Ch 4 Subcellular Organization of the Nervous System

Question 1

Why are transcription levels so high in neurons?

Answer 1

because protein synthesis needs to be high due to the extensive volume of axons/dendrites

Question 2

Where is mRNA synthesized?

Answer 2

nucleus

Question 3

Nissl Substance

Answer 3

stacks of rough endoplasmic reticulum interposed with rosettes of free polysomes

Question 4

axon length

Answer 4

from a few micrometers to a meter or more

Question 5

Nodes of Ranvier

Answer 5

high density sodium channels in unmyelinated axonal gaps

Question 6

axolemma

Answer 6

the cell membrane surrounding an axon

Question 7

paranodal axoglial junctions

Answer 7

These flank the nodes of Ranvier. They help regulate the sodium channels.

Question 8

DRG

Answer 8

Dorsal Root Ganglia

Question 9

2 categories of membrane proteins

Answer 9

integral and peripheral

Question 10

integral membrane proteins

Answer 10

neurotransmitter receptors and ion channels are embedded in the lipid bilayer or covalently bonded to molecules close to the layer

Question 11

secretory pathway

Answer 11

1. integral membrane proteins and secretory proteins are synthesized in the RER. 2. Golgi apparatus packages into secretory granules. 3. released by exocytosis

Question 12

N terminus

Answer 12

the start of a protein or polypeptide terminated by an amino acid with a free amine group

Question 13

synthesis of integral proteins

Answer 13

like secretory pathway, but an SRP jacks the N terminus

Question 14

SRP

Answer 14

Signal Recognition Particle

Question 15

translocon

Answer 15

conceptualized aqueous pore on the RER

Question 16

TRAM

Answer 16

translocating chain-associating membrane protein

Question 17

TRAP

Answer 17

translocon-associated protein

Question 18

ribonucleic protein

Answer 18

a signal recognition particle

Question 19

lumen

Answer 19

inside space of a tubular structure

Question 20

TGN

Answer 20

trans-Golgi network: proteins are targeted to plasma membrane or organelles

Question 21

de Novo

Answer 21

from the beginning, afresh

Question 22

Adaptins

Answer 22

Adaptor Proteins (AP) transport vesicles from golgi

Question 23

AP1-4

Answer 23

AP 1 & 2 have clathrin coated vesicles. AP 1 & 4 move vesicles between TGN and endosomes. AP 2 is for endocytosis. AP 3 ferries cargoes to lysosomes.

Question 24

endosomes

Answer 24

any compartment in a eukaryotic cell

Question 25

2 types of cell membrane invagination

Answer 25

caveola and clathrin

Question 26

caveola

Answer 26

threadlike protein caveolin on the surface of a cell for endocytosis.

Question 27

oligodendrocytes

Answer 27

glial cells that help insulate or support axons