Approaches

Question 1

• NERVOUS SYSTEM TWO MAIN FUNCTIONS=

Answer 1

• 1. to collect, process and respond to info in environment
• 2. To co coordinate the working of all different organs and cells in the body

Question 2

SIMALTANEOUS ACTION

Answer 2

• 1. stressor perceived
• 2. Hypothalamus a rival pituitary gland
• 3. ANS= sympathetic to parasympathetic
• 4. Adrenaline secreted from adrenal medulla- physiological arousal necessary for fight or flight
• 5. IMMEDIATE, ACUTE AND AUTOMATIC
• Once threat passed, parasympathetic acts as a brake and reduces activities of body increased by sympathetic. Antagonistic action

Question 3

STRUCTURE OF NERVE CELL

Answer 3

• dendrites= carry nerve impulses from neighbouring neurones towards the cell body
• Axon= away from cell body down neurone
• Nodes of ranvier= speed up transmission by driving electrical signal to jump across gaps along the axon
• terminal buttons= communicate with the next neurone in the chain across the gap of a synapse

Question 4

LOCATION OF NEURONES

Answer 4

• MOTOR= CNS and PNS
• SENSORY= in PNS in clusters (ganglia)
• RELAY= 97% of all neurones, brain and visual system

Question 5

FIRING OF NEURONE

Answer 5

• action potential occurs when positively charged for split second
• Creates an electrical impulse

Question 6

CHEMICAL TRANSMISSION

Answer 6

• neurones communicate in groups= NEURAL NETWORKS

Question 7

ONE TO THE NEXT

Answer 7

• 1. end of prestnaptic to prestnaptic terminal
• 2. Synaptic vesicles are triggered to release neurotransmitters
• 3. Travel across synapse
• 4. Taken up by postsynaptic receptor site on dendrite of next
• 5. Back to electrical impulse
• One way system( rel by pre, taken by post)
• NEUROTRANSMITTERS COMPLIMENTARY SPECIFIC SHAPES TO POSTSYNAPTIC NEURONE RECEPTOR SITE
• Specialist functions= ACh causes muscle contraction where muscle meets motor neurone

Question 8

EXITATION VS INHIBITION

Answer 8

• one or the other
• Ex= more positive, more likely to fire ie adrenaline
• In= more negative, less likely ie serotonin

Question 9

SUMMATION

Answer 9

• excitatory and inhibitory influences summed
• Net effect determines action of neurone
• Action potential of postsynaptic neurone only triggered when sum of un and ex signals at any one time reaches threshold