Citoesqueleto Flashcards
What is the primary function of the cytoskeleton?
The primary function of the cytoskeleton is to provide structural support, shape, and organization to the cell.
True or False: Microfilaments are composed of actin.
True
Fill in the blank: Microtubules are primarily composed of __________.
tubulin
What are the three main components of the cytoskeleton?
Microfilaments, intermediate filaments, and microtubules.
Which component of the cytoskeleton is involved in muscle contraction?
Microfilaments
What is the diameter range of microtubules?
Microtubules have a diameter of about 25 nanometers.
Multiple Choice: Which of the following is NOT a function of intermediate filaments? (a) Mechanical support (b) Cell motility (c) Anchoring organelles
b) Cell motility
What role do microtubules play in cell division?
Microtubules form the mitotic spindle that separates chromosomes during cell division.
True or False: Intermediate filaments are more stable than microtubules.
True
What are the two main types of microfilaments?
Actin filaments and myosin filaments.
Fill in the blank: The dynamic instability of microtubules refers to their ability to __________.
rapidly grow and shrink
Which protein is primarily associated with microfilament function?
Actin
What is the role of the cytoskeleton in cell signaling?
The cytoskeleton helps transmit signals from the cell surface to the interior, affecting cellular responses.
Multiple Choice: Which of the following is a characteristic of microfilaments? (a) Hollow tubes (b) Solid rods (c) Intermediate thickness
b) Solid rods
What is the main structural role of intermediate filaments?
To provide mechanical strength and support to cells.
True or False: Microtubules are involved in the transport of organelles within the cell.
True
What is the role of the centrosome in relation to microtubules?
The centrosome serves as the main microtubule organizing center in the cell.
Fill in the blank: The polymerization of actin filaments is regulated by __________.
actin-binding proteins
What are the two main types of microtubule-associated proteins?
MAPs (Microtubule-Associated Proteins) and motor proteins.
Multiple Choice: Which of the following is a function of microtubules? (a) Cell shape maintenance (b) Muscle contraction (c) Cell division
c) Cell division
What is the significance of the plus and minus ends of microtubules?
The plus end is where growth occurs, while the minus end is where disassembly occurs.
True or False: Intermediate filaments are not involved in cell motility.
True
What is the role of dynein and kinesin in relation to microtubules?
Dynein and kinesin are motor proteins that transport cellular cargo along microtubules.
Fill in the blank: The main function of actin filaments is to facilitate __________.
cell movement and shape changes
What is the relationship between the cytoskeleton and cellular signaling pathways?
The cytoskeleton interacts with signaling pathways to regulate cell behavior and responses.
Multiple Choice: Which component of the cytoskeleton is the largest in diameter? (a) Microfilaments (b) Intermediate filaments (c) Microtubules
c) Microtubules
What is the role of the actin cortex?
The actin cortex provides mechanical support and determines cell shape.
True or False: Microfilaments can form networks that assist in cellular movement.
True
What are lamellipodia and filopodia?
Lamellipodia are broad, sheet-like extensions, while filopodia are thin, spike-like extensions formed by actin filaments.
Fill in the blank: The primary function of the nuclear lamina is to provide __________ to the nucleus.
structural support
What type of cell junctions are associated with intermediate filaments?
Desmosomes
Multiple Choice: Which of the following is a characteristic feature of microtubules? (a) They are dynamic (b) They are rigid (c) They are fixed in length
a) They are dynamic
What is the role of actin in cell division?
Actin forms the contractile ring that helps separate daughter cells during cytokinesis.
True or False: Microtubules are static structures that do not change.
False
What is the function of the mitotic spindle?
To segregate chromosomes during cell division.
Fill in the blank: The process of microtubule assembly is known as __________.
polymerization
What is the significance of the actin-myosin interaction?
It is crucial for muscle contraction and various cellular movements.
Multiple Choice: Which cytoskeletal component is involved in intracellular transport? (a) Microfilaments (b) Intermediate filaments (c) Microtubules
c) Microtubules
What is the role of spectrin in the cytoskeleton?
Spectrin is involved in maintaining the shape and stability of the plasma membrane.
True or False: Microtubules are essential for maintaining cell shape.
True
What is the primary structural protein of intermediate filaments?
Vimentin, keratin, or neurofilament proteins, depending on the cell type.
Fill in the blank: Microtubules are organized into __________ structures.
hollow cylindrical
What is the role of the extracellular matrix in relation to the cytoskeleton?
The extracellular matrix provides external support and interacts with the cytoskeleton to influence cell behavior.
