B3 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is your nervous system?

A

It detects changes in your external environment, processes it and responds to it accordingly

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

What are the 3 main stages to a nervous response?

A
  1. Change in environment
  2. Detecting the stimulus
  3. A response occurs from the effectors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a stimulus?

A

A change in the environment

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

What are the sensory receptors?

A

A group of cells that detects the stimulus

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

What are the effectors?

A

Muscles or glands

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

How do muscles respond to a impulse?

A

They contract which causes movement

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

How do glands respond to an impulse?

A

They release hormones

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

Where are receptors cells found?

A

In your sense organs

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

What do receptor cells do?

A

They change the stimulus into electrical impulses that travel along neurones to your central nervous system

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

What is your central nervous system (CNS) made up of?

A

Your brain and spinal cords - delicate nervous tissue so are protected by bones

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

What protects the brain?

A

The skull

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

What protects the spinal cord?

A

The vertebral column (backbone)

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

What are the receptor cells for you eyes?

A

Light

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

What is the stimulus for your eyes?

A

Light

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

What are the receptor cells for you tongue?

A

Taste

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

What is the stimulus for your tongue?

A

Chemical

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

What are the receptor cells for your skin?

A

Pressure and temperature

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

What are the stimuli for your skin?

A

Pressure and heat

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

What are the receptor cells for your nose?

A

Small and taste

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

What are the stimuli for your nose?

A

Chemical and chemical

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

What are the 3 types of neurones?

A

Sensory neurones
Relay neurones
Motor neurones

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

What do sensory neurones do?

A

Carry electrical impulses from receptor cells to the CNS

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

What do relay neurones do?

A

Carry electrical impulses from sensory neurones to motor neurones

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

What do motor neurones do?

A

Carry electrical impulses from the CNS to effectors

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

What are nerves made of?

A

Hundred or thousands of neurones

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

What are the steps involved in a nervous reaction?

A
  1. Stimulus
  2. Receptor cells
  3. Sensory neurone
  4. Spinal cord
  5. Brain
  6. Spinal cord
  7. Motor neurone
  8. Effector
  9. Response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How long does a nervous reaction usually take?

A

0.7 seconds

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

What is a coordinated response?

A

When you brain takes in a lot of information at the same time (all the time) and makes responses based on the information

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

What does a coordinated response usually end with?

A

A series of impulses being sent to different parts of the body to produce the required action

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

What a reflex action?

A

Faster, automatic, involuntary actions

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

What is different about a reflex action?

A

They miss out the brain so your body can react even faster

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

How long do reflex actions usually take?

A

0.2 seconds

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

What is an example of a reflex action?

A

Cutting your hand on broken glass - biceps contract to pull the arm away

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

What are the basic reflex actions?

A

Basic bodily functions:
Breathing
Heart rate
Digestion

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

What are the steps in a reflex action?

A
  1. Stimulus
  2. Receptor cells
  3. Sensory neurone
  4. Spinal cord
  5. Motor neurone
  6. Effector
  7. Response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is a reflex arc?

A

The nerve pathway that an impulse follows

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

Describe a reflex arc with steps (draw the flow diagram then add the sentences to make is specific).

A
  1. Stimulus - very hot saucepan
  2. Receptor cells - temperature receptors in skin
  3. Sensory neurone
  4. Spinal cord
  5. Motor neurone
  6. Effector - biceps muscle contracts
  7. Response - hand pulled away
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the cornea?

A

Transparent coating on the front of the eye

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

What does the cornea do?

A

Protects the eye, refracts light entering the eye

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

What is the pupil?

A

Central hole in the iris

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

What does the pupil do?

A

Allows light to enter the eye

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

What is the iris?

A

A colouring ring is muscle tissue

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

What does the iris do?

A

Alters pupil size by contracting or relaxing

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

What is the lens?

A

Transparent biconvex lens

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

What does the lens do?

A

Focuses light clearly onto the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What are the ciliary muscles?

A

Ring of muscle tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What do the ciliary muscles do?

A

Alters the shape of the lens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What are the suspensory ligaments?

A

Ligament tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What do the suspensory ligaments do?

A

Connects the ciliary body to the lens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is the optic nerve?

A

Nervous tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What does the optic nerve do?

A

Carries nerve impulses to the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What does refracts mean?

A

Changes direction of

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

How are images formed (step by step)?

