Cell structure pt. 2 (exam 2)

Question 1

what’s the difference between translating mRNA on a ribosome on the rough ER vs a ribosome that’s loose in the cytoplasm

Answer 1

• if you’re being made on the membrane you’ll have something to do with the membrane
  ex:
• embedded in membrane
• secreted
• part of organelles that are surrounded by a membrane
  ex: free enzyme or a protein used by the exoskeleton

Question 2

function of ribosomes found on the surface of the rough ER

Answer 2

they carry out translation

Question 3

function of kinesin in microtubules

Answer 3

• transport of vesicles

anterograde vs retrograde

Question 4

anterograde

Answer 4

toward cell membrane (moving something out of the cell)

Question 5

retrograde

Answer 5

toward cell body

Question 6

_____ triggers retrograde

Answer 6

rabies

Question 7

list the structure of a kinesin

Answer 7

tail = affinity for transport vesicles
stalk= 2 strands, twisted,tension buildup
head

Question 8

briefly explain how kinesins work

Answer 8

• “walks along a microtubule track”

- walks the vesicle all the way to the end

Question 9

vesicle transport is _____

Answer 9

highly enzyme dependent

Question 10

microtubules: centrosomes and kinetochore

FUNCTION

Answer 10

• direction of chromosome movement

- highly ATP dependent

Question 11

centrosome

Answer 11

• microtubule

- contains the centrioles from which the spindle fibers develop

Question 12

kinetochore

Answer 12

• microtubule
• provides the major attachment point for the spindle microtubules during mitotic or meiotic division to pull the chromosomes apart

Question 13

Colchicine at higher doses

Answer 13

• treat inflammatory response
• for cancer
• interferes w microtubule formation, therefore can’t form spindle fibers and stops mitosis

Question 14

colchicine at lower doses

Answer 14

• can harm immune cells
• blocks the highway, affects transport
• used for immune diseases

Question 15

which cells are the most susceptible for colchicine

Answer 15

the ones that are doing the most work

Question 16

cilia, flagella, and dynein

Answer 16

• directs movement of cell or movement of material over cell surface
• microtubules

Question 17

Dynein

Answer 17

• partly embedded in tubulin fiber
• microtubule based
• power a wide variety of motile processes within eukaryotic cells (includes cilia and flagella)

Question 18

cilia

Answer 18

• 2 types: non motile and motile
• on the surface of many cells
• hair like, helps move things across the surface of a cell

Question 19

flagella

Answer 19

• motility organelle that enables movement and chemotaxis

Question 20

basement membrane and function

Answer 20

• this is in the ECM

- anchors down the epithelium to its loose connective tissue

Question 21

location of basement membrane

Answer 21

between the epidermis and the dermis.

Question 22

integral membrane proteins

Answer 22

proteins that span the entire length of the membrane

Question 23

what connects the ICM to the ECM

Answer 23

laminin

fibronectin

Question 24

what happens when you increase the laminin ratio

Answer 24

increases cellular quiescence (when cells don’t replicate)

Question 25

passive or active transport? | endocytosis

Answer 25

active

Question 26

passive or active transport? | exocytosis

Answer 26

active

Question 27

passive or active transport? | cell membrane or the sodium-potassium pump

Answer 27

active

Question 28

passive or active transport? | osmosis

Answer 28

passive

Question 29

passive or active transport? | diffusion

Answer 29

passive

Question 30

passive or active transport? facilitated diffusion

Answer 30

passive

Question 31

diffusion

Answer 31

the movement of molecules with a gradient - passive process - doesn't require energy

Question 32

osmosis

Answer 32

- the diffusion of water across a membrane | - small quantities of water do diffuse

Question 33

what does kidney filtration depend on?

Answer 33

certain cells being impenetrable to water

Question 34

facilitated diffusion is also known as

Answer 34

carrier-mediated transport

Question 35

facilitated diffusion

Answer 35

- passive transport - uses integral membrane proteins as channels - demonstrates specificity (Ex: Na+, K+, water, etc) - can be open to allow free diffusion or closed (Gated) to restrict diffusion

Question 36

aquaporins

Answer 36

- non gated channels that allow for osmosis - open channels

Question 37

distribution of aquaporins in kidney membranes are regulated by..

Answer 37

hormones

Question 38

active transport

Answer 38

- moves against gradient - uses pumps to concentrate molecules - requires energy - utilizes integral membrane proteins

Question 39

receptor mediated endocytosis

Answer 39

- stimulated by specific ligand binding receptor molecules - receptors have G protein signaling (use 2nd messengers) - triggers vesicle formation by clathrin - requires energy

Question 40

explain clathrin binding

Answer 40

- clathrin binding is stabilized by adaptors.

Question 41

dynamin

Answer 41

- clips off the vesicle in receptor mediated endocytosis

Question 42

pinocytosis

Answer 42

- endocytosis - intake of extracellular fluid - requires energy vesicle formed through the action of actin fibers

Question 43

explain endocytosis via receptor mediated/viral attack

Answer 43

1. viral particles bind to receptors 2. tricks cell into internalizing virus 3. virus entry is specific to cell receptors (there's specificity to attack) requires energy

Question 44

exocytosis

Answer 44

- transport vesicles released from golgi - anchored to membrane by SNARE complex - fusion causes secretion of contents - can be constant or unregulated

Question 45

regulated exocytosis

Answer 45

requires a signal Ca2+ | - has to trigger SNARE