The nervous system and the endocrine system

Question 1

The nervous system

functions

Answer 1

• to collect, process and respond to information in the environment
• to co-ordinate the working of different organs and cells in the body

Question 2

The nervous system

parts

Answer 2

The central nervous system (SNS)
└brain, spinal cord
The peripheral nervous system (PNS)
└somatic nervous system, automatic nervous system (sympathetic/parasympathetic nervous system)

Question 3

The central nervous system (SNS)

function

Answer 3

└is the origin of all complex commands and decisions
└passes messages to and from the brain
└connects nerves to PNS

Question 4

The central nervous system (SNS)

parts

Answer 4

Brain

Spinal cord

Question 5

Brain

function

Answer 5

└the centre of all conscious awareness
└humans have highly developed cerebral cortex= complex
└brain is divided into two hemispheres

Question 6

Spinal cord

function

Answer 6

└an extension of the brain
└responsible for reflex actions
└e.g. hand away from heat

Question 7

The peripheral nervous system (PNS)

function

Answer 7

• sends information to the CNS from the external environment

- transmits messages from the CNS to muscles and glands in the body

Question 8

The peripheral nervous system (PNS)

parts

Answer 8

Somatic nervous system
Autonomic nervous system (ANS)
└sympathetic/parasympathetic nervous system

Question 9

Somatic nervous system

function

Answer 9

└transmits information from receptor cells in the sense organs toe the CNS
└receives information from the CNS that directs muscles to act
└controls muscle movement
└receives information from sensory receptors

Question 10

The peripheral nervous system (PNS)

function

Answer 10

└transmits information to and from internal body organs
└autonomic as the system operates involuntarily (is automatic)
└controls functions such as breathing, heart rate, digestion and stress responses

Question 11

The peripheral nervous system (PNS)

parts

Answer 11

└sympathetic nervous system

└parasympathetic nervous system

Question 12

Sympathetic state

Answer 12

└increases heart rate
└increases breathing rate
└dilates pupils
└ inhibits digestion
└inhibits saliva production

Question 13

Parasympathetic state

Answer 13

└decreases heart rate
└decreases breathing rate
└constricts pupils
└stimulates digestion
└stimulates saliva production

Question 14

The endocrine system

parts

Answer 14

Glands and hormones

Endocrine and ANS working together: Fight or flight

Question 15

gland

definition

Answer 15

an organ in the body that synthesises substances such as hormones

Question 16

gland

example

Answer 16

• adrenal gland: adrenalline (fight or flight)

- pancreas- insulin/glucagon (blood sugar levels)

Question 17

hormones

definition

Answer 17

-chemical substances that circulate in the bloodstream and only affect target organs
└produced in large quantities but disappear quickly
└powerful effects

Question 18

endocrine system

definition

Answer 18

one of the bodies main information systems

Question 19

endocrine system

function

Answer 19

└instructs glands to release hormones directly into the bloodstream
└hormones carried towards target organs in the body
└endocrine system acts more slowly than the nervous system

Question 20

fight or flight response

definition

Answer 20

the way an animal responds when stressed

└the body becomes physiologically aroused in readiness to fight or flee

Question 21

Adrenaline

Answer 21

a hormone produced by the adrenal glands (part of the bodies immediate stress response system)
└strong effect on cells of the cardiovascular system
└stimulates heart rate, contracts blood vessels, dilates air passages

Question 22

How endocrine and nervous system work together e.g. in stressful event

Answer 22

stressor perceived → hypothalamus triggers activity in sympathetic branch of the ANS. ANS changes from normal resting state (parasympathetic state)→physiologically aroused sympathetic state. Stress hormone adrenaline released from the adrenal medulla into the bloodstream→creates physiological arousal necessary for fight or flight response

└automatic response
└once threat has passes, parasympathetic nervous system returns to normal resting state
└antagonistic to sympathetic system (aka the rest and digest response)