CyCh. 17 Pt. 1 - Cytoskeleton

These flashcards cover key terms and concepts associated with the cytoskeleton and microtubules, including their structure, functions, and roles in cellular processes.

What is the Cytoskeleton?

A complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells.

What are Microtubules?

Long rigid tubes that maintain cell shape and facilitate transport within the cell.

What is the function of the Microtubule Organizing Center (MTOC)?

Protects the '– end' of microtubules and allows for initial formation.

What are Protein filaments?

Long chains of protein monomers that form the cytoskeleton.

Define Dynamic instability in microtubules.

A property where microtubules rapidly reorganize the cytoskeleton by alternating between growth and shrinking.

What is a Vesicle?

A small, fluid-filled internal cellular compartment.

What are Cilia?

Hairlike protrusions from cell surfaces that contribute to particle movement using microtubules.

What is the role of Flagella?

Hairlike organelles that provide motility to sperm and protozoans.

List one function of the Cytoskeleton.

Cell shape maintenance and support.

What is one of the three essential components of the cell's skeleton?

Microtubules.

What are Microtubules composed of?

Heterodimers of α- and β-tubulin.

How does GTP affect microtubules?

GTP-bound β-tubulin allows for growth; GDP-bound β-tubulin leads to shrinking.

What determines microtubule growth or shrinkage?

The rate of GTP hydrolysis relative to the rate of tubulin addition.

What happens when the GTP cap depletes on microtubules?

It causes disassembly or catastrophe of the microtubule.

What is microtubule polarity?

Refers to the orientation of microtubules with a slower '– end' and a rapid '+ end'.

What proteins are involved in regulating the dynamics of microtubules?

Microtubule-associated proteins (MAPs).

What is the consequence of tau protein dissociation in Alzheimer's Disease?

It contributes to microtubule depolymerization and neurofibrillary tangles.

What are microtubule targeting agents used for?

To modify dynamic instability and prevent cell division in cancer treatments.

What do Kinesins transport along microtubules?

Cellular cargo such as synaptic vesicles, mitochondria, and viruses.

What is the primary function of Dyneins?

To move cargo towards the '– end' of microtubules.

How do Kinesins use ATP?

They utilize ATP to 'walk' along microtubules and transport materials.

What is the structural arrangement of microtubules in Cilia and Flagella?

A '9+2' array of microtubules.

What role do accessory proteins play in microtubules?

They aid in microtubule stability and movement.

How do Cilia and Flagella enable cell movement?

Through a propagated bending motion made possible by dynein motor proteins.

What is a key characteristic of the formation of microtubules?

It is dynamic and regulated by various proteins.

What is the impact of dynein on microtubules?

It mediates the sliding of microtubules against each other, allowing bending.

How do motor proteins transport vesicles?

By moving along microtubules over long distances.

What cellular structures are supported by the Cytoskeleton?

All eukaryotic cell organelles and tissues.

What types of cells rely on the Cytoskeleton?

Muscle cells, neurons, epithelial cells, white blood cells, and cancer cells.

What happens during chromosome segregation?

Microtubules aid in the proper separation of chromosomes during cell division.

In which ways do microtubules affect signal transduction?

They aid in the cellular ability to transmit signals effectively.