grey matter

Question 1

what is the central nervous system made up of

Answer 1

brain
spinal cord

Question 2

what is the largest part of the brain

Answer 2

cerebrum

Question 3

what are the functions of the cerebrum

Answer 3

vision
hearing
speech
thinking
memory

Question 4

what are the 2 halves of the cerebrum

Answer 4

cerebral hemispheres
joined by a band of nerve fibres called the corpus callosum
right hemisphere controls left side of body and vice versa

Question 5

what is the thin outer layer of the cerebrum

Answer 5

cerebral cortex/ grey matter
consists of cell bodies of neurones
highly folded
increases sa
so more neurones
more neurone connections
more ability of brain to carry out complex behaviours

Question 6

what is beneath the cerebral cortex/ grey matter

Answer 6

white matter
consists of myelinated axons of neurones

Question 7

what are the functions of the hypothalamus

Answer 7

monitors blood as it flows to the brain
releases hormones/ stimulates pituitary gland to do so

regulates body temp by monitoring blood temp

osmoregulation
water balance of blood
release ADH if blood too conc
AGH increases water absorption in kidneys

regulates digestive activity
hormones that control appetite
secretion of digestive enzymes

endocrine functions
metabolism, puberty

Question 8

what are the functions of the cerebellum

Answer 8

coordinates movement
including balance which involves coordination between eyes, muscles, semicircular canals in ears

Question 9

what are the functions of the medulla oblongata aka medulla

Answer 9

contains coordination centres that control diff functions
cardiac centre- heart rate
respiratory centre- breathing rate

Question 10

what are neurones

Answer 10

specialised cells of the nervous system which carry electrical impulses around the body

Question 11

what is a nerve

Answer 11

a bundle of neurones

Question 12

what features are in all neurones

Answer 12

axon
cell body
axon terminal

Question 13

what is an axon terminal

Answer 13

has many nerve endings
allows neurones to connect and receive impulses from others

Question 14

what is a myelin sheath

Answer 14

insulates axon in myelinated cells

made of Schwann cells

uninsulated gaps between Schwann cells called nodes of Ranvier

Question 15

why do myelinated cells have faster impulse transmissions

Answer 15

electron impulses dont travel down whole axon

jump from one node to the next

in non myelinated cells, impulse travels slower cos moves down entire length of axon

Question 16

function of sensory neurone

Answer 16

carry electrical impulses from receptors to CNS

Question 17

function of relay neurone

Answer 17

found entirely within CNS
connect sensory and motor

Question 18

function of motor neurone

Answer 18

carry impulses from CNS to effector muscles or glands

Question 19

structure of motor neurone

Answer 19

large cell body at one end in spinal cord/ brain
many highly branched dendrites extending from it

Question 20

structure of sensory neurone

Answer 20

cell body that branches off in middle of axon
dendrites attached to a receptor cell

Question 21

what is a stimulus

Answer 21

a change in the environment

Question 22

what does a receptor do

Answer 22

detect stimuli

Question 23

what are effectors

Answer 23

muscles or glands
that bring about a response

Question 24

what is the pathway that nerve impulses pass along the nervous system

Answer 24

stimulus
receptor
sensory neurone
CNS
motor neurone
effector

Question 25

what is the pathway that nerve impulses pass along the nervous system along when there is bright light

Answer 25

light receptors in eyes
sensory neurone
CNS
motor neurone
circular muscles in iris

Question 26

what does contraction of circular muscles cause

Answer 26

pupils to constrict
limits amt of light entering eye
prevents damage to retina

Question 27

what is the pathway that nerve impulses pass along the nervous system along when there is low light

Answer 27

light receptors in eyes
sensory neurone
CNS
motor neurone
radial muscles in iris

Question 28

what does contraction of radial muscles cause

Answer 28

pupil to dilate
maximises amt of light entering eye
improving vision