Nat5 Biology Unit 2 Multicellular Organisms Key Area 2 Control and Communications

Question 1

What an be a response to a stimulus?

Answer 1

A rapid action from a muscle or a slower response from a gland

Question 2

The nervous system consists of…

Answer 2

The Central Nervous System (CNS) and other nerves

Question 3

What are three structures of the brain?

Answer 3

Cerebrum
Cerebellum
Medulla

Question 4

What does the Cerebrum do?

Cerebral hemispheres

Answer 4

Controls language, memory, personality and conscious thought

Question 5

What does the Medulla do?

Answer 5

Controls heart rate and breathing rate

Question 6

What does the Cerebellum do?

Answer 6

Controls balance and co-ordination of movement

Question 7

What are the three neuron types?

Answer 7

Sensory
Inter
Motor

Question 8

What do Sensory neurons do?

Answer 8

Pass information to the CNS

Question 9

What do Inter neurons do?

Answer 9

Operate within the CNS,which processes information from the senses that require a response

Question 10

What do Motor neurons do?

Answer 10

Carry impulses from the CNS to the effectors (muscle or gland)

Question 11

What are the three parts of a neuron?

Answer 11

A cell body containing cytoplasm and a nucleus the cell bodies are locate in the brain and spinal cord
Fibers which carry impulses into the cell bodies
Fibers carrying impulses away from the cell bodies

Question 12

What are the four things a reflex action is? (PAIR)

Answer 12

Protective
Automatic
Involuntary (cannot be ignored and not under conscious control)
Rapid

Question 13

What do receptors do?

Answer 13

Detect sensory input/stimuli

Question 14

Electrical impulses… Chemical impulses transfer these messages between…

Answer 14

Carry messages along neurons

Neurons at synapses

Question 15

What do reflexes do?

Answer 15

Protect the body from harm.

They do NOT prevent harm from happening

Question 16

What is a synapse?

Answer 16

A gap between adjoining neurons. Nerves impulses arriving at a synapse causes diffusion of a chemical substance (neurotransmitter) which crosses the gap and triggered off nerve impulses in the next neuron.

Question 17

What is a reflex arc

Answer 17

The structures involved and the nerve impulses responsible fore reflex actions make up what is called a reflex arc

Question 18

What do endocrine glands do?

Answer 18

Release hormones into the bloodstream

Question 19

Hormones are…

Answer 19

Chemical messengers

Question 20

A target tissue has cells with…

Answer 20

Complementary receptor proteins for specific hormones, so only that tissue will be affected by these hormones

Question 21

What does the pancreas do?

Answer 21

Regulates glucose levels in the blood

Question 23

What is Insulin? Where is it Produced? What’s it’s Target organ? What is it’s effect?

Answer 23

A hormone produced in the pancreas, it’s target organ is the liver. It triggers the production of enzymes which converts glucose to glycogen

Question 24

What is Glucagon? Where is it Produced? What’s it’s Target organ? What is it’s effect?

Answer 24

A hormone produced in the pancreas, it’s target organ is the liver. It triggers the production of enzymes which converts glycogen to glucose

Question 25

What thing happens when the glucose concentration gets too high?

Answer 25

The pancreas secretes more insulin into the blood. The liver converts glucose to glycogen for storage in the liver so the blood glucose level goes down

Question 26

What thing happens when the blood glucose concentration is too low?

Answer 26

The pancreas secretes glucagon into the blood, so the liver converts the stored glycogen into glucose so the blood glucose level goes up

Question 27

What happens when a reflex arc is set up?

Answer 27

When an environmental stimulus triggers a nerve impulse at a RECEPTOR. This impulse is transmitted along a SENSORY NEURON to the spinal cord, where it crosses a SYNAPSE to an INTER NEURON. The impulse passes across another SYNAPSE to a MOTOR NEURON which then transmits it to an effector, usually a muscle