ER

Question 1

…………..: membrane bound with a specific and essential function, found in……….

Answer 1

organells, eukaryaotes

Question 2

the simplest prokaryotic cell is ………., it contains ……genes, it was the first to study

Answer 2

E.coli
4000

Question 3

Saccharomyces cerevisiae is a ……….,it is a eukaryote cell with short cycle

Answer 3

yeast

Question 4

C-elegans used to study the ………of the cell, in immature worms the number of cell is ………than the number in mature worm

Answer 4

differntiation and death,
larger

Question 5

dorosphila……….. used to study cell differtiation as well,
………..have the same number of human genome

Answer 5

melanogaster,
mice

Question 6

major components of cells are nucleic acid, proteins, carbs, and……………(50 percent of membranes, …….percent of mitochondrial membrane)

Answer 6

lipids
30

Question 7

molecules in the cell interact with each other ……………….

Answer 7

non-covalently

Question 8

the largest organel following the nucleus is……….., it is attached to the nucleus and to………

Answer 8

ER
Golgi appartus

Question 9

if a protein is synthesized in free ribosomes, it will stay in the ………….., or be transported to………….or………or mitochondria

Answer 9

cytosol
nucleus
peroxisomes

Question 10

if a protein contain a signal on the …. terminus, it will be ……….to……..

Answer 10

N
translocated to ER

Question 11

the synthesized protein in the bound ribosome enter the ER lumen to continue the synthesis, it might stay there or be transported to……….., or to golgi after that to ……..then to ………..finally to the plasma membrane

Answer 11

nucleus
endosomes
lysosomes

Question 12

if the synthesized protein will be transported to the outside, this will happen via………..
the signal will cleave after………..

Answer 12

secretory vesicles
transfer to the ER lumen

Question 13

if a protein is bound to the perioxisomal membrane it was synthesized in ………….ribosomes, but if it enters the peroxisome it was synthesized in…………

Answer 13

bound
free ribosomes

Question 14

the directed ribosomes to the ER will first complete tranlation on the surface of ER then it will interact with a channel protein called……………..,
then this protein will allow the………….of the synthesized protein

Answer 14

translocon
entry (to ER lumen)

Question 15

in the ER the signal will be ……………….by ………….. in a hydrolysis reaction

Answer 15

cleaved
peptidase

Question 16

which organelles have proteins that enters to the ER lumen?

Answer 16

ER, lysosomes, golgi, secretory proteins to the plasma membrane

Question 17

membranous protein are inserted in th ER membrane, then it will be translocated to ………..or…………….membranes

Answer 17

plasma
peroxisomes
etc

Question 18

if the N terminus was inside the lumen of ER it will be in……….when tranlocated to…………membrane

Answer 18

outer side
plasma

Question 19

when does the polypeptide cahin translocation stops?

Answer 19

when a transmembrane sequence will be recognized by translocon

Question 20

what will happen if the sequence was flipped?

Answer 20

the both terminus will be flipped also

Question 21

if there were multiple of transmembrane sequences what will happen?

Answer 21

multi transmembrane domains of the protein

Question 22

inside the ER, what happens to the protein?

Answer 22

folding(chaperons)
complex quaternary
disulfide bond
glycosylation
anchoring by lipids

Question 23

which enzyme forms disulfide bonds? where do they form?

Answer 23

disulfide protein isomerase
between 2 cystine residues

Question 24

ERAD system contains ubiquination, what does it mean?

Answer 24

adding ubiquting in the cytosol to the misfoled protein in order to be degraded by proteosomes

Question 25

SER is a major site for synthesis of?

Answer 25

-membrane glycerophospholipids
-sphingophospholipids (ceramides, glycolipids)
-steroids

Question 26

SER is abundant in which organs? what its rule there?

Answer 26

liver(excerting drugs)
ovaries and testes(steroid hormones)

Question 27

ERGIC stands for?
what its order in transporting from ER to golgi?

Answer 27

ER-golgi intermediate compartment
ER–>transport vesicles fuse to–>ERGIC—>golgi

Question 28

KDEL sequence let the protein to?
what is this sequence?

Answer 28

retaiin to ER
lys-asp-glu-leu