Chapter 17 The Cytocekeleton Flashcards Preview

BIOS 222 with Kay and Wherpa > Chapter 17 The Cytocekeleton > Flashcards

Flashcards in Chapter 17 The Cytocekeleton Deck (27):
1

What is actin-binding protein?

Protein that interact with actin monomers or filaments to control the assemble behavior and structure of actin filaments and networks.

2

Describe Actin Filaments and their function in the cell?

They are thin and flexible. They are made from globular actin molecules that assemble in a polar direction. These filaments are essential of cell movement and contraction of muscle cells.

3

What is the cell cortex?

A layer of the cortex on the inner layer of the plasma membrane that gives strength and structure to the cells. In animals it is rich with actin filaments. These filaments govern the shape of the cell and drive cell movement.

4

What are centrioles?

A cylindrical array of microtubules usually found in the pairs at the center of a centrosome in animal cells. They are also found at the the base if cilia and flagellum where they are called basal bodies.

At the center of the cell surrounded by the centrosome.

5

What is a centrosome?

The microtubule-organizing center that sits near the nucleus in an animal cell. During cell division this structure duplicates to form two poles of the biotic spindle. It surrounds the centrioles. It is where the IF shoot off from.

6

What are cilium?

Hairlike structures made of microtubules found on the surface of many eukaryotic cells. When they are present in large numbers, their rhythmic beating can drive fluid over the cell surface as in the epithelium of the lung.

7

Where do bundles of intermediate filament connect to other cells

At the desmosomes. It is here that an indirect mechanical link is established from cell to cell.

8

What is dynamic instability?

Microtubles rapid shifting between growth and shrinking.

9

What is dynein?

A motor protein that uses ATP to move toward the minus end of the a microtubule.

Also responsible for the bending of the cilia.

10

What is filopodium?

Long actin containing extension ont eh surface of that animal cell. Sometimes has an exploratory function.

11

Describe the flagellum

Long, whiplike structure capable of propelling a cell though a fluid membrane with its rhythmic beating. While bacterial flagella are totally different, in eukaryotic flagella are really just long cilia.

12

How many strands are in actin filaments?

8

13

what are keratin filaments?

A type of intermediate protein abundant in epithelial cells, where it provides tensile strength. Main structural component of hair, feathers and claws.

14

What is kinesin?

A family of motor protein that uses ATP to move toward the plus end of the microtubule. Away from the cell center.

15

Describe microtubules?

Long, stiff cylindrical structure composed of tubulin.
Functions:
1.) Organize the interior of the cell
2.) Drive intracellular transport
3.) Position organelles in they cytoplasm
4.) Inside cilia and flagella

16

What are motor proteins?

Myosin, kinesin, dynein. that use ATP to propel itself along protein filaments.

17

Describe myofibril?

Long, cylindrical structure that constitutes the contractile element of a muscle cell. Contracted mostly of actin and myosin.

18

What is myosin?

A type of motor protein that uses ATP to drive movement along actin filaments.

Works with actin to from skeletal muscle.

19

What are myosin filaments?

Made if myosin-II. Interaction of actin promote contraction of muscle.

20

Describe nuclear lamina?

It is a meshwork that underlies and strengthens the. It is made of Intermediate Filaments

21

Why is polarity discussed in chapter of the cytoskeleton?

Because Actin and Microtubules are polar meaning they have a front and back. Also, the plus end of microtubules is responsible for defining the polarity of the cell.

22

What is the Rho protein family?

Control the organization of actin cytoskelton

23

Describe sarcomere?

Highly organized assembly of actin and myosin filament hat serves as the contractile unit of a myofibril in a muscle cell.

24

What is tubulin?

Monomer from which microtubules are made.

25

Describe intermediate filaments.

Forms rope-like networks that help resist tension applied from outside the cell. The strongest of the cytoskeletal structures.

26

What type of cytoskeletal structure is only in vertebrates?

Intermediate filaments. Because it is for structures that need a lot ability to resist stretching from the outside.

27

What is the ratio of a mirotunule bundle?

9:2