Brainscape's Knowledge GenomeTM

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


See full index

IGCSE Biology > Chapter 14: Coordination and Response > Flashcards

Chapter 14: Coordination and Response Flashcards

1
Q

What is the nervous system

A

The nervous system is the major controlling, regulatory and communicating system in the body.

It is the centre of all mental activity, including thought, learning and memory.

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

What is the nervous system responsible for?

A

regulating and maintaining homeostasis along with the endocrine system.

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

How does the nervous system help us keep in touch with the environment?

A

The receptors help us keep in touch with our internal and external environment.

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

What are the two types of nervous systems?

A

CNS - central nervous system

PNS - peripheral nervous system

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

What is the CNS consist of?

A

the brain
the spinal cord

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

What does the PNS consist of?

A

motor and sensory neurons that connect all parts of the body to the CNS.

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

Define nerve impulses.

A

A nerve impulse is an electrical signal that passes along nerve cells called neurons.

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

What are stimuli?

A

Detectable changes in the internal or external environment that influence or cause a temporary change in activity or response.

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

Give some examples of stimuli.

A

Light
Gravity
Water
Chemicals
Pressure
Temperature
Pain
Movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are voluntary actions?

A

Actions controlled by conscious thought

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Give some examples of voluntary actions.

A

Walking
Raising your hand

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

What do voluntary actions allow us to do?

A

respond with the benefit of experience

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

Which part of the brain are voluntary actions controlled by?

A

The cerebrum - coordinates incoming information and then sends messages to effects

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

Tell me the speed of voluntary actions.

A

Slow

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

What type of response do voluntary actions result in?

A

The same stimulus may produce a variety of responses.

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

What are involuntary actions?

A

Actions that do no involve thought

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Give examples of involuntary actions.

A

Peristalsis
Cardiac muscle contractions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do involuntary actions allow us to do?

A

to respond quickly to avoid danger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are involuntary actions controlled by?

A

Hind-brain
Spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Tell me the speed of involuntary actions

A

Rapid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What type of response do involuntary actions result in?

A

The same stimulus always results in the same response.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are neurons.

A

Specialised cells adapted to carry electrical impulses from one place in the body to another.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Tell me the parts of the neurone.

A

Cell body containing nucleus
Dendrites
Axon
Myelin Sheath
Nerve ending (motor end plate)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the three types of neurons.

A

Sensory
Relay
Motor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

In which direction do sensory neurons carry electrical impulses.

A

Receptor —-> CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

In which direction do relay neurons carry electrical impulses.

A

CNS —-> CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

In which direction do motor neurons carry electrical impulses?

A

CNS —-> Effector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are human reflex actions controlled by?

A

The reflex arc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is a reflex action?

A

The means of automatically and rapidly integrating and coordinating stimuli with the responses of effectors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Why are reflex actions important?

A

Because they protect us when our safety is at risk and a rapid response is needed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Describe the pathway of the reflex arc.

A

stimulus –> receptor –> coordinator –> effector –> response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Describe how reflex actions take place?

A
  1. The receptor in the skin detects a stimulus (e.g. a change in temperature)
  2. The sensory neurone sends impulses to relay neurone.
  3. A motor neuron sends impulses to the effector.
  4. The effector produces a response (the muscle contracts to move the hand away).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Define synapse.

A

The synapse is the gap between two neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is a synapse a combination of?

A

Presynaptic endings
Synaptic clefts
Postsynaptic endings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What does a presynaptic ending contain?

A

It contains neurotransmitter molecules (chemical messengers)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are synaptic clefts?

A

the gap between the two neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are postsynaptic endings?

A

They contain the sites for receptor proteins (molecules which receive signals for a cell)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Describe what happens at a synapse.

A
  1. Neurotransmitters are packed into small, membrane bound synaptic vesicles.
  2. Each vesicle contains thousands of neurotransmitter molecules.
  3. When an impulse arrives at the synapse, vesicles in the cytoplasm release a tiny amount of the neurotransmitter.
  4. These rapidly diffuse across the gap and bind to the receptor protein in the membrane of the neuron on the other side of the synapse.
  5. This sets of an impulse in the neuron.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What do synapses ensure?

A

the unidirectionality of nervous impulses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Why can’t a nerve impulse travel backwards?

A

Because the vesicles containing the neurotransmitter are only present in the presynaptic neuron.

41
Q

How do stimulants act on synapses?

A

Stimulants like caffeine releases neurotransmitters like dopamine and serotonin into the synapse.

42
Q

How do depressants act on synapses?

A

Depressants such as heroin and alcohol inhibit synapses by blocking the receptors on the postsynaptic neuron so that impulses cannot be sent.

43
Q

Draw and label the eye.

A
44
Q

State the function of the cornea.

A

Bends/refracts light as it enters the eye

45
Q

State the function of iris.

A

Controls the amount of light entering the pupil (coloured part of the eye)

46
Q

State the function of lens.

A

Focuses the light on the retina

47
Q

State the function of retina.

A

Contains light receptors

48
Q

State the function of optic nerve.

A

Carries impulses between the eye and the brain

49
Q

How do pupils dilate?

A

The radial muscles contract.
The circular muscles relax.

50
Q

How do pupils constrict?

A

Circular muscles contract
Radial muscles relax

51
Q

How does the eye produce a focused image of a near or distant object?

