Senses

Question 1

If the organ is the eye, what is the stimulus and the receptor?

Answer 1

Stimulus - Light
Receptor - Photoreceptors in the retina

Question 2

If the organ is the ear , what is the stimulus and the receptor?

Answer 2

Stimulus - sound
Receptor - cilia/hairs in cochlea

Question 3

If the organ is the skin, what is the stimulus and the receptor?

Answer 3

Stimulus - Touch/temperature
Receptor - Thermoreceptors /Mechanoreceptors

Question 4

If the organ is the nose, what is the stimulus and the receptor?

Answer 4

Stimulus - Smell
Receptor - Chemoreceptor (odours)

Question 5

If the organ is the tongue, what is the stimulus and the receptor?

Answer 5

Stimulus - Taste
Receptor - Taste buds

Question 6

Iris

Answer 6

Helps control the amount of light entering the eye

Question 7

How can the skin and tongue detect stimuli and send information to the brain for processing?

Answer 7

The skin had mechanoreceptors and thermoreceptors, and the tongues chemoreceptors (taste buds) these convert the stimulus to mere impulses which travel to the brain along sensory neurons

Question 8

2 examples of reflex responses:

Answer 8

Blinking & Knee jerking

Question 9

Pupil

Answer 9

Black part of the eye. This is an opening that lets light in

Question 10

Lens

Answer 10

Focuses light onto the retina

Question 11

Blind spot

Answer 11

In this area there are no light-sensitive cells so this part of your retina can’t see.

Question 12

Sclera

Answer 12

The sclera is the white part of your eye. It’s a protective covering that wraps over most of your eyeball. It extends from the cornea at the front of your eye to the optic nerve in the back.

Question 13

Optic Nerve

Answer 13

Transfers electrical impulses from the retina for the brain for decoding

Question 14

Retina

Answer 14

Contains photosensitive rod and cone cells to produce electrical impulses from light stimuli

Question 15

In an investigation of the effects of caffeine, what is the independent variable?

Answer 15

Caffeine vs no Caffeine

Question 16

In an investigation of the effects of caffeine, what is the dependent variable?

Answer 16

The reaction speed (which can be calculated from reaction distance)

Question 17

In an investigation of the effects of caffeine, what would you hypothesise the result seen between a test with caffeine and test without?

Answer 17

Reaction speeds would be faster (smaller number) with caffeine as it is a stimulant

Question 18

How can you get more accurate and reliable data in an investigation in reaction times in male and females?

Answer 18

Test it with more males/females (not just 2), and repeat the test multiple times (per person) for reliability

Question 19

How does the reflex arc lead to a person moving their hand away from a hot flame?

Answer 19

1. The hot flame stimulus is detected by receptors in the skin.
2. A nerve impulse is then sent to the sensory neuron
3. to the spinal cord. Here it passes the synapse to a relay neuron
4. in the spina cord and quickly sent across another synapse to a motor neuron
   5.which interacts with an effector
5. muscle to move the arm

Question 20

What happens to the lens when focusing on a closer object?

Answer 20

It gets fatter to refract the light rays, so the ciliary muscles contract, and the suspensory ligaments relax

Question 21

What happens to the lens when focusing on a far object?

Answer 21

It gets thinner to refract the light rays more

Question 22

What happens in the pupil reflex to protect the eye from bright light

Answer 22

The pupils gets smaller to prevent as much light entering the eye. Radial muscles relax, circular muscles contract.

Question 23

Nervous pathaway (stimulus to response)

Answer 23

1. Stimulus
2. Receptor (pressure receptors)
3. Sensory neuron
4. Synapse
5. Relay neuron
6. Synapse
7. Motor Neuron
8. Effector
9. Response