Test 4 Flashcards Preview

Cellular Biology > Test 4 > Flashcards

Flashcards in Test 4 Deck (132)
Loading flashcards...
1

_____ bud from RER with no ribosomes.

Vesicles

2

What is an organelle that is surrounded by a double membrane?

Autophagy

3

What are the roles of phagocytosis?

Uptake of large food particles by single celled organisms. Uptake and destruction of pathogens in animals.

4

The 3 major steps in phagocytosis include:

1 Plasma membrane folds enclose the food or pathogens.
2. The folds fuse to produce a vacuole or phagosome that pinches off inwardly.
3. Phagosomes fuse with a lysosome and the material is digested.

5

In the Cisternal Maturation Model, Golgi enzymes are carried in a _____ direction in what? While Cargo is moved ___ and is what?

retrograde, transportation vesicles; in and is restricted to cisternae.

6

What is a family of small GTP-binding proteins that specifically tether vesicles to targets by recruiting tethering proteins?

Rabs

7

_____ constitute a family of more than 35 membrane proteins.

SNAREs

8

The toxins responsible for ______ and ____ act as proteases whose only known substrates are specific SNAREs.

botulism and tetanus

9

Cleavage of the SNAREs that are specific to boulism and tetanus prevent the ___________ and ___________. Both toxins cause paralysis and cause death.

fusion of vesicles, release of neurotransmitters

10

a lipid carrier molecule on which oligosaccharides are assembled prior to transfer to specific asparagine residues on ER membrane proteins

Dolichol Phosphate

11

The sequence of Dolichol Phosphate sugars depends on the sequence of _________ that participate in making the oligosaccharide and the location of the specific enzymes within the membranes of the secretory pathway.

glycosyltransferases

12

During Glycosylation in the Golgi Complex, most ________ are removed and ____ are added sequentially by glycotransferases as in the ER.

mannose residues, sugars

13

Sugars added during Glycosylation in the Golgi Complex are added to the ______ attached to the ______.

oligosaccharide, polypeptide

14

Glycosylation in the Golgi Complex occurs as the ___________.

polypeptide moves through the stacks

15

What can result due to Glycosylation in the Golgi Complex?

Varied oligosaccharides

16

The Golgi complex is the site of Glycosylation and the ___________ including glucosaminoglycan chains of proteoglycans, pectins and hemicellulose.

synthesis of complex carbohydrates

17

______ move materials from the ER “forward” to the ERGIC (ERG intermediate complex) and Golgi complex.

COPII-coated vesicles

18

COPI-coated vesicles move materials in a ______ direction from the Golgi complex to the ERGIC and ER, and from the Trans Golgi cisternae to the cis cisternae.

retrograde

19

________ move materials from the TGN to endosomes, lysosomes, and vacuoles.

Clatherin-coated vesicles

20

For maintenance of organelle membrane proteins, ________ are excluded from transport vesicles.

Resident proteins

21

_____ are short amino acid sequences that bind receptors which capture the protein and return them to the ER in COPI-coated vesicles.

Retrieval sequences

22

_____ consists of three light and three heavy chains joined to form a three legged triskelion. Each leg of the triskelion extends along two edges of a polygon.

Clathrin

23

Each leg of clathrin ends in a ____________ where it engages an adaptor.

hook that projects toward the surface

24

The adaptor at the end of a clathrin leg is a __________ that attaches to the _____.

transmembrane protein, lignin

25

With this disease, patient’s contain lysosomes bloated with undigested materials. Due to an N acetyl glucosamine phosphotransferase deficiency. The enzyme places a mannose-6phosphate “address” on lysosomal proteins.

I-cell disease

26

These disorders are due to a lac of a single lysosomal enzyme causing undigested substrate to accumulate.

Lysosomal storage disorders

27

____ is a Lysosomal storage disorder due to a deficiency in β-N-hexosaminidase. This enzyme digests a major lipid componet of the membranes of brain cells.

Tay-Sachs

28

Gaucher's disease is a Lysosomal storage disorder due to

glucocerebroside lipids accumulating in macrophages.

29

_____ is involved in Gaucher's disease, the gluycocerebrosidase with mannose residues is removed, so the enzyme goes to macrophages not the liver cells.

Enzyme replacement therapy

30

A ______ protein on a vesicle interacts with a _____ on the target membrane forming a four stranded α-helical bundle that brings the two membranes into contact.

v-SNARE, t-SNARE