Cytoskeleton

Question 1

Types of cytoskeleton

Answer 1

Microfilaments (actin), microtubules (tubulin), intermediate filaments

Question 2

Microfilament structure

Answer 2

~7nm in size
Globular, monomers into Filamentous polymers

Question 3

Microfilament organisation

Answer 3

Distributed throughout cytosol but concentrated at cell edge/cortex

Question 4

Microfilament function

Answer 4

1) Stabilisation of PM/CM (eg microvilli)
2) Intracellular movement - pushing (exocytosis- “treadmilling”) and pulling (adhesion belt/contractile ring/vesicles - endocytosis) forces on PM

Question 5

Microtubule structure

Answer 5

Associated with proteins which stabilise them (MAPS)

Question 6

Microtubule organisation

Answer 6

Depends on microtubule organising centres (MTOC)

Question 7

Microtubule function

Answer 7

Intracellular transport and organisation:
Kinesin
Dynein

Question 8

I.f. structure

Answer 8

Fibrous, filamentous

Question 9

I.f. organisation

Answer 9

Extend from nuclear envelope to PM, make up nuclear lamina, support nuclear envelope

Question 10

I.f. function

Answer 10

1) control of assembly of protein monomers
2) control of nucleus structure and assembly
3) strength (different for different types of cells)
4) clinical uses (eg- identifying cancerous tumours)