A
  1. Cornea refracts incoming light rays - provides focus on the light
  2. Light passes pupil
  3. Light refracted again by lens - creates sharp image on retina
  4. Photoreceptors in retina produce nervous impulse (when expose to light)
  5. Impulse travels down the optic nerve to brain
  6. Brain interprets the impulses as a visual image
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What are photoreceptors?

A

Light sensitive cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What happens when your ciliary muscle contracts?

A

Your lens becomes more convex (fatter) - to focus on nearby objects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What happens when your ciliary muscle relaxes?

A

You lens becomes less convex (thinner) - to focus on distant objects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

How is short-sightedness caused?

A

A person’s lens being too strong or the eyeball is too long

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

How is long sightedness caused?

A

A person’s lens being too weak or by the eyeball being too short.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Why are images blurry when you are short sighted?

A

The light rays meet in front of the retina (not on it) making the image blurry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

How do you correct short-sightedness?

A

A CONCAVE lens bends the lights rays outwards before entering the eye.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Why is the image blurry in long sightedness?

A

The lights rays don’t meet on the retina (wider) so the image is blurred.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

How do you correct long-sightedness?

A

A CONVEX lens lens bends light rays inwards before they enter the eye.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What are the 2 types of photo preceptor cells in the retina?

A

Rods
Cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What do rods do?

A

Respond to light
Allow you to see in low light level
They aren’t responsive to different colours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What do cones do?

A

Respond to different colours
Different cone cells respond to red, blue and green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

How does colour blindness happen?

A

When people don’t have certain cones in their retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What is the most common form of colour blindness?

A

Red-green - people can’t distinguish between red and green light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Who does red-green colour blindness mainly affect?

A

Males - it is genetically inherited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What are the 5 main areas of the brain?

A

Cerebrum
Cerebellum
Medulla
Hypothalamus
Pituitary gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What does the cerebrum do?

A

Controls complex behaviour - learning, personality, memory and thought

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What does the cerebellum do?

A

Controls involuntary movements - posture and balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What does the medulla do?

A

Controls automatic actions - heart rate and breathing rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What does the hypothalamus do?

A

Regulates water balance and temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What does the pituitary gland do?

A

Stores and releases hormones that may regulate body functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What are the difficulties when investigating brain functions?

A

Patients must give consent for medical information to be shared
Many case studies need to be analysed to draw reliable conclusions
Several areas of the brain may be involved with a specific function
Some people believe animal testing is unethical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

How can you investigate brain function?

A

Placing electrodes inside the brain
CT scans (x-rays)
MRI scans - powerful magnets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What does placing electrodes in a brain do?

A

They transmit electrical impulses which result movement in different parts of the body - can link area of brain to body region it controls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

What are the systems in the mammalian nervous system?

A

Central nervous system (CNS)
Peripheral nervous system (PNS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What does the central nervous system consist of?

A

Brain
Spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

What does the peripheral nervous system consist of?

A

All the neurones that connect the CNS to the rest of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What is nervous system damage?

A

Damage to any part of your PNS or CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

What are examples of how you can get nervous system damage?

A

Injury - falling off a ladder
Disease - diabetes or cancer
A genetic condition - Huntington’s disease
Ingesting a toxic substance such as lead

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

Why is nervous system damage bad?

A

It prevents impulses from being passed effectively though the nervous system.

E.g - sport injury damage neurone - explain neurone function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What are some effects of nervous system damage?

A

Inability to detect pain
Numbness
Loss of coordination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What happens if you injure your peripheral nervous system?

A

It has a limited ability to regenerate but surgery is needed for major injuries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What can damage to the central nervous system lead to?

A

Loss of control of body conditions
Paralysis
Memory loss or processing difficulties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Why is it difficult to repair the spinal cord?

A

It consists of 31 pairs of nerves each containing nerve fibres, repairing 1 nerve without damaging others is extremely hard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

How could you treat a brain tumour?

A

Radiotherapy and chemotherapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

How could you treat damaged brain tissue?

A

Surgery to remove it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

How could you help brain function?

A

Deep brain stimulation - insertion of an electron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

What is different about repairing the CNS to the PNS?

A

The PNS has limited regeneration but the CNS cannot regenerate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

What are hormones?

A

Chemical messengers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

Where are hormones made?

