Homeostasis

Question 1

Homeostasis

Answer 1

The regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and eternal changes

Question 2

What does homeostasis regulate?

Answer 2

• Blood glucose concentration
• Body temperature
• Water levels

Question 3

What are receptors?

Answer 3

Detect stimuli

Question 4

What are coordination centres?

Answer 4

Receive and process information from receptors

• Brain
• Spinal cord
• Pancreas

Question 5

What are effectors?

Answer 5

Muscles or glands which bring about responses to react to environment (restore optimum levels)

Question 6

What is the central nervous system?

Answer 6

BRAIN and SPINAL CORD

Question 7

What is the peripheral nervous system?

Answer 7

ALL the NERVES in your body

Question 8

What does the nervous system do?

Answer 8

Allows humans to REACT to their surroundings and to COORDINATE behaviour

Question 9

How is information sent through the nervous system?

Answer 9

Through ELECTRICAL IMPULSES that pass along nerve cells called NEURONES

Question 10

What is a nerve?

Answer 10

A bundle of neurones

Question 11

What is the actual function of the CNS?

Answer 11

CNS coordinates the response of receptors

Question 12

What are neurones made up of?

Answer 12

• A cell body (nucleus and main organelles are found here)

- Cytoplasmic extensions from this body called AXONS and DENDRITES

Question 13

What is adaptation of a neuron?

Answer 13

• Some human neurones are 1m long
• Much more effective than having multiple neurons which wastes time transferring electrical impulses from one cell to another

Question 14

What is an adaptation of the axon?

Answer 14

Fatty sheath acts as an insulator

Question 15

What is the path of response in the nervous system?

Answer 15

Stimulus, receptor, coordinator, effector, response

Question 16

What is a reflex?

Answer 16

An involuntary, rapid action which does not involve the conscious part of the brain

Question 17

What does the reflex arc involve?

Answer 17

1. Stimulus
2. A sensory neurone sends electrical impulses to the spinal cord (COORDINATOR)
3. An electrical impulse is passed to a RELAY NEURONE in the spinal cord
4. Relay neurone synapses with a motor neurone
5. A motor neurone carries an impulse to a muscle (THE EFFECTOR)
6. The muscle pulls the body part away from the dangerous stimulus

Question 18

What is the sensory neurone?

Answer 18

Carry impulses from sense organs to CNS (brain or spinal cord)

Question 19

What is the relay neurone?

Answer 19

Found inside the CNS and connect SENSORY and MOTOR neurones

Question 20

What are motor neurones?

Answer 20

Carry impulses from the CNS to the effectors (muscles) where the action is carried out

Question 21

What is the brain

Answer 21

• Part of the central nervous system
• Made of billions of interconnected neurones
• Responsible for controlling complex behaviours

Question 22

Where is the cerebral cortex

Answer 22

Front of brain

Question 23

Where is the cerebellum?

Answer 23

Back of brain (bottom)

Question 24

Where is the medulla?

Answer 24

Bottom, connecting to spinal cord

Question 25

What does the Cerebral cortex control?

Answer 25

Responsible for

• Intelligence
• Memory
• Consciousness
• Personality

Question 26

What does the Cerebellum control?

Answer 26

Responsible for

• Balance
• Muscle coordination
• Movement

Question 27

What does the medulla control?

Answer 27

Responsible for

• Unconscious activities
• Such as heart rate or breathing

Question 28

Why is it so difficult to study the brain?

Answer 28

• Very delicate
• High risk of damage if studying a living brain
• Accidents could lead to speech or motor issues