Chapter15

Question 1

cell undergoes translation to produce what?

Answer 1

A polypeptide

Question 2

How do the protein polypeptides know where to go

Answer 2

they. have a signal (their amino acid sequence) that directs them to a specified location

Question 3

Proteins that are destined to go to the nucleus enter through what?

Answer 3

Through nuclear pores/gates

Question 4

Proteins that are destined to go to the chloroplast/mitochondria/peroxisome, or ER reach there how?

Answer 4

they are transported by translocators

Question 5

What is a translocator?

Answer 5

an ER membrane protein with a pore

Question 6

Proteins that move from the ER to other locations are transported how?

Answer 6

They are transported as cargo by vesicles

Question 7

To be directed to the ER, proteins must have what?

Answer 7

they must have ER singal

Question 8

Ribosomes do what to synthesize proteins that obtain the ER proteins

Answer 8

they attach themselves to the ER

Question 9

How do proteins with the ER signal enter the ER

Answer 9

they are synthesized through the Translocation channels

Question 10

What happens to all the other proteins that are not meant to go to the ER

Answer 10

they are synthesized by any free ribosomes

Question 11

what is an SRP

Answer 11

a signal recognition particle

Question 12

How is a ribosome directed to the ER

Answer 12

with a signal sequence and an SRP

Question 13

SRP slows what down

Answer 13

the synthesis of proteins

Question 14

SRP binds what

Answer 14

SRP binds the SRP receptor

Question 15

Soluble Protein are released into

Answer 15

the ER Lumen

Question 16

What happens to soluble proteins when they are released into the ER lumen?

Answer 16

they are modified and transported as secreted proteins

Question 17

What is the difference between soluble proteins and membrane proteins? (in the context of the ER)

Answer 17

Soluble proteins are released into the ER and transported as secreted proteins
whereas
Membrane proteins remain in the ER and are modified to remain membrane bound

Question 18

The process of Glycosylation of ER proteins involves the addition of what molecule (to what, and where)?

Answer 18

Oligosaccharides Molecule to specific amino acid residues-on polypeptide chains

Question 19

The addition of oligossaccharides to amino acids on polypeptide chains, occur during what?

Answer 19

Protein Synthesis

Question 20

In glycosylation, oligosaccharides are synthsized on which molecule?

Answer 20

Dichol

Question 21

Dichol is what kind of molecule

Answer 21

A lipid molecule

Question 22

During glycosylation, oligosaccharides are transferred from dichol molecules after synthesis to where?

Answer 22

to specific asparagine residues (on the polypeptide chain)

Question 23

The attachment of oligosaccharides to specific asparagine residues is known as what type of glycosylation

Answer 23

N-Linked Glycosylation

Question 24

What is the purpose of Glycosylation of ER proteins?

Answer 24

functions include;
-formation of glycoproteins
-immune responses
-cell adhesion

Question 25

What is the function of oligosaccharides?

Answer 25

-protects protein from degradation or guides it to other organelles or promotes cell recognition

Question 26

Proteins leave the ER and enter the golgi apparatus for what purpose?

Answer 26

further processing, sorting and modification of protein

Question 27

How do proteins leave the ER?

Answer 27

in transport vesicles

Question 28

Proteins enter the Golgi Apparatus where

Answer 28

at the Cis Face

Question 29

Proteins are sorted in the Golgi Apparatus based on waht?

Answer 29

based on the particular signals that are within the amino acid sequences of the protein - or the modification acquired during ER passage - these declare where they will be directed to (lysosomes. surface, or back to ER)

Question 30

Proteins that have undergone the effects of the Golgi Apparatus exit where?

Answer 30

Through the Trans Face

Question 31

Following the sorting of proteins in the Golgi Apparatus, what happens

Answer 31

Further oligosaccharide modification of proteins

Question 32

Proteins then leave the golgi apparatus and go where?

Answer 32

To the cell surface

Question 33

Endocytosis

Answer 33

process where cells ingest fluid, molecules, particles, other cells

Question 34

describe the mechanism of endocytosis

Answer 34

regions of the plasma membrane "pinch" inward creating an endocytic vesicle containing the engulfed material

Question 35

Pinocytosis

Answer 35

when a cell takes in small dissolved particles & liquid "cell drinkage" -this is followed by the cell membrane invaginating and formation of a small vesicle

Question 36

Phagocytosis

Answer 36

engulfment of larger particles, dead cells, or solid material - cell membrane extends via pseudopods; surrounding and engulfing particle -this forms a phagosome

Question 37

What is a Pseudopod

Answer 37

A temporary extension of a cell, used for cell movement or engulfing food

Question 38

Phagosomes

Answer 38

vesicles formed during phagocytosis that contains the engulfed particle

Question 39

Phagolysosomes

Answer 39

following the formation of a phagosome, the phagosome fuses with a lysosome -contents of phagosome are exposed to the digestive enzymes in a lysosome -engulfed material is broken down into smaller components

Question 40

What are the specialized phagocytic cells with surface receptors?

Answer 40

Macrophages Neutrophils

Question 41

Following phagocytosis, the phagosome moves where?

Answer 41

to the cells cytoplasm

Question 42

What type of endocytosis provides a specific route into animal cells?

Answer 42

Receptor-Mediated Endocytosis

Question 43

What triggers Receptor-Mediated Endocytosis?

Answer 43

the binding of LDL to its receptors

Question 44

what is the primary site of intracellular digestion

Answer 44

Lysosomes

Question 45

What are endosomes?

Answer 45

membrane bound vesicles involved in endocytosis, sorting, recyling/degradation

Question 46

What is transcytosis

Answer 46

The transport of substances in, across and then out of cells

Question 47

Misfolded proteins are properly folded by what?

Answer 47

Chaperone Proteins

Question 48

If chaperone proteins fail to fold ER proteins properly, what happens to the proteins?

Answer 48

They are degraded

Question 49

Following protein modification, proteins leave the Golgi Apparatus and go where?

Answer 49

to the cell's surface