B10

Question 1

Homeostasis

Answer 1

Homeostasis is the regulation of the internal conditions of a cell or organism to maintain optimum conditions for function, in response to internal and external changes.

Question 2

Receptor

Answer 2

Detects changes in the environment

Question 3

Effector

Answer 3

Muscles or glands that bring about responses

Question 4

Stimulus

Answer 4

Change in the environment

Question 5

Coordination centre

Answer 5

Receives, processes information and coordinates responses

Question 6

How can the ACS communicate information

Answer 6

Through the nervous system and hormonal communication etc

Question 7

ACS ORDER

Answer 7

Stimulus - receptor - control centre - effector - response

Question 8

What makes up the CNS

Answer 8

Brain - spinal cord - neurones

Question 9

Homeostasis controls internal conditions such as

Answer 9

body temperature, pH levels, water levels, co2 levels and blood glucose concentration

It’s important for maintaining optimum conditions for the enzyme action and all cell functions.

Question 10

Synapse

Answer 10

electrical impulse arrives at the end of a neurone causing vesicles containing a chemical called a neurotransmitter to be released into the synapse.
The neurotransmitter diffuses across the synapse and binds to chemical receptors on the next neurone.
This causes an electrical impulse to be generated in the next neurone

Question 11

Main stages of a reflex arc

Answer 11

Stimulus - receptor - sensory neurone - relay neurone - motor neurone - effector - response

Question 12

How does the eye work

Answer 12

Light enters the eye
Refracts through the cornea
Refracts through the lens
Lens changes thickness to focus light
Image formed on the retina

Question 13

Cornea

Answer 13

A curved transparent membrane at the front of the eye; most of the refraction takes place here.

Question 14

Iris

Answer 14

The coloured part of the eye

Question 15

Pupil

Answer 15

A hole where light passes through - can change in diameter

Question 16

Lens

Answer 16

Flexible - focusses image on retina - ciliary muscles contract and therefore squashing the lens so that it can have a shorter focal length so it can see stuff closer

Question 17

To focus on a near object

Answer 17

the ciliary muscles contract
the suspensory ligaments loosen
the lens is then thicker and refracts light rays strongly.

Question 18

To focus on a distant object

Answer 18

Ciliary muscles relax
Suspensory ligaments get pulled tight
Lens is then pulled thin so little refraction of light occurs

Question 19

Accommodation

Answer 19

Accommodation is the process of changing the shape of the lens to focus on near or distant objects.

Question 20

What are the two common defects of the eye

Answer 20

Myopia and hyperopia

Question 21

Hyperopia can be foxed with a _______ lens

Answer 21

Convex

Question 22

Myopia can be foxed with a _______ lens

Answer 22

Concave

Question 23

New technologies on fixing eyes are

Answer 23

Contact lenes
Laser eye surgery to change the shape of cornea as it does most of the refracting
Replacement lens (can risk damaging retina)

Question 24

Medulla

Answer 24

Unconscious activities - breathing heart beat

Question 25

Cerebral cortex

Answer 25

Conscious activities - memory language

Question 26

Cerebellum

Answer 26

Muscle contraction and balance

Question 27

Electrical stimulation

Answer 27

Because the nervous system communicates using electrical impulses, electrical stimulation is used to help treat conditions such as Parkinson’s disease (causes tremors)

Question 28

MRI

Answer 28

have allowed us to learn which areas of the brain are active during different activities, such as moving, speaking and listening

Question 29

Brain damage

Answer 29

By studying patients with brain damage, where part of their brain doesn’t function, neuroscientists have been able to link particular regions of the brain to particular functions.