A

The lens changes shape.
It becomes fatter for near objects and thinner for distant objects.
This change in shape is caused by contracting/relaxing the ciliary muscles.

52
Q

What are the two types of photo receptors.

A

Rods
Cones

53
Q

State the function of rod cells.

A

Plays an important role in night/low light vision

54
Q

State the function of cones.

A

Bright light/colour vision.
There are three types one responding best to red, green and blue.
If all three types are equally stimulated we get the sensation of white light.

55
Q

What is fovea?

A

It is the central part of the retina where the cone cells are concentrated.

56
Q

What is the blindspot?

A

The point where the optic nerve leaves the retina, where there are no sensory cells.

57
Q

Define Hormone.

A

Hormones are chemical substances that help to regulate processes in the body.

58
Q

Where are hormones produced?

A

They are produced by an endocrine gland and are carried by the blood to their target organs to alter their activity.

59
Q

Where is Adrenaline produced?

A

Adrenal gland

60
Q

What are the target organs of adrenaline?

A

All vital organs e.g. heart, lungs, liver

61
Q

State the function of adrenaline.

A

Prepares the body for ‘fight or flight’ situations where a rapid response is needed.

62
Q

Where are insulin and glucagon produced?

A

In the pancreas

63
Q

State the target organ of insulin and glucagon.

A

Liver

64
Q

State the function of insulin.

A

Causes the liver to reduce blood glucose levels

65
Q

State the function of glucagon.

A

Causes the liver to increase blood glucose levels.

66
Q

Where is testosterone produced?

A

In the testes.

67
Q

What are the target organs of testosterone.

A

Male reproductive organs

68
Q

State the function of testosterone.

A

Controls puberty in males

69
Q

Where is oestrogen and progesterone produced?

A

Ovaries

70
Q

What are the target organs of oestrogen and progesterone?

A

Female reproductive organs and pituary gland

71
Q

What does oestrogen do?

A

Controls puberty and menstrual cycle in females

72
Q

What does progesterone do?

A

Maintains the lining of the womb, maintains pregnancy.

73
Q

What type of response does hormonal control do compared to nervous control?

A

Slow but long-lasting response

74
Q

Define homeostasis.

A

It is the maintenance of a constant internal environment, within narrow limits.

75
Q

Give examples of homeostasis.

A

Maintenance of:
- concentration of nutrients/ions
- acidity
- temperature

76
Q

How is the constant environment achieved?

A

By negative feedback

77
Q

How does negative feedback operate?

A

It operates on the principles:
- If the level of something rises, control systems reduce it again
vice versa

78
Q

How do you regulate blood sugar?

A

Pancreas monitors blood glucose levels in the body
It releases insulin when blood glucose levels are high
This triggers the liver to store excess glucose as glycogen
When blood glucose is low, glucagon is released.
It triggers the liver to convert the stored glycogen into glucose and release it into the bloodstream to bring the levels back to normal.

79
Q

What is type 1 diabetes?

A

A condition in which the blood glucose levels remain too high because the pancreas is unable to make enough insulin

80
Q

What are the symptoms of Type 1 Diabetes?

A
  1. feeling tired
  2. thirsty
  3. frequent urination
  4. weight loss
81
Q

How do you treat Type 1 Diabetes?

A
  1. By injecting insulin
  2. Monitoring diet

The extra insulin causes liver to convert glucose into glycogen which reduces blood glucose level.

82
Q

What parts does the human skin consist of?

A

epidermis
dermis
fatty tissue

83
Q

What does the epidermis contain?

A

The basal layer with skin pigment cells producing melanin

84
Q

What does the dermis contain?

A

Connective tissue
Hair follicles
Sweat glans
Blood vessels
Nerve endings

85
Q

What does the fatty tissue do?

A

Insulates the body

86
Q

How is body temperature controlled in the skin?

A
87
Q

What happens when your body over heats?

A

More blood flows near the surface of skin (due to vasodilation) allowing more heat to be exchanged with the surroundings

Sweating - when sweat evaporated, it takes heat from the body and cools it down

88
Q

What happens when your body over cools?

A

Less blood flows near surface of skin - reduces heat loss to surroundings

Sweat production stops

Shivering - muscular contractions release heat as a result of respiration in muscles

89
Q

Define vasodilation.

A

The widening of the arterioles in the dermis

90
Q

Define vasoconstriction.

A

The narrowing of the arterioles in the skin

91
Q

What is positive tropism?

A

Growth towards a stimulus

92
Q

What is negative tropism

A

Growth away from a stimulus

93
Q

Define Geotropism.

A

Response in which plants grow towards or away from gravity

94
Q

Define phototropism

A

A response in which a plant grows towards or away from the direction in which light is coming

95
Q

Advantages of positive geotropism in roots.

A
  1. Firm anchorage in the soil
  2. reaches more water
96
Q

Advantages of positive phototropism in leaves.

A
  1. exposed to more sunlight and do more photosynthesis
  2. flowers seen by insects
  3. higher chance of seed dispersal
97
Q

What is auxin?

A

A plant growth hormone.

98
Q

Where is auxin produced?

A

In the shoot tip of the plant
It triggers the phototrophic response

99
Q

How is auxin distributed?

A

Unequally with higher concentrations on the underside compared to the upper side.

This causes the cells to elongate and lose turgidity allowing the shoot to bend towards the light source

IGCSE Biology (21 decks)

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