Week 7

Question 1

animal specific cell stuff (2)

Answer 1

extracellular matrix
lysosome

Question 2

extracellular matrix

Answer 2

specialized material outside cell

Question 3

lysosome

Answer 3

degradation of cellular components that are no longer needed

Question 4

plant cell specific architecture (3)

Answer 4

cell wall
vacuoles
chloroplast

Question 5

vacuole types

Answer 5

degradation (like animal lysosome)
storage

Question 6

cytoplasm vs cytosol vs lumen

Answer 6

cytoplasm = everything in cell outside nucleus
cytosol = aqueous part of cytoplasm (not inside organelles)
lumen = inside of organelles

Question 7

lipids in membrane and common feature

Answer 7

glycolipids, sterols, phospholipids
glycerol group = phosphoglycerides

Question 8

phospholipid / phosphoglyceride structure

Answer 8

different group
+
phosphate make up polar head
glycerol
hydrocarbon tails

Question 9

hydrocarbon tail

Answer 9

14-24 carbons
saturated and unsaturated

Question 10

liposome and it’s uses (3)

Answer 10

artificial lipid bilayer
1. lipid properties
2. membrane protein properties
3. drug delivery

Question 11

What affects membrane fluidity?

Answer 11

1. temperature
2. composition
   saturation (cis-double bonds increase fluidity)
   tail length (shorter tails interact less and increase fluidity)
   cholesterol in animal cells (stiffens membrane)

Question 12

sterols

Answer 12

animals - cholesterol (up to 1:1 ratio to phospholipids)
plants - plant sterols, some cholesterol

Question 13

scramblase and its purpose

Answer 13

phospholipid translocator
catalyzes RANDOM flipping between leaflets
because phospholipids are synthesized in cytosolic leaflet of ER to get symmetrical bilayer

Question 14

flipase

Answer 14

catalyzes SPECIFIC phospholipid flipping to cytosolic leaflet, often creating assymetry
in golgi membrane

Question 15

glycosylation

Answer 15

adding sugar on luminal golgi face, end up on cytosolic facing leaflet

Question 16

integral membrane proteins

Answer 16

transmembrane, monolayer associated, lipid linked

Question 17

peripheral membrane proteins

Answer 17

protein-attached
bound to other proteins, lipids, or by non-covalent interactions
gentle extraction

Question 18

How are protein structures identified?

Answer 18

x-ray crystallography
hydrophobicity plot

Question 19

GPI anchor

Answer 19

synthesis in ER lumen, end up on cell surface

Question 20

lateral diffusion

Answer 20

diffusion within leaflet

Question 21

FRAP

Answer 21

Fluorescence Recovery After Photobleaching
see protein movement and restriction
GFP = green fluorescent protein