cytoskeleton

Question 1

what is cytoskeleton

Answer 1

network of protein polymers in the cell which provide mechanical support for the ecll

Question 2

cytoskeletal protiens

Answer 2

actin
intermmediate filaments
microtubels

Question 3

function of the cytoskeleton

Answer 3

acts as muscle/skeleton for the cell
cell migration
organelle movement
mechanical support 
shape/organisation of the cell

Question 4

where are actin filaments found

Answer 4

everywhrer

concentrated under the membrane

Question 5

size of the protein polymerns

Answer 5

actin smallest

microtubule biggest

Question 6

actin

Answer 6

can form microvilli/lamelipodia

carry out cellular moments, phagocytosis, cytokinesis, muscle contraction

Question 7

what is actin constituents

Answer 7

G actin

F actin

Question 8

what occurs during phagoytosis

Answer 8

rearrangement of the acid cytoskeleton

Question 9

stages of actin polymerisation

Answer 9

nucleation - formation of actin nucleus
elongation - monomers added at the positive end
steady state

Question 10

what is phalloidin

Answer 10

toxin which targets cytoskeletal protiens

Question 11

what does phalloidi do

Answer 11

blocks F actin

therefore stops actin and depolymerisation

Question 12

what is and does cytochalasin do

Answer 12

fungal protein
stops actin polymerisation
cells unable to take things up

Question 13

what are intermediate filaments

Answer 13

nuclear and cytoplasmic meshworks

maintain shape

Question 14

types of intermediate filaments

Answer 14

keratins
lamina
desmin

Question 15

keratin

Answer 15

heteropolymer (type I and II protiens)
pairing of protein is specific
pairing predictive of: differentiation status and epithelial proliferation

Question 16

where does a keratin mutation occur

Answer 16

K14 or K5

cells separate

Question 17

what is immunohistochemistry

Answer 17

antibody based staining technique

Question 18

microtubules

Answer 18

strong hollow tubes
heterodimer
polarised and dynamic
structural suppot

Question 19

molecular motors

Answer 19

microtubules used as anchor

transport vessels e.g. vesicles move along the microtubles

Question 20

microtubules in cell division

Answer 20

mitotic spindle = microtubule and microtubule dependant motor proteins
attatch to chromosomes at kinetochores
dyenein moves kinetochore poleward along

Question 21

what can microtubles bundles form

Answer 21

cilia and flagella

Question 22

how do actin and microtubules work together

Answer 22

microtubules direct actin assembly

Question 23

cell juncitions

Answer 23

tight junction
desmosomes
hemidesomosomes
adherans junctions
gap junctions

Question 24

functions of cell junctions

Answer 24

tight junction - cell adherence, water tight seal
adherans junction - connects actin filament bundle with adjacent cells
gap junctions - allows flow of ions and water between cells
desmosomes - connects intermmediate filaments between adjecent cells
hemidesomosomes - connect intermediate filaments to ECM

Question 25

what are microtubule interacting drugs and fucntion

Answer 25

taxol
binds and stablises microtubles (chromosomes don’t move)
cells die by apoptosis

colchicine
prevents cell migration