The Nervous system

Question 1

Define neuron

Answer 1

a single nerve cell

Question 2

function of a sensory neuron

Answer 2

carry electrical messages (ion) from the peripheral nervous system to the CNS

Question 3

function of a motor neuron

Answer 3

carry electrical messages away from the CNS to the peripheral nervous system

Question 4

function of an interneuron

Answer 4

converts sensory messages to motor messages in the brain/spinal cord

Question 5

Neurotransmitter

Answer 5

a chemical produced by the synaptic knob that carry an electrical impluse across the synaptic cleft to the next neuron

Question 6

reflex action

Answer 6

immediate,involuntary and automatic response to a stimulus not under consious control

Question 7

reflex arc

Answer 7

pathway taken by a reflex action through the spinal cord

Question 8

grey matter

Answer 8

rich in cell bodies

Question 9

white matter

Answer 9

rich in axons

Question 10

where is the CNS

Answer 10

brain and spinal cord

Question 11

Peripheral nervous system

Answer 11

all nerves that feed into the CNS

Question 12

Enzymes

Answer 12

biological catalyst

Question 13

What is the nervous system composed of

Answer 13

Central Nervous System- brain + spinal cord.
Peripheral Nervous-all other nerves in body

Question 14

What do nerves do

Answer 14

carry messages around the body in the form of electrical messages called ions.Nerves are made up of nerve cells called neurons

Question 15

What are the three types of neurons

Answer 15

sensory neuron, motor neuron,interneuron

Question 16

Dendrite

Answer 16

located @ one end of the neuron, picks up electrical impluses from axon of previous cell

Question 17

cell body

Answer 17

contains a nucleus and controls the activities of the neuron

Question 18

schwann cells

Answer 18

produce myelin sheath. these cells form a protective layer

Question 19

myelin sheath

Answer 19

fat rich layer that acts as a insulator and speeds up rate of transmission of electrical impluse

Question 20

receptor

Answer 20

group of cells that detect a stimlus

Question 21

axon

Answer 21

carries electrical impluse along a nerve

Question 22

synaptic knob

Answer 22

found at end of axon, produces neurotransmitter

Question 23

synaptic cleft

Answer 23

gap between axon of one neuron and dendrite of another neuron

Question 24

synapse

Answer 24

region including axon of one neuro and dendrite of another neuron

Question 25

neurotransmitter

Answer 25

chemical produced to carry electrical impluse across a synptic cleft (eg dopamine)

Question 26

threshold

Answer 26

minium stimulus needed to cause an impluse to be carried in a neuron

Question 27

breifly describe the all of nothing

Answer 27

if a stimulus is not enough, there is no impluse crried. If there is enough stimulus the impluse is carried and changes its permibility to ions. It causes the postive charge to move

Question 28

what is the speed of impluse dertimined by

Answer 28

presence or absence of myelin sheath

Question 29

How is nerve impluse transmitted across synptic cleft

Answer 29

electrical impluses arrives at synaptic knob. synaptic knob produces neurotransmitter that diffuses across the synaptic cleft. combined with receptors on postsynaptic neuron. neurotransmitter broken down by enxymes and reabsorbed by presynaptic neuron.

Question 30

functions of synpses

Answer 30

transmit impluses from neuron to neuron or an effector. control direction of the impluse, they allow only one way flow. the prevent the overstimulation of effectors.

Question 31

central canal

Answer 31

contins cerebrospinal fluid

Question 32

Dorsal root

Answer 32

carries sensory neurons

Question 33

ventral root

Answer 33

carries motor neurons

Question 34

ganglia

Answer 34

carries groups of cell bodies

Question 35

Name a deficiency disease associated with the nervous system stating a. Cause b. Symptoms c. Treatment d. Prevention

Answer 35

Parkinsons disease a.failure to produce dopamine b.hand tremors,ridgid muscles,loss of sutomatic movements. c.physiothreapy, special aids, medication that mimics/ produces dopamine. d. no prevention

Question 36

what is reflex action

Answer 36

Immediate, involuntary and automatic response of the body to a stimulus not under conscious control

Question 37

describe the mechanism of relfex action

Answer 37

receptors detect harm. impluse carried to spinal cord via sensory neuron and through dorsal root.The sensory neuron synpses with other neurons. impluse converted into motor neuron via interneuron, it is passed on to motor neuron via ventral root. muscle recieves the impluse ***Note: relfex actions can be inhibited***

Question 38

differences between nerves and horomones

Answer 38

**Nerves** electrical messages fast travelling short lasting effect on target area specific target area immediate response time **Horomones** Chemical messages slow travelling long lasting effect on target area general target area slow response time

Question 39

What is the front brain called

Answer 39

forebrain

Question 40

what is the back brain called

Answer 40

hindbrain

Question 41

list the layers of the head and its purposes

Answer 41

Skull, cerebofluid,meniges membrane

Question 42

Name the functions of the cerebrum

Answer 42

its the largest part of brain. voluntary movement, memory,thinking, intelligence

Question 43

Name the functions of the hypothalamus

Answer 43

regulate homeostasis ( maintains a constant interal enviorment in the body inc body temp, thirst

Question 44

Name the functions of the pituatary gland

Answer 44

produces TSH, GH(Growth horomone), FHS (Follicle stimulating horomone)

Question 45

Name the functions of the Cerebellum

Answer 45

corrdinates movement, balance, hand-eye coordination

Question 46

Name the functions of the Medulla oblongata

Answer 46

contains invlountary movement including breathing, heartrate and swallowing.

Question 47

Name the functions of the thalamus

Answer 47

sends messages to different parts of the brain