Neurons and Neuroglia

Question 1

these are the signaling units of the NS

Answer 1

neurons

Question 2

these are the support cells

Answer 2

neruoglia

Question 3

what is the function of a neuron

Answer 3

excitable cells for reception of stimuli and conduction of nerve impulses

Question 4

where are neurons found

Answer 4

brain and SC

Question 5

can neurons replicate ?

Answer 5

does not undergo cell division

Question 6

what are the 4 regions of a neuron

Answer 6

cell body or soma
dendrites
axon
presynaptic terminals

Question 7

what is the function of the cell body

Answer 7

metabolic center and contains the nucleus sa cytoplasm bounded by PM

Question 8

what are the 2 kinds of processes a cell body gives rise to

Answer 8

axon and dendrite

Question 9

describe the structure of dendrites

Answer 9

several and short and they branch out like trees

Question 10

function of dendrites

Answer 10

receives incoming signals from other cells; TOWARDS the cell body

Question 11

function of axons

Answer 11

carries signal to other neurons; AWAY from cell body

0.1 mm to 2m

Question 12

describe structure of axons

Answer 12

single, long and tubular

Question 13

what is the significance of the initial segment of an axon

Answer 13

first 50-100 um; specialized trigger region near origin where AP are initiated then propagated down the axon

Question 14

how are neurons classified

Answer 14

number, length, mode of branching neurites and size

Question 15

structure of pseudounipolar neuron

Answer 15

spherical body with single process that bifurcates into central and peripheral branches

branches have same structure and function of an axon

Question 16

example of pseudounipolar

Answer 16

posterior root ganglion

Question 17

structure of bipolar

Answer 17

elongated, spindle cell body with single emerging neurites on each end

Question 18

example of bipolar

Answer 18

retinal cells, vestibular and cochlear ganglion cells

Question 19

structure of multipolar

Answer 19

one long axon and multiple dendrites

most of the cells in CNS

Question 20

where are multipolar found

Answer 20

most of the cells in CNS

Question 21

structure of golgi type 1

Answer 21

long axons that can stretch 1m or more

Question 22

examples of golgi type 1

Answer 22

pyramidal cells of cerebral cortex, purkinje of cerebellar cortex and motor cells of SC

Question 23

structure of golgi type 2

Answer 23

short axons that terminate in the vicinity of the cell body or absent

star shaped - multiple short dendrites

Question 24

function of golgi type 2

Answer 24

often inhibitory and mas madami sha sa type 1

Question 25

function of nucleus

Answer 25

metabolic center of neuron and stores DNA

Question 26

can mature neurons replicate?

Answer 26

nope only functions in gene expression

Question 27

function of nucleolus

Answer 27

synthesizes rRNA and assists in ribosome subunit assembly; large due to high rate of protein synthesis

Question 28

function of nuclear envelope

Answer 28

continuous w cytoplasmic RER; double layered w nuclear pores

Question 29

what is the the PM

Answer 29

continuous external boundary of the cell and its processes

Question 30

in EM how does the PM appear as

Answer 30

2 dark lines with light line in between

Question 31

what is the structure of the PM

Answer 31

inner and outer layer very loosely arranged protein molecules separated by a middle lipid layer

Question 32

discuss the structure of the lipid layer

Answer 32

rows of phospholipid molecules with hydrophobic ends in contact with protein layers

Question 33

function of hydrophilic channels

Answer 33

allows ions to pass through

Question 34

significance of carbohydrates to the PM

Answer 34

attached to the outside of plasma membrane and are linked to the proteins or lipids

Question 35

what is formed through the attachment of carbohydrates in the PM

Answer 35

forming a cell coat or glycocalyx

Question 36

what are the 2 confrontational states of sodium and potassium channels

Answer 36

open and closed

Question 37

what is gating and when does it occur

Answer 37

twisting of channel widening the lumen - response to voltage change, ligand, stretch or pressure