the nervous system

Question 1

central nervous system (CNS)

Answer 1

brain and spinal cord

Question 2

peripheral nervous system

Answer 2

twelve cranial nerve pairs and 31 spinal nerve pairs

Question 3

autonomic system

Answer 3

controlling all functions necessary for life

Question 4

somatic system

Answer 4

all functions that are non-essential for life

Question 5

sympathetic system

Answer 5

‘fight or flight response’

Question 6

parasympathetic system

Answer 6

returns the body to normal

Question 7

general functions of the nervous system

Answer 7

• gather information about internal and external environments
• transmit that information to the CNS
• process that information
• determine a response to that information
• transmit instructions to effector organs

Question 8

‘fight or flight’ response

Answer 8

a reaction to a potentially dangerous situation. danger does not have to be real to be perceived as such. most of the effects are caused by the release of adrenaline from the adrenal glands.

Question 9

effects of adrenaline

Answer 9

dilated pupils, decrease in production of slaiva, increased heart rate, dilated bronchioles, inhibits peristalsis, restricts blood flow to digestive system, decreases egestion of digestive enzymes, increases blood flow to muscles, relaxes the bladder valve ans stimulates the conversion of glycogen to glucose.

Question 10

purpose of adrenaline responses

Answer 10

all of these responses are designed to increase visual acquity, provide sufficient oxygen t increase muscle function and reduce energy wastage and non-essential processes

Question 11

double innervation

Answer 11

if left uncontrolled, the sympathetic nervous system can result in death. the parasympathetic nervous system is responsible for returning the body to a normal state, reversing all of these effects. this is a negative feedback system.

Question 12

afferent nerves

Answer 12

moving towards the brain (taking in)

Question 13

efferent nerves

Answer 13

exiting or leaving the brain

Question 14

vital reflexes controlled by the medulla oblongata

Answer 14

# Respiratory centre - breathing rate and depth
# Vasomotor centre - controls blood pressure and body
# Cardio-motor centre - rate of the heart beat
# Visceral activities

Question 15

non-vital reflexes controlled by the medulla oblongata

Answer 15

• salivation
• coughing
• blinking
• hiccoughing
• sneezing

Question 16

white matter vs grey matter

Answer 16

fat is present in white matter and absent in grey matter. as white and grey matter pass through the medulla oblongata, they switch places.

Question 17

function of the spinal cord

Answer 17

to connect sensory organs (receptors) to the brain

Question 18

immediate reflex actions

Answer 18

majority of immediate reflex actions travel to the spinal cord before the brain to increase reflex speed to save time and possibly save your life

Question 19

effectors

Answer 19

muscles and glands that cause an effect

Question 20

four main functions of the spinal cord

Answer 20

1 Works with m. oblongata to control reflex actions which are independent of the brain.
2 Afferent impulses are conducted up from receptors via the cord, to the brain.
3 Efferent impulses are conducted are conducted down from the brain, via the cord, to the effector muscles.
4 Sympathetic nerve impulses and some of the para-sympathetic nerve impulses are connected via the spinal nerves to the spinal cord.

Question 21

sensory neurons

Answer 21

• receive information and conduct impulses from muscles or glands throughout the body to the spinal cord and brain
• afferent neurons
• cell body has only one or two outgrowths - a dendrite and an axon
• monopolar and bipolar neurons

Question 22

motor neurons

Answer 22

• receive information and conduct impulses from the spinal cord and brain to muscles or glands throughout the body
• Efferent neurons
• Cell body has many outgrowths - dendrites and an axon
• Are multipolar neurons

Question 23

reflex arc definition

Answer 23

the structure/pathway along which electrical signals travel to generate a reflex action

Question 24

reflex action definition

Answer 24

a seemingly instantaneous response to any situation that is either life-threatening or potentially harmful