Nervous system organization

Question 1

What are the main roles of the nervous system?

Answer 1

Gathers, interprets, and transmits info between tissues

Question 2

Main role of CNS + structures

Answer 2

• brain receives/processes sensory info, coordinates response, store memories, thoughts and emotions
• spinal cord: conduct signal to and from brain + reflexes

Question 3

What is CSF and where is it found

Answer 3

• brain and spinal cord
• cushioning/shock absorber, nutrient transport
• blood barrier since blood doesn’t touch brain

Question 4

Types of matter in brain/spinal cord

Answer 4

• White: myelinated parts of neurons - axons
• Grey: unmyelinated and places where connections form - dendrites, axon terminals, synapses
• More grey matter = more connections = smarter… so more wrinkles in brain = smarter

Question 5

Main role of PNS + structures

Answer 5

• sensory receptors: take in stimuli (towards CNS)
• motor output: respond to signals caused by stimuli (away from CNS)

Question 6

Somatic NS

Answer 6

branch of PNS -> motor neurons
- voluntary mvmt

Question 7

Autonomic NS

Answer 7

branch of PNS -> motor neurons
autonomic: involuntary

Question 8

sympathetic NS

Answer 8

branches of PNS -> motor neurons -> autonomic
- fight or flight

Question 9

parasympathetic NS

Answer 9

branches of PNS -> motor neurons -> autonomic
- rest or digest

Question 10

Notes about nerve SIGNALS

Answer 10

binary and one-way

Question 11

What are nerves composed of and what do they generally do?

Answer 11

NEURONS carry electrical impulses called action potentials in ONE DIR.

Question 12

What are glial cells?

Answer 12

Glial cells are non-neurotic cells that provide support… ex:
- Schwann cells: produce myelin
- Astrocytes: supports nerve network, nutrient supply

Question 13

Dendrites

Answer 13

• The receiving end of a neuron
• Info can come from MULTIPLE neurons, or sensory cells

Question 14

Cell Body

Answer 14

contains most organelles and mitochondria (ATP needed for Na/K pump, in synapses to package neurotransmitters into vesicles and reuptake of NRTMs)

Question 15

Axon

Answer 15

Long trunk of neuron where action potential takes place. The connection btw cell body and axon is the AXON HILLOCK

Question 16

Action potentials

Answer 16

Quick flips of Na+ and K+ in and out the axon through “organized diffusion”

Question 17

Myelin

Answer 17

A set of fatty acids secreted by Schwann ells to insulate axons electrical signal
–> similar to rubber outside of electrical wires

Question 18

Nodes of Ranvier

Answer 18

Gaps of exposed axon not covered by myelin

Question 19

Axon terminals

Answer 19

End of neuron where axon branches off into other nerves, glands, or muscles

Question 20

synaptic cleft

Answer 20

Space between neuron or sensory cell and a neuron. Pre-synaptic cell and Post synaptic cell surround synapse.

Question 21

What are reflex arcs

Answer 21

• simple neural circuits controlled by spirnal cord (NOT BRAIN)

Question 22

Reflex arc pathway
(draw and label)

Answer 22

sensory neuron -> interneuron -> motor neuron
- Sensory cell is affected by stimulus
- release neurotransmitters to sensory neuron in PNS
- Action potential in sensory neuron
- NRTM go to interneuron in CNS
- CNS interprets impulse
- NRTM to to motor neuron in PNS
- motor neuron affect muscles and causes contraction

Question 23

draw and label a neuron diagram

Question 24

draw and label tree diagram of nervous systems