Unit 5

Question 1

Why are homeostatic control systems important in the body?

Answer 1

They maintain the right conditions for cells to function

Question 2

Which part of the nervous system do the brain and spinal cord form

Answer 2

CNS

Question 3

What’s the function of the nervous system in humans

Answer 3

It allows them to react to their surroundings and co-ordinate their behaviour

Question 4

Name two types of effector and state how they respond to nervous impulses

Answer 4

Muscles can contract

Glands can secrete hormones

Question 5

What are the three types of neurones

Answer 5

Sensory neurones, motor neurones, relay neurones

Question 6

How is a signal transmitted across a synapse

Answer 6

Chemicals diffuse across a gap and transfer the nerve signal

Question 7

Name the type of cell that makes up most of the brain’s material

Answer 7

Neurones

Question 8

State two activities that take place in the human body which are unconscious

Answer 8

Respiration

Heart rate

Question 9

Why is it difficult to investigate and treat brain disorders

Answer 9

It is very complex and very fragile

Question 10

Which two parts of the eye change shape during focusing

Answer 10

Suspensory ligaments

Cillary muscles

Question 11

Why is it important to the pupil to change size

Answer 11

So that the amount of light entering can be controlled so that bright light cannot damage the retina and to allow sufficient light to enter the item condition

Question 12

What is the process of accommodation?

Answer 12

Focusing light on the retina by changing the shape of the lens

Question 13

How does the eye work to focus on a near object

Answer 13

The ciliary muscles contract and the suspensory ligament slacken
The lens becomes more curved
The lens refracts light rays strongly

Question 14

How does the eye work to focus on a distant object

Answer 14

The ciliary muscles contract and the suspensory ligaments are pulled tight
This means that the lens becomes less curved
Therefore less light is refracted

Question 15

Explain how a spectacle lens correct the sight of a person with a vision defect

Answer 15

The lens refract light rays so they focus on the retina

Question 16

What does a concave lens look like

Answer 16

a sand timer

Question 17

What is a convex lens looks like

Answer 17

And eye

Question 18

How can you laser technology correct vision defects

Answer 18

It changes the shape of the cornea to change how strongly light is refracted into the eye

Question 19

Suggest the risk of replacement lens surgery

Answer 19

The retina could become damaged

Question 20

Explain how the thermoregulatory centre receives information about the temperature outside the body

Answer 20

Receptors on the skin send back nervous impulses to the thermoregulatory centre

Question 21

Describe what happens to excess glucose in the blood

Answer 21

It moves into liver and muscle cells and is converted to glycogen for storage

Question 22

What is the defining characteristic of type 1 diabetes

Answer 22

Uncontrolled high blood glucose level

Question 23

Explain how glucagon increases blood glucose concentration

Answer 23

Glucagon causes glycogen to be converted into glucose and be released into the blood

Question 24

Give two treatments a doctor would recommend for type 2 diabetes

Answer 24

A carbohydrate controlled diet and regular exercise

Question 25

Jim is obese but doesn't have diabetes. After he drinks the sugar drink, his blood glucose level rises and then Falls. Explain why this happens.

Answer 25

The blood glucose concentration starts increasing as glucose from the drink is absorbed into the blood. The pancreas detects a high blood glucose concentration and secrete insulin. Insulin causes the blood glucose concentration to fall back down.

Question 26

What process do the kidneys used to produce urine

Answer 26

Filtration

Question 27

A process in the kidneys Returns useful substances to the blood so that they are not lost in urine. What is the name of this process?

Answer 27

Selective reabsorption

Question 28

Name three useful substances that are returned to the Blood by selective reabsorption

Answer 28

Water, ions and glucose

Question 29

Give three ways water can be lost from the body

Answer 29

Breathing out from the lungs, sweating and urine

Question 30

Can the body control water loss from the skin

Answer 30

No

Question 31

In which organ are excess amino acids broken down

Answer 31

Liver

Question 32

What is the source of these extra amino acids

Answer 32

Protein in the diet

Question 33

What is a waste product of deamination

Answer 33

Ammonia

Question 34

Describe the body's response when the brain detects that water content is too low

Answer 34

A signal is sent to the pituitary gland to release more ADH ADH causes the kidneys to reabsorb more water This means less water is lost in the urine so the water content of blood is increased

Question 35

Describe the body's response when the brain detects that water content is too high

Answer 35

A signal is sent to the pituitary gland to release less ADH ADH causes the kidneys to reabsorb more water This means more water is lost in the urine so water content in the Blood is reduced

Question 36

Why might a person need a dialysis machine

Answer 36

If the kidneys don't work properly and remove waste product

Question 37

Why is it important that the dialysis fluid has the same concentration of dissolved substances as healthy blood

Answer 37

Otherwise useful substances will be lost from the blood

Question 38

Name three substances that should be present in dialysis fluid

Answer 38

Water, ions, and glucose

Question 39

What's the name of the gland that secretes FSH

Answer 39

Pituitary gland

Question 40

State two effects of fsh in women

Answer 40

Causes an egg to mature in the ovaries | Stimulates the ovaries to produce oestrogen

Question 41

What hormone stimulates the release of LH | Oestrogen

Answer 41

How does the hormone released by the contraceptive implant prevent pregnancy

Question 42

How does the hormone released by the contraceptive implant prevent pregnancy

Answer 42

the hormones inhibit fsh which stops eggs maturing

Question 43

Suggest an advantage of choosing the contraceptive injection over the pill

Answer 43

You don't need to remember to take it everyday

Question 44

What's the disadvantage of choosing the contraceptive injection over the pill

Answer 44

Side effects will last longer as it is always with you

Question 45

What's the role of thyroxine in the body

Answer 45

It regulates basal metabolism rate

Question 46

Describe the effect that adrenaline has on the body

Answer 46

It increases heart rate, which boost the delivery of oxygen to the brain and muscles and boosts the delivery of glucose to the brain and muscles