cell biology 5 Flashcards
1
Q
what are microfilaments made from and what do they do
A
- actin polymers
- thicken the cortex around the inner edge of a cell
- resist tension
2
Q
what are microtubules made from and what do they do
A
- tubular polymers
- interior of the cell
- maintain cell shape by resisting compressive forces
3
Q
what are intermediate filaments made of and what do they do
A
- things such as keratin polymers
- throughout the cell
- hold organelles in place
4
Q
what is the structure of microfilaments
A
- 8mm wide right handed helix
- plus and minus ends
- globular actin subunits
5
Q
what are the types of cytoplasmic projections
A
- lamelipodia
- filopodia
- microvilli
- neuron projections
6
Q
what are the functions of microfilaments
A
- cytoplasmic projections
- anchoring and mobility of cell membrane proteins
- maintain cell shape
- phagocytosis
- regulate organelle disturbance and cytoplasmic flow
- muscle cell contractile apparatus
7
Q
when does treadmilling occur
A
- at specific monomer
- rate of gain at plus end = rate of loss at minus end
- steady state
- net flux of monomer through tubule
8
Q
what is the fast growing end of a microfilament
A
plus end
9
Q
what is the slow growing end of a microfilament
A
minus end