A

The endocrine glans and secreted into the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

How are hormones transported around the body?

A

Blood transports the hormones in the plasma around the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

How fast are hormonal responses?

A

Fairly slow and long lasting (e.g puberty)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

What is homeostasis?

A

Keeping the conditions in your body constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

What does the hypothalamus and pituitary gland do?

A

Produce hormones that regulate production of other hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

What does the thyroid gland do?

A

Produce thyroxine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

Where is adrenaline produced?

A

Adrenal glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

Where is insulin produced?

A

The pancreas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

Where is oestrogen and progesterone produced?

A

Ovaries (females)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

What produces testosterone?

A

The testes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

How do hormones do their job?

A

The diffuse out the blood and bind to specific receptors for that hormone found on the membrane or cytoplasm of cells in the target organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

What are target cells?

A

The cells that bind to their specific hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

What do hormones do once bound?

A

They stimulate the target cells to produce a response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

What is the endocrine system?

A

The name given to all the endocrine glands and the hormones produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

What does the endocrine system do?

A

Controls and coordinates body processes with the nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

What do the endocrine system and nervous system both do?

A

Send messages around the body to provide information about any changes in the internal and external environment and how to respond to that.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

What are the attributes of nerves as a messaging system?

A

Very fast
Transport by electrical impulses through the axon of a nerve
Short acting duration
Target a precise area

110
Q

What are the attributes of hormones as a messaging system?

A

Slow
Transport in the blood
Duration is longer acting
Target a larger area

111
Q

What is the main function of thyroxine?

A

Regulates the body’s metabolic rate

112
Q

What is BMR?

A

The speed at which the body transfers energy from its chemical sores to perform functions

113
Q

How does thyroxine influence the metabolic rate?

A

By stimulating almost every tissue in the body to produce protein
By increasing the amount of oxygen that cells use

114
Q

What else does thyroxine do?

A

Is affects:
Heart rate
The rate at which calories are burned
Skin maintenance
Growth
Heat production
Fertility
Digestion

115
Q

Where are the adrenal glands?

A

Near the kidneys

116
Q

What is hypothyroidism?

A

An under-active thyroid where the thyroid gland doesn’t produce enough thyroxine

117
Q

How are most cases of hypothyroidism caused?

A

By the immune system attacking the thyroid gland and damaging it
By a result of treatment for an overactive thyroid

118
Q

What are some symptoms of hypothyroidism?

A

Tiredness
Weight gain
Depression
Dry skin/hair
Muscle aches
Being sensitive to the cold

119
Q

What is hyperthyroidism?

A

An overactive thyroid

120
Q

How can hypothyroidism be treated?

A

Taking tablets daily to increase thyroxine

121
Q

What are some symptoms of hyperthyroidism?

A

Weight loss
Increases heart rate
Anxiety
Excessive sweating
Tremors
Fatigue

122
Q

How can hyperthyroidism be treated?

A

Radioiodine treatment
Surgery to remove some of the thyroid

123
Q

What is the function of the thyroid gland?

A

To take iodine and convert in into thyroxine by combining idioine with the amino acid tyrosine

124
Q

What do the adrenal glands do?

A

Helps regulate:
Your metabolism
Immune system
Blood pressure
Response to stress

125
Q

What do the adrenal glands do at times if stress?

A

They secrete adrenaline which prepares the body for the fight or flight response

126
Q

What does adrenaline do?

A

Causes the body to respire faster
Increase the rate of ATP production
Increases rate of breathing
Increases heart rate
Diverts blood away to muscles

127
Q

What is negative feedback?

A

An important type of control used for homeostasis

128
Q

What is the negative feedback cycle?

A

Conditions in the body change
Change detected by a receptor
Corrective mechanisms activated by an effector
Conditions returned to set point
Corrective mechanisms switched off
Back to the beginning

129
Q

How are thyroxine levels controlled?

A

When more energy in needed, the hypothalamus causes the pituitary gland to release more TSH (thyroid stimulating hormone) which stimulates the thyroid gland to release thyroxine and vice Vera’s

130
Q

How are adrenaline levels controlled?

A

The brain signals the adrenal glands to secrete adrenaline and the signal stops when adrenaline is no longer needed

131
Q

What is the menstrual cycle?

A

A monthly cycle during which a woman’s body gets ready for pregnancy that lasts roughly 28 days

132
Q

What happens during the menstrual cycle?

