Chapter 11 -Nervous System

Front 1

Homeostasis?

Back 1

A state of relative stability within the body

Front 2

What does the CNS consist of? Purpose?

Back 2

Consists of Brain and Spinal Cord.

Brain intergrates and processes information from PNS.

Hint 2

CNS= Central Nervous System

Front 3

What pathways does the PNS have? Importance of each?

Back 3

Consists of sensory pathways and motor pathways.

Sensory pathways (afferent) carries info (from senses) to CNS

Motor pathways (efferent) relays info from CNS to muscles/glands

Hint 3

PNS= Peripheral Nervous System

Front 4

What are Motor pathways broken down into?

Back 4

Under the Somatic (under voluntary control) and Automatic (involuntary control) Nervous System.

Front 5

What are 2 kinds of Automatic Nervous System?

Back 5

Sympathetic (stress response; fight or flight) and Parasympathetic (relaxing; rest and digest)

Front 6

What are neurons? What do they do?

Back 6

Basic structural and functional units of the nervous system.

They respond to stimuli and conduct electrochemical signals (impulses).

Front 7

Three types of neurons?

Back 7

Sensory neurons, interneurons, and motor neurons.

Front 8

Sensory neurons' purpose?

Back 8

Gather info from senses and transmit impulses to CNS

Front 9

Interneurons purpose?

Back 9

Process and intergrate incoming info and relay out going info.

Hint 9

Found everywhere in CNS, link between sensory and motor neurons

Front 10

Motor Neurons purpose?

Back 10

Transmit info from CNS to muscles, glands and other organs.

Front 11

Reflex Arc?

Back 11

Allow body to react quickly (few neurons), before you're consciously aware of threat.

Move directly to and from CNS before brain process information.

Hint 11

(React, then feel pain)

Front 12

What is Dendrite? Info flow?

Back 12

The extension of the neuron that gets info from receptors.

They conduct impulses towards the cell body.

Hint 12

In the case of sensory and motor neurons

Front 13

What is cell body?

Back 13

They process info/input from the dendrite. Relays info to axon where impulses are initiated.

Hint 13

Contains the nucleus.

Front 14

What is axon?

Back 14

Carries an impulse towards others neurons/an effector (muscle).

Hint 14

Takes info away from cell body.

Front 15

What is axon terminal/bulb?

Back 15

They release chemicals (neurotransmitters) to communicate with other neurons, muscles or glands

Hint 15

End of axon that branches into many fibres.

Front 16

Myelin Sheath? Purpose? Formed by?

Back 16

Formed by Schwann cells.

Provides protection to neuron, and speeds up impulse transmission.

Hint 16

Most neurons in PNS are myelinated.

Front 17

Unmyelinated axon? Function?

Back 17

Means that they are without myelin Sheath. The impulses travel slower, since action potential happens all the way to axon.

Front 18

Myelinated axon?

Back 18

Axon protected by myelin Sheath, and action potential only happens at the node of Ranvier. TRAVELS FASTER.

Front 19

White matter? (In CNS)

Back 19

Myelinated neurons

Front 20

Grey matter? (In CNS)

Back 20

Unmyelinated neurons

Front 21

What happens is there are no impulses travelling along neuron?

Back 21

There's no separation of charges (polarized) across the membrane

Hint 21

The neuron is at rest.

Front 22

What is the difference between the inside and outside membrane charges?

Back 22

Inside is negative compared to outside

Front 23

What is the biggest contributor to polarization?

Back 23

Sodium/Potassium Exchange Pump

Front 24

What does the Na+/K+ pump do?

Back 24

They use ATP to transport Na+ ions out and K+ ions into the axon (across the membrane)

Hint 24

Hint: Active Transport

Front 25

What is ration of the pump of things going in and out?

Back 25

3 Na+ ions out and 2 K+ ions in

Front 26

Which side is more positive?

Back 26

The outside of membrane

Front 27

sodium/potassium channel/gates allow? Flow of Na+ and K+ when gates open?

Back 27

allows the diffusion of ions.

When the gates open, (Na+/K+) will move down their concentration gradients

Front 28

Passive Transport? Examples?

Back 28

Means no ATP/energy is needed.

