Brainscape's Knowledge GenomeTM

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


See full index

Biology AQA Triple > Homeostasis > Flashcards

Homeostasis Flashcards

Paper 2 - B5

1
Q

What is homeostasis?

A

Regulation of internal conditions of a cell or organisms to maintain optimum conditions for function in response to internal and external changes

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

Which molecules in the body are affected by homeostasis and need optimal conditions?

A

Enzymes

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

State 3 things that are controlled (kept constant) by homeostasis

A

Body temperature, blood glucose concentration, water levels

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

Homeostasis relies on automatic control systems. Which two systems are involve in coordinating these responses?

A

Nervous system, endocrine system

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

What do receptors do?

A

Detect stimuli (changes in the environment)

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

Name 3 coordination centres involved in different aspects of homeostasis

A

Brain, spinal cord, pancreas

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

Name the two types of effector which bring about responses in the body

A

Muscles or glands

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

What is the function (job) of the nervous system?

A

To enable humans to react to their surroundings and coordinate their behaviour

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

What type of signal travels along a nerve?

A

An electrical impulse

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

Which two organs make up the central nervous system (CNS)?

A

Brain and spinal cord

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

Put the following words in the correct order to show the stages in a reflex arc: effector, receptor, motor neurone, response, sensory neurone, coordinator (CNS), stimulus

A

Stimulus –> receptor –> sensory neurone –> coordinator –> motor neurone –> effector –> response

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

Where are relay neurones found?

A

Inside the central nervous system (brain and spinal cord)

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

What is a synapse?

A

A gap between two neurones

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

What happens at a synapse between two neurones?

A

A chemical is released so that a new impulse begins in the next neurone

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

What is a reflex action? Why are they important?

A

An automatic and rapid response to a stimulus. They are important for survival and protection from harm. They do not involve the conscious part of the brain

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

(Triple only) What is the brain made of?

A

Billions of interconnecting neurones

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

(Triple only) What is the function of Cerebral cortex in the brain?

A

It is responsible for conscious thought,
movement and processing sensory
information

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

(Triple only) What is the function of the cerebellum in the brain?

A

Balance and coordination of movement

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

(Triple only) What is the function of the medulla in the brain?

A

Unconscious processes such as control of heart rate and breathing rate

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

(Triple only) Why is it difficult to investigate brain function and treat brain damage/disease?

A

The brain is a very complex and delicate organ and difficult to map. Different areas of the brain often work together. Technologies to analyse brain activity are relatively new (and involve being inside a scanner).

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

(Triple only) Give three techniques used by scientists to map the regions of the brain to particular functions

A

Studying patients with brain damage; MRI scans; electrically stimulating different parts of the brain

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

(Triple only) What is ‘accommodation’ in the eye?

A

How the lens changes shape to focus on near and distant objects

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

(Triple only) Name the structures involved in accommodation in the eye

A

Lens, suspensory ligaments, ciliary muscles

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

(Triple only) How does the eye adapt to dim light and which structures are involved?

A

The pupil dilates to let in more light. This involves circular muscles in the iris relaxing and radial muscles contracting

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

(Triple only) What two things are the receptors in the eye sensitive to?

A

Light intensity and colour

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

(Triple only) What is the function of the retina in the eye?

A

Contains light sensitive receptors

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

(Triple only) How are impulses from the eye transmitted to the brain?

A

Via the optic nerve

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

(Triple only) Name the tough white outer coating of the eye

A

The sclera

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

(Triple only) What is the role of the cornea?

A

To refract light

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

(Triple only) What is the function of the lens?

A

To focus light to a point on the retina

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

(Triple only) In accommodation in the eye, when focusing on a near object, what do the ciliary muscles, suspensory ligaments and lens do?

A

Ciliary muscles contract, suspensory ligaments loosen, lens is thicker and refracts light rays more strongly

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

(Triple only) In accommodation in the eye, when focusing on a distant object, what do the ciliary muscles, suspensory ligaments and lens do?

A

Ciliary muscles relax, suspensory ligaments are pulled tight, lens is pulled thin and refracts light rays less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

(Triple only) What is the scientific name for short-sightedness?

A

Myopia

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

(Triple only) What is the scientific name for long-sightedness?

A

Hyperopia

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

(Triple only) What type of lens is required to treat hyperopia?

