Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology Yr 9 > The Nervous System and the Eye > Flashcards

The Nervous System and the Eye Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What is a neurone?

A

Specialised cells which transmit information through nerve responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a nerve?

A

A bundle of several neurones

Nerve cell = a single neurone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a nerve impulse?

A

Electrical signal (current) that travels along a neurone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Two examples of reflexes

A

Knee jerk reflex

Pupil reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the cell body?

A

The part of a neurone which contains the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the dendrite?

A

Extensions at which nerve impulses are received from other cells at synapses and transmitted to the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the axon?

A

Extension which carries nerve impulses to other neurone or effector organ (muscle or gland)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the myelin sheath?

A

Fatty sheath which insulates the axon (preventing short-circuits of electrical impulses) and speeds up the conduction of nerve impulses, made of Schwann cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the steps of the reflex arc?

A
  • Stimulus (could be pain)
  • Receptor
  • Sensory neurone (anywhere where you feel sense)
  • Relay neurone (in the central nervous system)
  • Motor neurone
  • Effector (muscle, gland)
  • Response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Way to remember the reflex arc?

A 
Steve 
Receives 
Stamps 
Regularly 
Meanwhile
Emily 
Runs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is a reflex?

A

Involuntary and almost immediate response to a stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the central nervous system consist of and how is it linked to the sense organs?

A

The brain and the spinal cord are the two parts of the central nervous system. They are linked to the sense organs by nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the three parts of the spine?

A

Intervertebral disc
Spinal cord
Vertebral column (encloses and protect the spinal cord)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a synapse?

A

A tiny gap between 2 neurones across which impulses pass by diffusion of a neurotransmitter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is are neurotransmitters?

A

Chemicals that transmit signals from one neurone to another across a synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Two examples of diseases linked to defective neurotransmitter function

A

Schizophrenia

Depression

17
Q

Steps of transmitting of a nerve impulse across a synapse

A
  • Nerve impulse travels along the axon to the synapse in the form of an electrical signal
  • The vesicles containing the neurotransmitters move to the membrane of the axon terminal
  • Neurotransmitter is emptied into the synapse
  • Neurotransmitter diffuses across the synapse
  • Neurotransmitter binds to the receptor on the surface of the dendrite
  • Binding of the neurotransmitter triggers a new nerve impulse
  • The nerve impulse travels along the dendrite to the axon
18
Q

What is the function of the conjunctiva in the eye? And what is it?

A

It is a layer covering the cornea and sclera

Helps lubricate the eye

19
Q

What is the function of the cornea in the eye? And what is it?

A

It is a clear covering over the eye

Helps refract and focus light

20
Q

What is the function of the lens in the eye? And what is it?

A

It a transparent structure behind the pupil

Refracts and focuses light

21
Q

What is the function of the pupil in the eye? And what is it?

A

It is a hole in the centre of the iris

Controls the amount of light entering the eye

22
Q

What is the function of the iris in the eye? And what is it?

A

It is a pigmented tissue

Controls the amount of light entering the eye

23
Q

What is the function of the suspensory ligaments in the eye? And what are they?

A

They are ligaments connecting the ciliary muscle and the lens
Involved in controlling accommodation

24
Q

What is the function of the ciliary muscle in the eye? And what is it?

A

It is a ring of muscle connected to the lens via suspensory ligaments
Controls accommodation

25
Q

What is the function of the retina in the eye? And what is it?

A

It is the inner layer of the eye containing photoreceptors (rods + cones)
Responds to light stimulus

26
Q

What is the function of the optic nerve in the eye? And what is it?

A

It is a sensory nerve (part of the CNS)

Carries nerve impulses from retina to brain

27
Q

What process happens to the pupil in dim light which allows it to dilate?

A
  • The stimulus of a dim light is picked up by the retina which sends a nerve signal to the optic nerve.
  • The optic nerve acts as a sensory neurone and sends the signal to the CNS
  • The nerve signal goes through a relay neurone and into a motor neurone
  • The signal is sent to the muscles in the iris which respond
28
Q

What are the muscles in the iris?

A

Radial muscles

Circular muscles

29
Q

What happens in the iris when in dim light?

A
  • Radial muscles contract
  • Circular muscles relax
  • Pupil dilates (gets bigger)
30
Q

What happens in the iris when in bright light?

A
  • Radial muscles relax
  • Circular muscles contract
  • Pupil gets smaller
31
Q

What do rods do in the retina?

A

Help with vision in dim light

32
Q

What do cones do in the retina?

A

Provide colour vision

33
Q

What is accommodation in the eye?

A

The reflex that makes the eye focus on an object by changing the shape of its lens

34
Q

What happens to light that is reflected from an object?

A

The light is refracted (bent) by the cornea and the lens forming an upside down image on the retina

35
Q

What causes short sightedness and how can it be cured?

A

The eye is too long so the point of focus is before the retina
Corrective concave lenses are used

36
Q

What causes far sightedness and how can we cure it?

A

The eye is too short so the point of focus is behind the retina
Corrective convex lenses are used

Biology Yr 9 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions