Cellular biochem

Question 1

RER

- what protein modifications

Answer 1

N-linked oligosac addition

Question 2

smooth ER function

- what cells rich in them

Answer 2

• steroid synthesis
• detox of drugs and poisons
• liver (for detox) and adrenal cortex/gonads (for hormones)

Question 3

Golgi

- what protein modifications

Answer 3

• N-oligosac on asparagine
• O-oligosac on Ser and Thr
• adds M6P to proteins meant for lysosome

Question 4

anterograde vesicular trafficking

Answer 4

COP-II (ER to golgi)

Question 5

retrograde vesicular trafficking

Answer 5

COP-I (golgi to ER)

Question 6

peroxisome function

Answer 6

catabolism of:

• very long chain FA’s
• branched FAs

Question 7

I-Cell disease

• what is it
• mechanism
• features

Answer 7

• inclusion cell disease
• inherited lysosomal storage d/o
• golgi doesn’t do M6P
• coarse facial features, clouded corneas, restricted joint movement, high plasma levels of lyosomal enzymes

Question 8

retrograde molecular motor protein

Answer 8

dynein (+ to -)

Question 9

anterograde molecular motor protein

Answer 9

kinesin (- to +)

Question 10

actin and myosin used for what?

Answer 10

muscle contraction
microvilli
cytokinesis
adherens junctions

Question 11

intermediate filaments used for?

Answer 11

structural components:

vimentin, desmin, cytokeratin, lamins, glial fibrillary acid proteins (GFAP)

Question 12

Vimentin immunohistological stains what?

Answer 12

Vimentin in connective tissue

Question 13

Desmin immunohistological stains what?

Answer 13

Muscle

Question 14

Cytokeratin immunohistological stains what

Answer 14

Epitheliail cells

Question 15

GFAP immunohistological stains what?

Answer 15

neuroglia

Question 16

collagen type I

• where?
• decreased production in what

Answer 16

bone, tendon, fascia, skin
dentin
cornea
late wound repair

decreased in osteogenesis imperfecta type I

Question 17

collagen type Ii

where?

Answer 17

cartilage
vitreous body
nucleus pulposus

Question 18

collagen type III where?
def in what ?

Answer 18

reticulin
skin
blood vessels
uterus
fetal tissue
granulation tissue

def in vascular Ehlers-Danlos syndrome

Question 19

collagen type IV where?

Answer 19

basement MB
basal lamina
lens

Question 20

Elastin rich in what aa’s

Answer 20

proline and glycine

Question 21

Fibrillin

- def in what

Answer 21

glycoprotein that forms sheath around elastin

- Marfan

Question 22

in starvation situations, what does liver convert into glucose (3)

Answer 22

1. alanine
2. lactate
3. glycerol