A

Convex

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

(Triple only) What type of lens is required to treat myopia?

A

Concave

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

(Triple only) In which eye defect is light focused to a point in front of the retina rather than directly onto it?

A

Myopia

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

(Triple only) Give three alternatives to spectacle lenses to treat eye defects

A

Hard & soft contact lenses, laser surgery to change shape of cornea, replacement lens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

(Triple only) Which part of the brain monitors and controls body temperature?

A

Thermoregulatory centre

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

(Triple only) Name two places in the body where temperature receptors are found and which temperature they detect

A

On skin to detect surface temperature; In thermoregulatory centre of brain to detect blood temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

(Triple only) Which response to temperature involves blood vessels to the skin dilating, and does this occur when temperatures are too high or too low?

A

Vasodilation; when too high

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

(Triple only) What is vasoconstriction and when does it occur?

A

When blood vessels to the skin constrict, when body temperature is too low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

(Triple only) Give the two body responses to an increase in body temperature

A

Sweating and vasodilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

(Triple only) Give the two body response to a decrease in body temperature

A

Shivering and vasoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

(Triple only) How does shivering warm the body?

A

Rapid muscle contractions increase rate of respiration and release heat energy

46
Q

Name the system in the body that controls hormonal communication

A

The endocrine system

47
Q

What name is given to the organs of the endocrine system?

A

Glands

48
Q

How do hormones travel around the body?

A

In the bloodstream

49
Q

What name is used to refer to any part of the body that a hormone acts on

A

A target organ

50
Q

Give two differences between a nervous and hormonal response

A

Hormonal is slower but acts for longer

51
Q

Which gland is called the ‘master gland’ because it secretes hormones that act on other glands?

A

Pituitary gland

52
Q

Where is the pituitary gland located?

A

At the base of the brain

53
Q

Where is the pancreas located?

A

In the middle of the left side of the body, below the stomach, above intestines

54
Q

Where is the thyroid gland located?

A

In the neck

55
Q

Where are the adrenal glands located?

A

On top of the kidneys

56
Q

Which organ monitors and controls blood glucose concentration?

A

Pancreas

57
Q

Which hormone is released when blood glucose levels are too high?

A

Insulin

58
Q

Which hormone is released when blood glucose levels are too low?

A

Glucagon

59
Q

In control of blood glucose levels, what chemical is excess glucose converted into, and which two organs store this?

A

Glycogen in liver and muscle cells

60
Q

Name the disease in which the pancreas fails to produce enough insulin

A

Type 1 diabetes

61
Q

Name the disease in which the body cells no longer respond to insulin

A

Type 2 diabetes

62
Q

Which type of diabetes is treated using insulin injections?

A

Type 1 diabetes

63
Q

What is the usual treatment for type 2 diabetes?

A

A carbohydrate controlled diet and an exercise regime

64
Q

What is the main risk factor for type 2 diabetes?

A

Obesity

65
Q

What is Negative Feedback?

A

A process whereby a change in a factor brings about an action which reverses the change

66
Q

(Triple only) Why is it important to maintain levels of water and salt in the body?

A

Osmotic effects on cells meaning they don’t function normally

67
Q

(Triple only) Give three ways in which water is lost from the body

A

Urine, sweat, exhalation

68
Q

(Triple only) Give two ways in which water loss occurs which the body has no control over

A

Sweat (via skin) and exhalation (via lungs). Kidneys control how much water lost via urine

69
Q

(Triple only) Give two other components of sweat in addition to water

A

Ions and urea

70
Q

(Triple only) Name the process by which excess amino acids are dealt with, the organ involved, and the product made

A

Deamination in liver, product is ammonia (immediately converted to urea)

71
Q

(Triple only) What is the ammonia from deamination immediately converted into?

A

Urea

72
Q

(Triple only) Which organ maintains water balance in the body?

A

Kidney

73
Q

(Triple only) Name 3 substance that are selectively reabsorbed back into the blood by the kidneys

A

Glucose, some ions and water

74
Q

(Triple only) Name the process by which the kidneys remove substances from the blood, and the process by which some of them are then returned to the blood

A

Filtration, selective reabsorption

75
Q

(Triple only) Name the hormone involved in controlling the amount of water reabsorbed by the kidneys

A

ADH

76
Q

(Triple only) What effect does ADH have on the kidneys?