A

The uterus lining starts to thicken, ready to receive a fertilised egg during which an egg starts to mature in one of the ovaries. 14 days ovulation happens and the lining of the uterus remains thick

133
Q

What happen if an egg is fertilised?

A

It may implant in the uterus lining to be protected and receive nutrients - The woman is now pregnant

134
Q

What happens in the egg isn’t fertilised?

A

The uterus lining and egg are removed form the body - known as a period or menstruation

135
Q

What is ovulation?

A

When the egg is released from the ovary

136
Q

What 4 hormones control the menstrual cycle?

A

FSH - follicle stimulating hormone
Oestrogen
LH - Luteinising hormone
Progesterone

137
Q

Where is FSH secreted from?

A

The pituitary gland

138
Q

What does FSH do?

A

It travels to the ovaries where it causes an egg to mature
Also stimulates ovaries to produce oestrogen

139
Q

What does oestrogen do?

A

Made and secreted by the ovaries that causes the uterus lining to build up.

140
Q

What happens as oestrogen levels rise?

A

They inhibit the production of FSH which prevents more than 1 egg from maturing
Stimulates the pituitary gland do release LH

141
Q

What does LH do?

A

When LH levels peak in the middle of a cycle, ovulation is triggered

142
Q

What does progesterone do?

A

Maintains the uterus lining and levels of this hormone stay high throughout pregnancy

143
Q

What does the blood oestrogen graph look like?

A

Two long lasting peaks

144
Q

What does the blood LH level graph look like?

A

Relatively low until ovulation - a large peak in the middle

145
Q

What does the blood FSH graph look like?

A

Increases as the end and beginning with a small peak in the middle

146
Q

What does the blood progesterone graph look like?

A

A large, long peak 3/4 of the way through the graph

147
Q

What is a contraception?

A

Any technique used to prevent pregnancy

148
Q

What are the different types of NON-HORMONAL contraceptives?

A

Condom
Diaphragm/cervical cap
IUD, coil

149
Q

How does a condom work?

A

Placed over penis or inside the vagina to prevent sperm from entering and it also prevents the spread of STIs

150
Q

How does a diaphragm/cervical cap work?

A

Inserted into vagina to cover cervix and prevents sperm from entering uterus x removed after 6 or more hours after intercourse but isn’t effective unless in combination with a spermicide

151
Q

How does an IUD work?

A

Inserted into uterus - releases copper which stops sperm from surviving in the uterus and fallopian tubes - can also prevent implantation of a fertilised ovum and works for 5-10 years

152
Q

What are examples of hormonal types of contraceptives?

A

Combined pill (oestrogen and progesterone)
Progesterone
Intrauterine system - IUS

153
Q

How does the combined pill work?

A

Prevents ovulation. Thickens mucus from the cervix, stopping sperm from reaching an ovum. Prevents implantiation of a fertilised egg into uterus wall

154
Q

How often do you have to take the combined pill?

A

Daily for 21 of the menstrual cycle

155
Q

How does a progesterone pill work?

A

Thicken mucus from the cervix, stopping sperms from reaching an ovum - also thins uterus lining preventing implantation and can prevent ovulation

156
Q

How often must the progesterone pill be taken?

A

Around the same time daily

157
Q

How does the IUS work?

A

Inserted into the uterus. Thicken mucus from the cervix, stopping sperms from reaching an ovum - also thins uterus lining preventing implantation and can prevent ovulation (same as progesterone pill)

158
Q

How long does the IUS last?

A

3-5 years

159
Q

How effective is the male condom?

A

98%

160
Q

How effective in the female condom?

A

95%

161
Q

How effective are the diaphragm and cap?

A

92 - 96%

162
Q

How effective are the hormonal methods of contraception?

A

Over 99%

163
Q

How effective is the IUD?

A

Over 99%

164
Q

What are some causes of infertility?

A

Blocked sperm ducts
Not enough sperm produced
Lack of mature eggs produced in the ovaries
Failure of the ovaries to release an egg
Blocked fallopian tubes

165
Q

Which hormone can be used to treat infertility and what is it known as?

A

FSH as an artificial fertility drug

166
Q

Why is FSH known as an artificial fertility drug?

A

It stimulates eggs to mature in the ovaries and triggers oestrogen production

167
Q

What does IVF stand for?

