alone the requested answer?
Impendulo
No. Answer intermediate filaments. Keratin names a building protein, not the filament family.
Ikhadi 36
Umbuzo
What microtubule pattern is commonly used to describe a primary cilium?
Impendulo
The 9 + 0 pattern: nine outer doublets without a central pair. It is a typical description, not a universal rule for every cross-section.
Ikhadi 37
Umbuzo
A filament is assembled from alpha–beta tubulin dimers. Which filament family is it?
Impendulo
Microtubules.
Ikhadi 38
Umbuzo
What does the centrosome do for microtubules in many animal cells?
Impendulo
It acts as a microtubule-organizing center, helping nucleate and organize the microtubule array.
Ikhadi 39
Umbuzo
A vesicle is moved by myosin. Which filament supplies its track?
Impendulo
Actin. Myosin-based cargo transport uses actin filaments.
Ikhadi 40
Umbuzo
Why can’t a 9 + 0 axoneme alone establish that a cilium is non-motile?
Impendulo
Motile embryonic nodal cilia are a counterexample. Arrangement alone does not establish motility.
Ikhadi 41
Umbuzo
What extra clue would help identify a fiber described only as supporting cell shape?
Impendulo
Its protein composition or a specific structure it forms. All three major filament systems contribute to cell mechanics.
Ikhadi 42
Umbuzo
Why is the claim that all intermediate filaments lie in the cytoplasm incorrect?
Impendulo
Lamins form the nuclear lamina inside the nucleus.
Ikhadi 43
Umbuzo
In a 9 + 2 axoneme, does the 9 count nine individual microtubules?
Impendulo
No. It counts nine outer doublets. The central 2 counts two single microtubules.
Ikhadi 44
Umbuzo
An ATP-powered motor uses either actin or microtubules. What missing information would identify its track?
Impendulo
The motor family. Myosins use actin; kinesins and dyneins use microtubules. ATP use alone does not distinguish them.
Ikhadi 45
Umbuzo
What missing detail would distinguish fibers described only as helping animal-cell division?
Impendulo
The division structure or step. Spindle fibers are microtubules; the contractile ring contains actin.
Ikhadi 46
Umbuzo
A student says microvilli are miniature cilia because both project from the cell. What core-filament correction is needed?
Impendulo
Microvilli are supported by actin bundles; cilia have a microtubule-based core. Surface shape alone does not make them the same structure.
Ikhadi 47
Umbuzo
In microtubule-based transport, how does the filament’s role differ from the motor’s?
Impendulo
The microtubule supplies a track; kinesin or dynein supplies motor activity.
Ikhadi 48
Umbuzo
What extra detail is needed to identify a cytoskeletal system described only as enabling cell movement?
Impendulo
The type of movement. Actin supports crawling; microtubules and dyneins support ciliary or flagellar motion.
Ikhadi 49
Umbuzo
Is it accurate to say that microtubules have no role in animal-cell cytokinesis because the ring uses actin?
Impendulo
No. Microtubules also help coordinate cytokinesis, including positioning and organizing the division machinery.
Ikhadi 50
Umbuzo
Is the cytoskeleton a permanent, unchanging scaffold?
Impendulo
No. Its filaments and networks can assemble, disassemble, and reorganize as the cell’s needs change.
amakhadi angu-50
Cytoskeleton Flashcards: Fibers, Motors & Functions
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