B1d - The Nervous System

HideShow resource information
What is the 'Pupil' in the eye?
The Pupil is the gap in the iris
1 of 36
What is the function of the 'Lens' in the eye?
The Lens focuses light on the retina
2 of 36
What is the function of the 'Iris' in the eye?
The Iris controls how much light enters the pupil
3 of 36
What is the function of the 'Cornea' in the eye?
The Cornea refracts light as it enters the eye
4 of 36
What is the function of the 'Retina' in the eye?
The Retina contains light receptors, some are sensitive to lights of different colours.
5 of 36
What is the function of the 'Optic Nerve' in the eye?
The Optic Nerve carries impulses to the brain.
6 of 36
Describe the pathway of light.
The Iris controls the amount of light, that enters the eye. The rays of light are refracted by your cornea. The
7 of 36
What are the common Eye Defects?
Long-sighted, short-sighted and red-green colour blindness (inherited)
8 of 36
What causes 'Red-Green Blindness'?
Specialised cells in the retina that detect red / green light are missing
9 of 36
What causes Long and Short sight?
It is caused by the eyeballs or lens being the wrong shape, meaning that light ray cannot accurately focus on the retina
10 of 36
How can Long-sight be corrected?
Long Sight can be corrected by convex lens
11 of 36
How can short-sight be corrected?
Short Sight can be corrected by concave lens.
12 of 36
How can Laser Eye Surgery correct long / short sight?
Laser Eye surgey cuts a flap into the cornea, it folds it back and uses a aser to reshape the cornea. The shape of the cornea is corrected, causing a clear vision meaning that light rays can accurately focus on the retina.
13 of 36
What is Binocular Vision?
Binocular Vision is when eyes are positioned close together. It is commonly found on humans and predators.
14 of 36
What is the advantage of Binocular Vision?
It gives the ability to judge distance and speed accurately. It compares images from each eye, the more similar the images, the further away the object.
15 of 36
What is the disadvantage of Binocular Vision?
Each eye has a limited field of view.
16 of 36
What is Monocular Vision?
Monocular vision is when eyes are positioned on either side of the head. It is commonly found on preys.
17 of 36
What is the advantage of Monocular Vision?
It provides a wide field of view, meaning that it can see what is behind and what is in front.
18 of 36
What is the disadvantage of Monocular Vision?
It provide a poorer judgement of distance.
19 of 36
What is Accommodation?
Accommodation is when eyes have the ability to change their focus.
20 of 36
Explain how the eye focuses light when objects are near?
When objects are near, ciliary muscles contract, suspensory ligaments relax and lens are short and fat to refract light a lot.
21 of 36
Explain how the eye focuses light when objects are distant?
When objects are distant, ciliary muscles relax, suspensory ligaments contract and lens are long/thin so that light is only refracted a little.
22 of 36
What are neurones?
Neurones are specially adapted nerve cells
23 of 36
What are nerve impulses?
Nerve impulses are an electrical signal that is carried by nerve cells caused by neurones. They are carried along the axon.
24 of 36
What is the function of a 'sensory neurone'?
A Sensory Neurone carries never impulses from receptors to brain
25 of 36
What is the function of a 'relay neurone'?
A Relay Neurone makes connection between neurones inside your brain and your spinal cord.
26 of 36
What is the function of a 'motor neurone'?
A Motor Neurone carries nerve impulses from your brain to your muscles and glands.
27 of 36
How are neurones adapted?
They have elongated axon shape, which makes connections from one part of the body to another. They have insulating sheath, which speeds up the nerve impulse. They have dendrites -branched endings- to allow single neurone to act on many muscle fibres
28 of 36
What is a synapse?
A Synapse is a small gap between neurones.
29 of 36
What happens in a synapse?
An electrical impulse travels down a neurone until it reaches a synapse. A Transmitter substance diffuses across the synapse. Transmittor binds with receptor molecules on the next neurone, which causes a electrical impulse to be initiated in neurone.
30 of 36
What is a Voluntary Action?
It is an action carried under the concious control of the brain, you decide how to react to the stimulus.
31 of 36
What is the Voluntary Action Pathway?
Stimulus, Recptors, Sensory Neurones, Brain, Motor Neurone, Effector, Response
32 of 36
What is a reflex action? / involuntary response.
A Reflex Action is a fast, automatic and protective response.
33 of 36
What is the Reflex Action Pathway?
Stimulus, Receptors, Sensory Neurone, Spinal Cord, Motor Neurone, Effector, Response.
34 of 36
What is the Central Nervous System - CNS?
It is the Brain and Spinal Cord
35 of 36
What is the Peripheral Nervous System - PNS?
It includes receptors and neurones.
36 of 36

Other cards in this set

Card 2

Front

What is the function of the 'Lens' in the eye?

Back

The Lens focuses light on the retina

Card 3

Front

What is the function of the 'Iris' in the eye?

Back

Preview of the front of card 3

Card 4

Front

What is the function of the 'Cornea' in the eye?

Back

Preview of the front of card 4

Card 5

Front

What is the function of the 'Retina' in the eye?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Nervous system, hormones and behaviour resources »