A

In vitro fertilisation

168
Q

How does IVF work?

A

It involves collecting sperm and giving the mother FSH and LH to ensure as many eggs mature as possible for them to be extracted - they are then fertilised outside the body

169
Q

What are the disadvantages of IVF?

A

No pregnancy
Multiple pregnancies

170
Q

What are the considerations around IVF?

A

It isn’t natural
Allows parents to conceive who otherwise wouldn’t be able to
Older parents can have children
Can result in multiple births
Very expensive
Allows young women to focus on careers and have children later in life

171
Q

What is tropism?

A

When plants detect stimuli in their environment and respond by growth in a particular position

172
Q

What is phototropism?

A

Growing towards the light so the plant can photosynthesise more, for more food, to grow faster and increase chance of survival

173
Q

What is gravitropism?

A

Growing in the same direction as gravity - mainly the roots so as to provide anchorage and be nearer to water

174
Q

What is auxin?

A

A plant hormone that enables a plant to row towards or away from a stimulus

175
Q

Where is auxin made?

A

Tips, shoot or roots of a pant

176
Q

What does auxin do?

A

Stimulates shoot cells to grow more but inhibits the growth of root cells

177
Q

How do plans respond to light?

A

Auxin moves to the side unaffected by light, increasing the length of that side so the shoot can bend towards light.
Auxin also gets evenly distributed if light falls evenly on a plant so the plant grows straight

178
Q

How do plants respond to gravity?

A

They produce auxin on the lower side originally but afterwards, it goes to the top left of the plant root to inhibit that growth so the plant grows towards gravity

179
Q

How are roots and auxin related?

A

The root grows more on the side with the least auxin

180
Q

What does ethene do for plants?

A

Causes plant fruits to ripen by stimulating the conversion of starch into sugar (ripe fruit taste sweeter than unripe)

181
Q

What are the different plant hormones?

A

Auxins
Ethene - only one that is a gas
Gibberellins

182
Q

What does gibberellins do?

A

Promotes growth, especially stem elongation
Also end the dormancy period of seeds and buds which allows shoots and flowers opening

183
Q

Why do many weed killers contain auxins?

A

Makes the weed grow to fast and this rapid, uncontrolled growth kills the plant

184
Q

How is auxin used to make identical plants/clones?

A

Cut off part of the plant and dip it into rooting powder (contains auxins) and plant it - few days later new roots anchor into soil and get nutrients

185
Q

How can one delay ripening?

A

Spraying auxin on it to delay ripening and allows harvest to be collected at the same time - can prevent fruit from dropping off trees early

186
Q

How can hormones be used to ripen fruit?

A

Ethan is prayed on fruit trees so their fruit ripen quicker which allows fruit to be ready earlier in the growing season

187
Q

How can seedless fruit be produced?

A

Auxins are applied to unpollinated flowers which then produces seedless fruit

188
Q

How are seeds produced in a fruit?

A

They are produced after a plant is pollinated by insects or the wind

189
Q

How are hormones used to control dormancy?

A

Gibberellins is prayed on seeds so the germinate during the winter because seeds usually remain dormant near the end of summer so they don’t die in the winter

190
Q

What is normal body temperature?

A

37 degrees Celsius as it is the optimum temperature for enzymes

191
Q

Why is being cold bad?

A

A low core temperature causes enzyme reaction to occur too slowly - respiration doesn’t release enough energy causing cells to die

192
Q

What temperature makes you at Rio’s of hypothermia?

A

Below 35 degrees Celsius

193
Q

What is it bad if your core temperature is too high?

A

Your enzymes may denature so body reactions cannot occur and you might die

194
Q

What is responsible for regulating body temperature?

A

The thermoregulatory centre in the brain

195
Q

What does the thermoregulatory centre depend on?

A

Signal from receptor cell in the skin (for external temp) and internal receptor cells (for blood temp)

196
Q

What happens when a change in temperature is detected?

A

The brain causes different parts of the body to respond by sending impulses to effector - homeostasis

197
Q

What happens when get too hot?

A

Body hairs lower so the hairs on the skin lie flat
Sweat glands produce sweat
Vasodilation

198
Q

How does body hairs lowering reduce body temperature?

A

It prevents an insulating layer of air being trapped around the body

199
Q

How does sweating reduce body temperature?

