Nervous Tissue 15 Flashcards Preview

Anatomy & Physiology - Kuntzman > Nervous Tissue 15 > Flashcards

Flashcards in Nervous Tissue 15 Deck (49)
1

What does the Central Nervous System (CNS) consis of

brain and spinal cord

2

What does the Peripheral nervous system consist of

-consists of cranial and spinal nerves that contain both sensory and motor fibers

-connects CNS to the  muscles, glands & all sensory receptors

3

Dermatome

cutaneous area developed from one embryonei spinal cord segment and recieving most of its sensory innervation from one spinal nerve. 

4

Myotome

group of muscle sinnervated by the motor neruons of a single spinal segment

5

motor neuron

neurons that conduct impulses from th ebrain toward the psinal cord or out of the brain and spinal cord into cranial or spial nerves to effectors that may be wither muscles of glands.  Asl known as efferent neurons

6

How many pairs of cranial nerves

12

7

how many pairs of spinal nerves emerge from the spinal cord

31

8

Ganglia

n(located outside the brain and spinal cord), are small masses of nervous tissue, containing primarily cell bodies of neurons.

9

Plexuses

nPlexuses crossing over of nerves to backup function e.g. Enteric plexuses help regulate the digestive system.

10

Sensory receptors

nSensory receptors are either parts of neurons or specialized cells that monitor changes in the internal or external environment.

11

How many pairs of cranial nerves exit in the cervial

8

12

How are the nerves named

from the vertebrae that they exit

13

Describe what the sensory function of nerves mean

nSensory function: to detect changes in the internal and external environment through specialized receptors.

qSensory (afferent) neurons (nerve cells) serve this function.

14

afferent

sensory

15

efferent

motor

16

What are beroreceptors

the mech by which we have a feedback loop for blood pressure

17

What purpose do interneurons serve

nIntegrative function: to analyze the sensory information, store some aspects, and make decisions regarding appropriate behaviors.

qAssociation or interneurons serve this function.

18

______________ is to respond to stimuli by initiating action.

motor function

19

What is the functional unit of the nervous system

neuron

20

define slow axonal transport

movement of materials from the cell body to the axon terminals

  • movement in one direction only -- away from cell body
    • movement at 1-5 mm per day

21

define fast axonal flow

  • moves organelles & materials along surface of microtubules
  • at 200-400 mm per day
  • transports in either direction
  • for use or for recycling in cell body

22

Purkinji cell

cell shape- highly branching dendrites

in cerebellum

23

Pyramidal cells

found in the cerebral cortex

pyramid chaped cell bodies

24

What is the most coomon type of cell found in the CNS

neuroglia

25

Which  cell of the CNS is analgous to the schwann cells of the PNS

glial cells

26

______________ myelinate (wrap around) axons in the PNS during fetal development

Schwann cells

27

n saltatory conduction

– a leap frog action of the action potential that speeds up transmission

28

What allows for saltatory conduction

myelinated axons

29

nodes of Ranvier

the gaps in the myelin sheath which appear at intervals along the axon

30

if the nerve is cut, what may limit the re growth of the nerve

the myelin sheath grows back faster than the nerve

31

Organization of the nervous system

which system 

motor neurons to skeletal muscle tissue

SNS - Somatic nervous system

voluntary

32

Organization of the Nervous system

which system 

is invouluntary from snsory neurons from visceral organs to CNS

ANS - Autonomi nervous system

motor neurons to smooth an cardiac muscle an dglands

 

 

33

What does they sympathetic division of the ANS do

speeds up heart rate

34

What does the parasympatetic division of the ANS do

slows down heart rate

35

Organization of the Nervous system

which  system

is involuntary sensory and motor neruons which control the GI tract

ENS

Entric Nervous system

 

36

____________ neurons dunction independently of ANS & CNS

ENS

37

Why are neurons electrically excitable

due to their voltage difference across their membrane

38

Electrical signals in neurons

what are the two types of electric signals 

  • action potentials that can travel long distances
    •  
    • graded potentials that are local membrane changes only

39

What are Leakage channels

they allow a small steady stram of ions to leak across the mb following the electrochemical gradient

40

due to leakage channels, which ion is membrane more permeable to 

K+

41

What is the resting mb potential in nerve tissue

-70mV

42

List the four different types of ion channels in neurons

  1. Leakage channels
  2. Ligand-gated channels
  3. voltage gated channels
  4. mechanically gated ion channels

43

Which kind of gated ion channel responds to mechanical vibration or pressure

Mechanical

44

Which type of ion gated channel responds to a direct change in the membrane potential

voltage gated channels

45

Which type of channel opens and closes in response to a stimulus

Ligand gated channels

results in neuron excitability

46

___________ ions along inside of cell membrane & _______ ions along outside

Negative ions along inside of cell membrane & positive ions along outside

47

What are the 2 reasons that action potentials exist

  1. conentration of ions different inside and out
  2. mb permiabiltiy differs for Na+ & K+

48

Grated potentials

short distance signals

volage diminishes with distance

49

Action potentials

long distance signals

voltage does not diminish with distance