nervous system and endocrine system

Question 1

define stimuli

Answer 1

changes in organism’s lifestyle

Question 2

define receptors

Answer 2

nerve endings on nerve cell that detect changes in internal and external environmenet

Question 3

define coordination

Answer 3

method which receptors pick up stimuli and pass information to effectors

Question 4

what is the importance of responding to stimuli

Answer 4

ensuring survival of organism
maintaining constant internal environment so that enzyme and cell can function efficiently

Question 5

what is the function of human nervous system

Answer 5

detect changes in external and internal environment
send nerve impulses to effectors to respond appropriately
coordinates function and activates inside body

Question 6

what is the use of myelin sheath

Answer 6

speed u[ transmission of impulses by allowing impulses to hop from one gap to another
acts as an insulator to prevent leakage of nerve impulses

Question 7

draw the 3 types of neuron

Answer 7

cell body
dendrites
axon
myelin sheath

Question 8

name the uses of each neuron

Answer 8

motor: receives information from integrating centre and send to effectors
sensory: detect stimuli via receptors and send info to integrating centre
interneuron: connect sensory neuron to motor neuron

Question 9

what is in CNS

Answer 9

brain and spinal cord
controls all activities

Question 10

what is in peripheral nervous system

Answer 10

cranial nerve & spinal nerve
controls sensory organ and effectors to CNS

Question 11

name the 3 parts of brain and their function

Answer 11

cerebrum: thinking, reasoning, speech
cerebellum : movement and balance
medulla : involuntary action

Question 12

function of spinal cord

Answer 12

controls reflex action
connect PNS to brain
contains cell bodies of neurons

Question 13

describe the process of transmission1 of info in nervous system

Answer 13

stimulus –> receptors –> sensory –> interneuron –> motor –> effector –> receptor

Question 14

describe how a synapse work

Answer 14

info reach pre synaptic cleft
synaptic vesicles release neurotransmitters into synaptic cleft
neurotransmitters diffuse across to post synaptic neuron
bind with receptors on postsynaptic membrane to fire electrical pulses

Question 15

what is the importance of synapse

Answer 15

enables neuron to hv a connection with other neuron
ensure impulses flow in one direction

Question 16

define the types of action

Answer 16

voluntary: conscious by cerebrum
involuntary: non conscious control which involves medulla or spinal cord

Question 17

define a reflex action

Answer 17

fast automatic response to stimulus
involves spinal cord as integrating centre

Question 18

label the eye and their function

Answer 18

sclera- protect eye
retina - contains light sensitive receptors
cornea - refracts light
iris- controls how much light enters pupil
lens- focus light onto retina
optic nerve - carries impulses to brain
fovea

Question 19

what is rod cells

Answer 19

sensitive to low light intensity
detects grey
around retina

Question 20

what is cone cells

Answer 20

detects colour
in fovea and retina

Question 21

describe what happens when we see far objects

Answer 21

CCC
ciliary muscle relax
suspensory ligament taut
eye lens become thin

Question 22

what happens to eye in bright light

Answer 22

radial muscle relax
circular muscle contract
pupil constrict

Question 23

define a hormone

Answer 23

chemical messenger produced by endocrine glands

Question 24

define endocrine glands

Answer 24

ductless glands that release and produce hormones into bloodstream

Question 25

define target cells

Answer 25

specific cells affected by hormones

Question 26

what is the function of hormones

Answer 26

regulated activities in tissues and organs

Question 27

describe how hormones work

Answer 27

hormone enters blood stream
goes into target cells
binds with receptors on plasma membrane
cell response in specific manner