2.3 control and communication

Question 1

Where is the cerebrum located on the brain?

Answer 1

on the top

Question 2

Where is the medulla located on the brain?

Answer 2

in the middle / sticking out of the middle

Question 3

Where is the cerebellum located on the brain?

Answer 3

at the back

Question 4

What is the role of the cerebrum?

Answer 4

it enables conscious thought and memory

Question 5

What is the role of the cerebellum?

Answer 5

it controls co-ordination and balance

Question 6

What is the role of the medulla?

Answer 6

it controls heart rate and breathing rate

Question 7

What is the CNS made up of?

Answer 7

the brain and the spinal cord

Question 8

What is the function of the CNS?

Answer 8

Processing information from the senses and bring about appropriate responses. it allows communication between the cells of a multicellular organism.

Question 9

What is the stimulus?

Answer 9

it is a change in conditions that is detected by receptors

Question 10

what is the role of a sensory neurone?

Answer 10

passing information to the CNS in the form of electrical signals.

Question 11

What is the role of the motor neurone?

Answer 11

enabling a response to occur

Question 12

State the differences in responses brought about by the CNS.

Answer 12

some may be fast, like those from a muscle, and some may be slow, such as those from a gland.

Question 13

What are reflex reactions?

Answer 13

fast automatic responses which require no input from the brain

Question 14

Give 3 examples of reflex reactions

Answer 14

• coughing or sneezing
• choking
• blinking

Question 15

Why do we need reflex reactions?

Answer 15

They protect the body from harm as they are fast and produce fast reactions.

Question 16

Describe a reflex arc

Answer 16

The passage of an impulse from a sensory neurone, across an inter neurone to a motor neurone.

Question 17

How do electrical impulse move?

Answer 17

Along the neurone.

Question 18

What is a synapse?

Answer 18

a gap between neurones that allows chemicals to transfer from one neurone to another. it allows messages to be transferred to another neurone.

Question 19

What are hormones?

Answer 19

chemical messengers

Question 20

What do endocrine glands do?

Answer 20

release hormones into the blood stream where they travel to target tissues

Question 21

describe the structure of target tissues.

Answer 21

they have cells with special receptors for the hormone on their surface

Question 22

Why do hormones only affect their target tissue?

Answer 22

because only cells with the corresponding receptor will be affected by a specific hormone.

Question 23

What detects a change in blood glucose levels?

Answer 23

pancreas

Question 24

how can glucose be stored if glucose levels are too high?

Answer 24

as glycogen in the liver

Question 25

What happens when blood glucose levels increase?

Answer 25

the pancreas releases more insulin which travels to the liver where it activates enzymes in the liver cells to convert glucose to glycogen.

Question 26

What happens when blood glucose levels decrease?

Answer 26

the pancreas releases more glucagon which travels to the liver where it activates enzymes in the liver cells to convert glycogen into glucose.

Question 27

Describe type 1 diabetes

Answer 27

a disease caused by lack of insulin causing high blood glucose levels, treated by injecting insulin

Question 28

Describe type 2 diabetes

Answer 28

a disease caused by lack of response to insulin causing high blood glucose levels, treated by a good diet and exercise.

Question 29

Why is it important to control blood glucose levels?

Answer 29

if they are high they can cause damage to blood vessels and affect the functioning of the eyes and kidneys in particular.

Question 30

What can uncontrolled blood glucose levels cause problems with?

Answer 30

osmosis in cells