Ex: osmosis, diffusion

Front 29

What happens during the axon's passive Transport?

Back 29

Na+ ions move into the axon

K+ ions move out of the axon

Side: gates open/close at different rates

Front 30

What does polarized mean?

Back 30

That membrane is at rest, and that no stimulus is sent yet.

Front 31

Do pumps work when gates closed?

Back 31

Yes

Front 32

Answer in sequential order:

Outside of axon is _______, inside of axon is __________.

Back 32

positive, negative

Front 33

What happens in Na+/K+ pump in a depolarized axon?

Back 33

Na+ channels/gates open, as Na+ rush into the axon.

K+ gates stay closed, hence K+ ions stay inside the axon.

Hint 33

When Na+ and K+ flow out, they follow their [] gradients

Front 34

How's the charge in a depolarized axon? Why?

Back 34

Ionic charge be around 30-40+ mV

Because Na+ is moving into axon and K+ stays inside

Hint 34

Depolarized- negative to positive

Front 35

What happens during Repolarization? (in the pump)

Back 35

Na+ gates close and K+ gates open.

K+ ions leave axon to follow [] gradient, and Na+ stops flowing into axon.

Front 36

What happens to the charge in repolarization?

Back 36

Ionic charge in axon goes to -90mV

This is hyperpolarization.

Hint 36

Think, positive to negative, and hyper-too much

Front 37

What happens after repolarization? Describe pump activity.

Back 37

Na+/K+ pumps re-establish resting membrane potential of -70mV, since both gates are closed.

Front 38

Purpose of refractionary period?

Back 38

Prevents impulse from going backwards and action potential from happening again at the same location.

Front 39

What is refractionary period?

(not part of notes)

Back 39

This is the time during which another stimulus given to the neuron (no matter how strong) will not lead to a second action potential.

Front 40

What is threshold potential?

Back 40

the minimum amount of stimulus needed to produce an action potential

usually -55mV

Front 41

what happens when -55 mV is not reached in axon?

Back 41

an impulse will not be initiated (no action potential)

Front 42

What is intensity determined by?

Back 42

the number of impulses;

they create a stronger action potential

Front 43

Will depolarization between -70 mV and -55mV cause an action potential?

Back 43

No

Front 44

Will depolarization greater than -55mV produce action potentials?

Back 44

Yes, and they'll be identical

Front 45

What is the blood-brain barrier?

Back 45

Separation of the blood and the central nervous system.

Front 46

Frontal Lobe of Brain function and location?

Back 46

At front of the cerebrum

Involved with conscious thought. Where information is integrated from other brain parts controlling reasoning, memory, personality, intelligence. Controls involuntary muscle movements.

Front 47

Temporal Lobe function and location?

Back 47

Located Below frontal lobe.

Main function is auditory reception, though they also process visual info, and is linked to retrieving visual and verbal memories.

Front 48

Parietal Lobe function?

Back 48

Receive and process sensory info from skin. Also helps to process info body's position and orientation.

Front 49

Occipital Lobe?

Back 49

Receives and processes visual info, and helps person recognize objects/things witnessed.

Front 50

Cerecellum: Location and main function.

Back 50

Is in hindbrain, and controls muscle coordination and balance

Front 51

Medulla Oblongata: location and main function

Back 51

In hindbrain, controls all the subconscious activities such as breathing, vomiting, blood pressure, swallowing, heart rate etc

Front 52

Pons: function and location

Back 52

At the hindbrain, and job is to relay info between cerebellum and cerebral cortex

Front 53

Midbrain function?

Back 53

to get sensory input, connecting hindbrain to forebrain

Front 54

Thalamus location and function?

Back 54

is at forebrain, and relays info from senses. also connects various brain parts

Front 55

Hypothalamus location and function?

Back 55

at forebrain.

regulates pituitary gland, heart rate, blood pressure, temp, and controls drives such as hunger, thirst, and sexual desire

Front 56

Corpus Callosum function and location?

Back 56

Is in cerebrum, and connects the left/right cerebral hemispheres through nerve tracts

Front 57

Cerebrum controls what?

Back 57

Containing the 4 lobes, and ability to speak clear

Front 58

Cerebellum controls?

Back 58

sensory/motor- helps the person walk straight