A

As water in sweat evaporates, energy is transferred by heating from your body to the environment, causing a reduction in temperature

200
Q

What is vasodilation?

A

When blood vessels supplying capillaries near the surface of the skin widen

201
Q

How does “vasodilation” reduce body temperature?

A

It increases blood flow through capillaries which increases heat loss by radiation

202
Q

What happens when you get too cold?

A

Body hairs rise
Sweat glands don’t produce sweat
Shivering
Vasoconstriction

203
Q

What is vasoconstriction?

A

Blood vessels supplying capillaries near the surface of your skin narrow

204
Q

How does “body hairs rising” cause you to get warmer?

A

It traps a layer of air close to the skin which insulates the body

205
Q

How does “vasoconstriction” cause you to get warmer?

A

It reduces blood flow through capillaries which reduces heat loss

206
Q

How does “shivering” cause you to get warmer?

A

Your muscles contract and relax quickly causing cells to respire more quickly which transfers extra energy by heating

207
Q

Why is high glucose (blood sugar level) bad?

A

If it is maintained over a long period of time, body systems can be damaged - especially nerves and blood vessels

208
Q

Why is low glucose (blood sugar levels) bad?

A

It can prevent cells from respiring effectively

209
Q

What does the pancreas do if blood sugar level is too high?

A

It releases insulin

210
Q

What does insulin do?

A

It travels in the blood to the liver which stimulates the liver to turn glucose into glycogen which is then stored in the liver - less glucose reduces blood sugar levels

211
Q

What does the pancreas do if blood sugar levels are too low?

A

It releases glucagon

212
Q

What does glucagon do?

A

Makes the liver change glycogen back into glucose which is then released into the blood to increase blood sugar levels

213
Q

What happens if you have type 1 diabetes?

A

Your body cannot produce insulin as the person’s own immune system has destroyed the pancreatic cells that make insulin

214
Q

When does type 1 diabetes usually start?

A

It normally begins in childhood

215
Q

How is type 1 diabetes controlled?

A

Regular injections of insulin

216
Q

What should a type 1 diabetic do?

A

Eat a balanced diet and exercise regularly

217
Q

What happens when you have type 2 diabetes?

A

You cannot effectively use insulin - the person’s cells do not produce enough insulin or the body doesn’t respond to it

218
Q

When does type 2 diabetes usually occur?

A

Usually occurs later in life and is linked to obesity

219
Q

How it type 2 diabetes controlled?

A

Regulating a person’s carbohydrate intake through their diet and matching this to their exercise levels- overweight people are encouraged to lose weight

220
Q

What are extreme ways of helping type 2 diabetes?

A

Drugs are used to stimulate insulin production or insulin injections are given

221
Q

What is excretion?

A

Removal of waste products

222
Q

What is lysis?

A

When there is too much water present, it moves into blood cells causing them to swell and burst

223
Q

What is too little water or too much solute bad?

A

Water will diffuse out of your blood cells, causing them to shrink

224
Q

What is urine?

A

A toxic solution containing excess water, urea, excess salts and other waste substances

225
Q

What do your kidneys do?

A

Filter urea out of your blood and produce urine constantly

226
Q

What does the bladder do?

A

Stores urine until you urinate

227
Q

What is the ureter?

A

A tube in which urine passes from the kidneys to the bladder

228
Q

What does the renal artery do (in terms of kidneys)?

A

It brings blood containing urea and other substances in solution to the kidney

229
Q

What does the renal vein do (in terms of the kidney)?

A

Carries blood away from the kidney after urea and other substances have been removed

230
Q

What is the urethra?

A

A tube in which urine passes to the outside of the body

231
Q

What is the first step of urine production?

A
  1. Small molecules (including water, glucose, urea and salts) pass into tubes inside the kidney - blood cells are too large and so remain in the capillaries.
  2. Selective reabsorption happens
232
Q

What is the second stage of urine production?

A

Kidneys put back any useful substances into the blood

233
Q

What is selective reabsorption?

A

When the kidneys put back any useful substances into the blood

234
Q

What are the useful substances that the kidneys out back into the blood?

A

All the glucose
Any salts the body needs
Some water

235
Q

Why does urine vary?

A

If you are short of water, kidneys produce little urine and water is saved for the body’s use which makes dark yellow urine and vice versa

236
Q

What is the capsule of a kidney?

