B1 - Coordination And Control

Question 1

What is a receptor?

Answer 1

A cell that detects stimuli.

Question 2

Give five of the receptors on the body.

Answer 2

Ears, eyes, nose and tongue, skin

Question 3

Explain how information is passed to the brain.

Answer 3

Once a sensory receptor detects a stimulus, an impulse is sent along the sensory neurons up to the CNS.

Question 4

How is information passed to the organs?

Answer 4

Impulses are sent from the CNS along motor neurons to the effector organs which are muscles or glands.

Question 5

What is a reflex?

Answer 5

Some responses to stimuli are automatic and rapid.

Question 6

Why are reflexes important?

Answer 6

Reflexes run everyday actions and prevent danger and damage.

Question 7

What are the three types of neuron?

Answer 7

• Sensory
• Motor
• Relay

Question 8

What is a synapse?

Answer 8

A gap between two nerves.

Question 9

How do electrical impulses travel across the synapse?

Answer 9

• The impulse arrives at the synapse,
• chemicals are released into the gap between the neurons,
• the chemicals attach to the opposite neuron and form a new electrical impulse.

Question 10

Give the general sequence of a reflex action.

Answer 10

Stimulus –> receptor –> coordinator –> effector –> response

Question 11

How is the menstrual cycle controlled?

Answer 11

Hormones control the release of an egg and build of lining in the womb.

Question 12

What are the three hormones that control the menstrual cycle?

Answer 12

FSH, oestrogen and LH.

Question 13

Where is FSH released from?

Answer 13

The pituitary gland.

Question 14

What is ovulation?

Answer 14

The maturing of an egg.

Question 15

Where is the pituitary gland?

Answer 15

At the bottom of the brain.

Question 16

What does FSH stand for?

Answer 16

Follicle stimulating hormone.

Question 17

What two factors does FSH cause?

Answer 17

• Egg maturing

- Stimulates the ovary to produce oestrogen

Question 18

Where is oestrogen released from?

Answer 18

The ovaries.

Question 19

What three factors does oestrogen cause?

Answer 19

• The lining of the womb to develop
• The inhibition of FSH production
• Stimulates the release of the mature egg.

Question 20

What does LH stand for?

Answer 20

Luteinising hormone.

Question 21

How can hormones prevent pregnancy?

Answer 21

Some contraceptives contain hormones which stop FSH production.

Question 22

How can hormones be used to improve fertility?

Answer 22

FSH can be used to stimulate eggs to mature which can be used for IVF.

Question 23

What does IVF stand for?

Answer 23

In vitro fertilisation

Question 24

What is the Fallopian tube?

Answer 24

The tube between the ovary and womb.

Question 25

Give three advantages of using fertility treatment.

Answer 25

• Families can be much smaller.
• Population growth can be controlled.
• The eggs can be stored for later use.

Question 26

Give three disadvantages of using fertility treatment.

Answer 26

• The pill can cause health problems.
• The pill can be expensive.
• Some religious groups dislike contraception.

Question 27

Give four conditions that have to be controlled in the body.

Answer 27

• Core body temperature
• Water level
• Ion level
• Blood sugar level.

Question 28

What is homeostasis?

Answer 28

The controlling of conditions in the body.

Question 29

How are the levels of water and salts controlled?

Answer 29

The kidneys control how much salt and water is lost in the urine.

Question 30

What stimuli are plants responsive to?

Answer 30

Light, moisture and gravity.

Question 31

Which hormones cause responses in plants?

Answer 31

Auxin

Question 32

How do plants react to gravity?

Answer 32

Plant roots grow downwards into soil to get water and minerals.

Question 33

How do plant shoots react to different conditions?

Answer 33

Shoots are sensitive to light and gravity so the plant grows towards the light.

Question 34

What is phototropism?

Answer 34

The response of a plant to light.

Question 35

What is geotropism/gravitropism?

Answer 35

The response of a plant to gravity.

Question 36

How does auxin control the response of a plant?

Answer 36

The auxin hormone is unevenly distributed causing an unequal growth rate.

Question 37

How does auxin relocate in accordance to light?

Answer 37

• Auxin moves to the unlit side so the shoot bends.

- When whole of the shoot is lit, the levels of auxin is even meaning the shoot grows straight.

Question 38

How does auxin effect roots and shoots?

Answer 38

Auxin inhibits growth in roots and promotes growth in shoots.

Question 39

How can plant hormones be used?

Answer 39

• Gardeners use hormones as rooting powder for cuttings.

- Farmers can use hormones as weed killer.

Question 40

How do plant hormones kill weeds but not other crops?

Answer 40

• Weeds are broad leafed and absorb a lot of hormones making them grow uncontrollably, hence killing them.
• Narrow leafed plants such as grass and cereal are unaffected.

Question 41

Give an advantage of using FSH for older women.

Answer 41

They are able to have a baby.

Question 42

Give one example of when the use of a plant hormone has caused excessive damage.

Answer 42

Agent Orange

Question 43

What is the purpose of the nervous system?

Answer 43

To enable the body to react quickly to the surroundings.