A

Increases the permeability of the kidney tubules

77
Q

(Triple only) Which organ releases ADH and which organ does it act on?

A

Released by pituitary gland, acts on kidneys

78
Q

(Triple only) Under what conditions is ADH released?

A

When blood is too concentrated

79
Q

(Triple only) Name two ways in which kidney disease can be treated

A

Organ transplant or dialysis

80
Q

(Triple only) What is dialysis?

A

Where blood is removed from the body to be artificially filtered via a machine

81
Q

(Triple only) Why does dialysis fluid contain glucose?

A

To prevent glucose leaving the blood via diffusion, and to ensure that water doesn’t move into the blood from the dialysis fluid by osmosis

82
Q

What overall effect do hormones have in reproduction?

A

Cause the development of secondary sexual characteristics

83
Q

Name the male reproductive hormone

A

Testosterone

84
Q

Name the female reproductive hormone

A

Oestrogen

85
Q

What is ovulation?

A

When an egg is released from the ovary in females (roughly once every 28 days)

86
Q

What is the main role of testosterone in males?

A

To stimulate sperm production

87
Q

Name the four hormones involved in control of the menstrual cycle

A

Oestrogen, progesterone, follicle stimulating
hormone (FSH), luteinising hormone (LH)

88
Q

What is the role of follicle stimulating hormone (FSH) in the menstrual cycle?

A

Causes maturation (ripening) of an egg in the ovary

89
Q

What is the role of luteinising hormone (LH) in the menstrual cycle?

A

Stimulates release of the egg

90
Q

What is the role of oestrogen and progesterone in the menstrual cycle?

A

Build up and maintain the uterus lining

91
Q

Where are oestrogen and progesterone produced?

A

In the ovaries

92
Q

Where are FSH and LH hormones produced?

A

Pituitary gland

93
Q

Name 4 hormonal methods of contraception

A

The pill, implant, injection, skin patch

94
Q

Name 2 barrier methods of contraception

A

condom (male and female), diaphragm

95
Q

How do barrier methods of contraception work?

A

Non-hormonal, prevent sperm reaching the egg

96
Q

How do hormonal methods of contraception work?

A

Prevent egg from maturing in the ovary (e.g. the pill inhibits FSH production)

97
Q

How do intrauterine devices prevent pregnancy?

A

Prevent implantation of an embryo in the uterus (may also release a hormone)

98
Q

Why are surgical methods not commonly used as a method of contraception in younger people?

A

They are permanent

99
Q

Which two hormones are in fertility drugs?

A

FSH and LH

100
Q

What is In vitro fertilisation (IVF)?

A

Eggs are removed from the woman and fertilised by sperm outside the body with the embryo then implanted into the uterus to help a woman become pregnant

101
Q

Give 3 problems with IVF treatment

A

Emotionally/physically stressful; low success rate; can lead to risky multiple births

102
Q

What is the role of thyroxine in the body?

A

Stimulates basal metabolic rate

103
Q

What effect does adrenaline have on the body?

A

Increases heart rate and boosts delivery of oxygen and glucose to the brain and muscles

104
Q

How is thyroxine controlled by negative feedback?

A

When thyroxine levels are low, TSH is released by the pituitary gland and stimulate thyroid gland to produce more thyroxine.

105
Q

(Triple only) Name the plant growth response to light

A

Phototropism

106
Q

(Triple only) Name the plant growth response to gravity

A

Gravitropism or geotropism

107
Q

(Triple only) Name the hormone involved in phototropism in plants and state it’s effect on cells

A

Auxin, causes cell elongation (on the shady side of the plant)

108
Q

(Triple only) Name the plant hormone involved in initiating seed germination

A

Gibberellins

109
Q

(Triple only) What is the role of ethene in plants?

A

Controls cell division and ripening of fruits

110
Q

(Triple only) Give 3 ways in which auxins can be used in agriculture or horticulture

A

Weedkillers; rooting powders; promoting growth in tissue culture

111
Q

(Triple only) How is ethene used in the food industry?

A

To control ripening of fruit during storage and transport

112
Q

(Triple only) Give 3 ways in which gibberellins can be used in agriculture and horticulture

A

End seed dormancy; promote flowering; increase fruit size

Biology AQA Triple (16 decks)

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