Co-ordination And Control

Question 1

What are the 3 main components of responding to a stimulus?

Answer 1

Receptors
Coordinator
Effector

Question 2

What does the receptor do?

Answer 2

Receives / detects the stimulus

Question 3

What does the coordinator do?

Answer 3

Determines the response

Question 4

What does the effector do?

Answer 4

Carries out the response

Question 5

What is the CNS

Answer 5

This is the brain and spinal cord. Together they are known as the central nervous system.

Question 6

What does the aqueous and vitreous humour do for the eye.

Answer 6

Fluid that is needed to support the eye balk and allow light to pass through the eye to the retina

Question 7

What is the function of the iris

Answer 7

Control how much light enters the eye

Question 8

What is the function of the pupil

Answer 8

Space in the iris through which light passes

Question 9

What is the function of the cornea

Answer 9

Transparent front part of the eye that causes some bending (refraction) of light

Question 10

What is the function of the conjunctiva

Answer 10

Thin transparent protective outer covering that helps prevent the entry of microorganisms.

Question 11

What is the function of the retina

Answer 11

Layers of light sensitive cells that can sense different coloured light (cone cells) as well as cells that don’t sense colour at all (rods)

Question 12

What is the function of the lens

Answer 12

Refracts light to obtain a focused image

Question 13

What is the function of the optic nerve

Answer 13

A bundle of neurones that carries impulses from the retina to the brain

Question 14

How does the eye focus

Answer 14

By changing the shape of the lens

Question 15

How does the eye focus on distant objects

Answer 15

The ciliary muscles relax, suspensory ligaments are pulled tight, this pulls the lens thin

Question 16

How does the eye focus on near objects

Answer 16

Ciliary muscles contract, suspensory ligaments slackened, lens allowed to bulge

Question 17

How are nurones adapted to carry electrical impulses

Answer 17

Long length- to carry impulses long distances
Insulating sheath- to allow rapid transmission of impulses
Branding ends- to receive or pass impulses to many other nerve cells

Question 18

What are synapses

Answer 18

They are tiny gaps between nerve cells

Question 19

What happens when an impulse reaches a synapse

Answer 19

1.The impulse reaches the synaptic bulb (end of neurone)
2.Vesicles containing the transmitter move towards the cell membrane at the synapse
3.Vesicles release their neurotransmitter into the gap between the 2 cells
4.Neurotransmitter diffuses across the gap
5.The neurotransmitter reaches the membrane of the next cell
6.When enough neurotransmitter reaches the next cell an impulse will occur
7.The impulse travels along the next cell
8.The used neurotransmitter is broken down by an enzyme

Question 20

What are vesicles

Answer 20

Vesicles are “tiny packages” that carry the neurotransmitter

Question 21

What are the the 2 basic types of response

Answer 21

Voluntary actions
Reflex actions

Question 22

What is a voluntary action

Answer 22

It is a response where we have voluntary control over the action. The brain is the coordinator

Question 23

What is a reflex action?

Answer 23

We are not conscious of these actions. Reflex actions tend to be much faster as they use a special pathway of nerves called the reflex arc.

Question 24

What are hormones?

Answer 24

They are chemicals produced by special glands in the body that can travel through the blood to target organs in order to produce temporary changes in the way the cells function.

Question 25

What is the difference between hormones and neurones

Answer 25

Hormones are slow acting Neurones are fats acting

Question 26

Which hormone controls blood sugar levels

Answer 26

Insulin

Question 27

How does insulin reduce blood sugar

Answer 27

It travels through blood stream to its target organ the liver It will increase the cells uptake of glucose Increase the respiratory rate And convert glucose into glycogen for storage

Question 28

What mechanism is used to control blood glucose levels

Answer 28

Negative feedback

Question 29

What is diabetes

Answer 29

A condition where people fail to produce enough insulin or fail to respond to it correctly.

Question 30

What are symptoms of diabetes

Answer 30

High glucose levels Glucose in urine Excessive thirst Lethargy The frequent need to urinate

Question 31

What are long term damages of diabetes if it is left untreated

Answer 31

Kidney damage, eye damage, stroke, and heart disease

Question 32

What hormone is responsible for how much urine our kidneys produce

Answer 32

ADH

Question 33

What does the ADH do

Answer 33

It allows the medulla of the kidneys to resorb more water into the blood.

Question 34

What do plants grow towards the light

Answer 34

This would increase the rate of growth as more photosynthesis can occur. This is known as phototropism.

Question 35

What hormone is responsible for phototropism

Answer 35

Auxin

Question 36

How does the plant bend towards the light

Answer 36

The auxin gathers in the shaded side. The auxin elongates the cells making the shaded side longer causing it to bend towards the light.

Question 37

What term describes the changes in the focusing of the lens

Answer 37

Accommodation

Question 38

What is osmoregulation

Answer 38

The process in which the water levels in blood is controlled by kidneys and hormone ADH

Question 39

What is type 1 diabetes

Answer 39

A condition which usually occurs in early life when the pancreas stops producing insulin, which then has to be taken as medication throughout life

Question 40

What is type 2 diabetes

Answer 40

Progressive disease linked to lifestyle factors and obesity. Pancreas gradually produces less insulin.