nervous system notes

Question 1

what is the nervous system?

Answer 1

master controlling and communication system

Question 2

how does the nervous system communicate?

Answer 2

via electricity and chemicals (neurotransmitters)

Question 3

sensory input

Answer 3

gathered by sensory receptors

Question 4

integration

Answer 4

processing of sensory input

Question 5

motor output

Answer 5

activation of effector organs (muscles and glands)

Question 6

what two regions are in the CNS?

Answer 6

Central
Peripheral

Question 7

where is the PNS located

Answer 7

outside of the CNS

Question 8

spinal nerves

Answer 8

to and from the spinal cord (there are 31)

Question 9

cranial nerves

Answer 9

to and from the brain (there are 12)

Question 10

functions of PNS

Answer 10

Sensory
Motor

Question 11

sensory

Answer 11

somatic
visceral

Question 12

somatic

Answer 12

from skin and skeletal muscles and joints to CNS

Question 13

visceral

Answer 13

from visceral organs

Question 14

motor

Answer 14

somatic
autonomic

Question 15

somatic nervous system

Answer 15

voluntary: conscious control of skeletal muscles

Question 16

autonomic

Answer 16

regulates smooth muscle, cardiac muscle and glands

Question 17

sympathetic

Answer 17

fight or flight

Question 18

parasympathetic

Answer 18

brings body back to normal state

Question 19

neuroglia cell types

Answer 19

neuroglia
neurons

Question 20

neuroglia of CNS

Answer 20

astrocytes
microglial cells
ependymal cells
oligodendrocytes

Question 21

astrocytes

Answer 21

controls the environment around neurons

Question 22

microglial cells

Answer 22

cleans up around the neurons

Question 23

ependymal cells

Answer 23

line cavities of brain and spinal chord - moves cerebral spinal fluid

Question 24

oligodendrocytes

Answer 24

insulates nerves in the CNS - provide the myelin sheaths

Question 25

neuroglial of PNS

Answer 25

satellite cells Schwan cells

Question 26

neurons

Answer 26

extreme longevity amniotic, with few exceptions high metabolic rate

Question 27

tracts

Answer 27

bundles of neuron processes in CNS

Question 28

nerves

Answer 28

bundles of neuron processes in PNS

Question 29

axon

Answer 29

- starts at axonal hillock - long axons are called nerve fibers - far ends are called axon terminals - secrete neurotransmitters - myelin sheath

Question 30

myelin sheath

Answer 30

- protects and electrically insulates the axon - increases speed of conduction - gaps - axon colladerals emerge - white matter - regions of the brain and spinal chord with lots of mylenation - gray matter - non myelinated fibers

Question 31

structural classification of dendrites

Answer 31

multipolar bipolar unipolar

Question 32

sensory

Answer 32

sends signals to the brain

Question 33

motor

Answer 33

sends signals away from the brain

Question 34

interneurons

Answer 34

almost all are in the CNS; association neurons

Question 35

Neurons can ______ change their resting membrane potential

Answer 35

Rapidly

Question 36

Neurons are

Answer 36

Highly excitable

Question 37

Membrane ion channels are

Answer 37

Large proteins, and specific k+ channels that only allow pass through

Question 38

leakage/nongated channels

Answer 38

always open

Question 39

Gated channels

Answer 39

Part of the protein changes shape to open/close channel

Question 40

Chemically (ligand)

Answer 40

Open only with binding of a specific chemical

Question 41

Voltage

Answer 41

Open and close in response to changes in membrane potential

Question 42

Mechanically

Answer 42

Open and close in response to physical deformation of sensory receptors

Question 43

When channels are open

Answer 43

Ions diffuse quickly from high to low, move towards opposite charges

Question 44

Resting membrane

Answer 44

- ⭐ Approx: -70 mV ⭐ - Cytoplasmic side Negatively charged relative to the outside - Range -40 mV to -90 mV - Is said to be polarized (separation of charges)

Question 45

Generating membrane potential depends on

Answer 45

- Differences in sodium ion and potassium ion concentration - Differences in permeability

Question 46

Membranes are impermeable to

Answer 46

large anionic proteins

Question 47

Slightly permeable to

Answer 47

Na+ → into cell

Question 48

25 more permeable to

Answer 48

K+ → out of cell

Question 49

Quite permeable to

Answer 49

Cl-

Question 50

More __ diffuses out than __ in

Answer 50

- K+, Na+ - Inside of cell is more negative

Question 51

Sodium potassium pump stabilizes

Answer 51

Membrane potential

Question 52

Resting potential change when

Answer 52

- Concentrations change - Permeability changes

Question 53

Changes produce 2 types of signals

Answer 53

- Graded potentials - Action potentials

Question 54

Graded potentials

Answer 54

- Short distances - Short lived - localized changes in membrane potential - Triggered by - stimulus that opens gated ion channels - Named by location and function - Current flows quickly but decays, only over short distances

Question 55

Action potentials

Answer 55

- Long distances - Brief reversal of membrane potential - Do NOT decay - Also called nerve impulse Principal way neurons send signal, only over long distances

Question 56

Depolarization

Answer 56

Move toward zero and above, become more positive

Question 57

Hyperpolarization

Answer 57

Move away from zero, become more negative

Question 58

Generation of AP

Answer 58

Look at graph on paper