B10

Question 1

What is homeostasis ?

Answer 1

Regulation of internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes

Question 2

Why homeostasis is important?

Answer 2

Need the right conditions for enzymes actions. Enzymes have an optimum temperature

Question 3

What is an automatic control system?

Answer 3

Regulates internal environment , nervous system and hormonal system are examples

Question 4

What do automatic control systems regulate?

Answer 4

• blood glucose concentration
• body temperature
• water levels

Question 5

What is the response to na automatic control system?

Answer 5

Nervous responses or chemical responses

Question 6

What do receptors do?

Answer 6

Detect stimuli (changes in environment)

Question 7

What are coordination centres?

Answer 7

Recieve and process information from recoetors . These include the brain, spinal cord and pancreas

Question 8

What is the effector?

Answer 8

Muscles or glands which bring about responses which restore optimum levels

Question 9

What does the nervous system enable us to do?

Answer 9

React to surroundings and coordinate behaviour.

Question 10

Steps in the central nervous system ?

Answer 10

Stimulus
Receptor
Sensory neurone
CNS
Motor neurone
Effector
Response

Question 11

What is the central nervous system?

Answer 11

In vertebrates (animals with backbones) this consists of the brain , spinal cord only. Connected to the body by the sensory and motor neurones. It receives information from receptors and gives a response

Question 12

What is the sensory neurone?

Answer 12

Carry information as electrical impulses from the receptors to the cns?

Question 13

What carried electrical impulses?

Answer 13

Neurones

Question 14

What is the motor neurone.

Answer 14

Carries electrical impulse from the receptors to the cns

Question 15

Types of receptors?

Answer 15

• taste receptors in the tounge

- sound receptors in the ears.

Question 16

What are synapses?

Answer 16

Gaps between neurones

Question 17

What happens when an electrical impulse wnats to pass a synapse?

Answer 17

Transfere across by chemicals which diffuse across the gap . The chemicals then set of to the next electrical signal in the next neurone.

Question 18

What are reflex actions?

Answer 18

Automatic and rapid , they do not involve the conscious part of the brain. They can reduce the chance of being injured.

Question 19

Examples of a reflex action?

Answer 19

If someoje shines a bright light in your eye , your pupils get smaller to stop them from getting damaged. Or if you shock your body it releases adrenaline automatically

Question 20

What is the passage of information called in a reflex action?

Answer 20

Reflex arc

Question 21

How is a reflex arc different than a normal reaction?

Answer 21

Goes through the spine al cord or an unconscious part of the brain to make the reaction quicker.

Question 22

What are the chemicals called that diffuse across the synapse?

Answer 22

Neurotransmitter chemicals