CYTOSKELETON

Question 1

INTRO

Answer 1

a network of filaments known as the cytoskeleton (literally, “cell skeleton”),

• supports the plasma membrane
• gives the cell an overall shape
• aids in the correct positioning of organelles
• provides tracks for the transport of vesicles
• allows the cell to move.

Question 2

MICROFILAMENTS

Answer 2

They have a diameter of about 7 nm
are made up of many linked monomers of a protein called actin, combined in a structure that resembles a double helix.
Because they are made of actin monomers, microfilaments are also known as actin filaments.

Question 3

MF FUNCTIONS

Answer 3

in animal cell division, a ring made of actin and myosin pinches the cell apart to generate two new daughter cells.
When the actin and myosin filaments of a sarcomere slide past each other in concert, your muscles contract.
Actin filaments do transport , including protein-containing vesicles and even organelles.
Actin filaments can assemble and disassemble quickly, and this property allows them to play an important role in cell motility (movement),
actin filaments play key structural roles in the cell. In most animal cells, a network of actin filaments is found in the region of cytoplasm at the very edge of the cell. This network, which is linked to the plasma membrane by special connector proteins, gives the cell shape and structure

Question 4

INTERMEDIATE FILAMENTS

Answer 4

Intermediate filaments made of multiple strands of fibrous proteins wound together.
intermediate filaments have an average diameter of 8 to 10 nm, in between that of microfilaments and microtubules

Question 5

IMF FUNCTION

Answer 5

keratin, a fibrous protein found in hair, nails, and skin

and their jobs include maintaining the shape of the cell and anchoring the nucleus and other organelles in place.

Question 6

MICROTUBULES

Answer 6

microtubules are the largest of the three types of cytoskeletal fibers, with a diameter of about 25 nm.
A microtubule is made up of tubulin proteins arranged to form a hollow, straw-like tube, and each tubulin protein consists of two subunits, α-tubulin and β-tubulin.

Question 7

MT FUNCTIONS

Answer 7

hey provide tracks for motor proteins called kinesins and dyneins,

Question 8

FLAGELLA

Answer 8

Flagella (singular, flagellum) are long, hair-like structures that extend from the cell surface and are used to move an entire cell, such as a sperm. If a cell has any flagella, it usually has one or just a few.
9 INTO 2 array of MT

Question 9

CILIA

Answer 9

Motile cilia (singular, cilium) are similar, but are shorter and usually appear in large numbers on the cell surface. When cells with motile cilia form tissues, the beating helps move materials across the surface of the tissue. For example, the cilia of cells in your upper respiratory system help move dust and particles out towards your nostrils.
9INTO 2 array of MT

Question 10

BASAL BODY

Answer 10

The basal body is made of microtubules and plays a key role in assembly of the cilium or flagellum. Once the structure has been assembled, it also regulates which proteins can enter or exit^7
7
start superscript, 7, end superscript.
The basal body is actually just a modified centriole

Question 11

CENTRIOLES

Answer 11

A centriole is a cylinder of nine triplets of microtubules, held together by supporting proteins. Centrioles are best known for their role in centrosomes, structures that act as microtubule organizing centers in animal cells. A centrosome consists of two centrioles oriented at right angles to each other, surrounded by a mass of “pericentriolar material,” which provides anchoring sites for microtubules
The centrosome is duplicated before a cell divides, and the paired centrosomes seem to play a role in organizing the microtubules that separate chromosomes during cell division. However, the exact function of the centrioles in this process still isn’t clear. Cells with their centrosome removed can still divide, and plant cells, which lack centrosomes, divide just fine.