A

Outer membrane of the kidney that helps to maintain the kidney’s shape and protect it from damage

237
Q

What is the cortex of a kidney?

A

The outer part of the kidney?

238
Q

What is the medulla of the kidney?

A

The inner part of the kidney

239
Q

What, inside the kidney, produced urine?

A

Microscopic tubules called nephrons

240
Q

Where is top of the nephron?

A

The cortex

241
Q

Where is the lower section of the nephron found?

A

The medulla

242
Q

What is the lower section of a nephron called?

A

The loop of Henlé

243
Q

How many nephrons do each kidney approximately contain?

A

1 million

244
Q

How does blood enter the kidney and from where?

A

Blood enters the kidney under high pressure from the renal artery which contains many branches, each of which leading to a glomerulus

245
Q

What does a glomerulus contain?

A

A knot of capillaries

246
Q

Why do the blood vessels narrow at the exit of the glomerulus?

A

To increase the blood pressure which forces small molecules out the capillary wall and into the bowman’s capsule.

247
Q

Why do proteins remain in the bloodstream?

A

It is too large to fit through the capillary walls

248
Q

How do the kidneys work (steps)?

A
  1. Blood enters the kidney under high pressure form renal artery which leads to a glomerulus from the many branches
  2. Blood vessels narrow at the exit of the glomerulus to force out small molecules in high pressure
  3. They go out the capillary wall into the bowman’s capsule
  4. Selective reabsorption happens through the nephron tubule
  5. The filtrate passes through the loop of Henlé and the collection ducts - regulate salt and water in the body
  6. Excretion occurs and the urine collects in the collecting duct which travels to the bladder before leaving the body
249
Q

How does the body control how much urine is produced?

A

The hypothalamus detects the water potential of blood as it passes the brain and it responds by secreting the amount of ADH needed.

250
Q

What does ADH stand for?

A

Anti-diuretic hormone

251
Q

Where does ADH get secreted from?

A

The pituitary gland

252
Q

What does ADH do?

A

It travels in the bloodstream to the kidney where it makes the walls of the collecting ducts more permeable to water which means more water is reabsorbed into the body

253
Q

What happens if water potential is too low?

A

More ADH is produced - more water is reabsorbed from the nephron into the blood stream - less water is lost from the body

254
Q

What does an INCREASED amount of ADH mean for urine produced?

A

A small volume of concentrated urine is produced

255
Q

What happens in blood water concentration is too high?

A

Less ADH is produced - less water is reabsorbed from the nephron into the blood stream - more water is lost

256
Q

What are some examples of when you would need more water?

A

When you take part in strenuous exercise
When you are exposed in high temperatures

257
Q

What is lost from the body when you sweat?

A

Water
Salts

258
Q

How does the body respond to a lack of water?

A

Your body triggers the thirst response
An impulse is sent to your brain which informs you to take on more fluids
You become dehydrated

259
Q

What is dehydration?

A

A condition when you have not taken enough water into your body

260
Q

What are some symptoms of dehydration?

A

Passing of dark, concentrated urine
Headaches and dizziness
A lack of energy

261
Q

What happens if a person is dehydrated for a longer period of time?

A

The kidneys and liver may suffer permanent damage and eventually you may die

262
Q

How does the body respond to too much water”

A

Kidneys produce more dilute urine
Water will move by osmosis into your cells

263
Q

Why is it bad to consume a large amount of water rapidly?

A

Water moves into your cells by osmosis, causing them to burst
Concentration of sodium in blood plasma drops

264
Q

What are extreme causes of water moving into your cells by osmosis?

A

Muscle cramping, confusion, seizures
When water moves to brain cells, it can cause death.

265
Q

What does a hypertonic drink contain?

A

High levels of glucose and salts

266
Q

What does a hypotonic drink contain?

A

Low levels of glucose and salrs

267
Q

What does an isotonic drink contain?

A

Ion concentrations equal to those in blood plasma

268
Q

What type of athlete would use a hypotonic drink?

A

Endurance athletes as the drink will give them the electrolytes needed while running

269
Q

What type of athlete would drink hypertonic drinks?

A

Athletes that require rapid glycogen replenishment - body building or sprinters and the drinks have more carbs

270
Q

What type of athlete would use an isotonic drink?

A

It rehydrates you rapidly so football players or tennis players