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PMT Biology Flashcards > Structure and Function Of Living Organisms > Flashcards

Structure and Function Of Living Organisms Flashcards

1
Q

What is a tissue?

A

A group of cells working together to carry out a specific function

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2
Q

What is an organ?

A

A group of tissues working together to carry out a specific function

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3
Q

Define organ system?

A

A group of organs working together to carry out a specific function

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4
Q

Name 5 parts of an animal cell

A

Nucleus
Mitochondria
Ribosomes
Cell membrane
Cytoplasm

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5
Q

Name 8 parts of a plant cell

A

Nucleus
Mitochondria
Ribosomes
Cell membrane
Cytoplasm
Permanent vacuole
Chloroplasts
Cell wall

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6
Q

State 2 function of the nucleus

A

Controls the cell
Contains genetic material in the form of chromosomes

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7
Q

What is the function of the cytoplasm?

A

Site of chemical reactions

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8
Q

What is the function of the mitochondria?

A

They are the site of aerobic respiration

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9
Q

What are the function of ribosomes?

A

Site of protein synthesis

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10
Q

What is the function of the cell wall and what is it made of?

A

Provides strength and support. It’s made of cellulose

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11
Q

What is the function of the permanent vacuole and what does it contain?

A

It supports the cell and contains cell sap

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12
Q

What is the function of chloroplasts?

A

Site of photosynthesis

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13
Q

What is the function of the cell membrane?

A

Controls what enters and leaves the cell
Separates the cell from its environment

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14
Q

What is differentiation?

A

The process by which cells become specialised

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15
Q

What are stem cells?

A

Unspecialised cells that can differentiate into lots of different types of cells

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16
Q

Give 3 advantages of using stem cells in medicine

A

Can treat paralysis
Have the possibility to cure degenerative diseases like Parkinson’s
Whole new tissues or organs can be grown that can be used to test drugs on

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17
Q

Give 3 disadvantages of using stem cells in medicine

A

Using embryonic stem cells can raise ethical issues
Expensive
Long term side effects are unknown

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18
Q

What chemical elements are present in carbohydrates?

A

Carbon, hydrogen, oxygen

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19
Q

What chemical elements are present in lipids?

A

Carbon, hydrogen and oxygen

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20
Q

What chemical elements are present in proteins?

A

Carbon, hydrogen, oxygen, nitrogen and sulfur

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21
Q

What are complex carbohydrates made up of?

A

Simple sugars

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22
Q

What are proteins made up of?

A

Amino acids

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23
Q

What are lipids made up of?

A

Glycerol and fatty acids

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24
Q

What are enzymes?

A

Biological catalysts that increase the rate of metabolic reactions

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25
Q

What 4 factos affect enzyme function?

A

Temperature
pH
Substrate concentration
Enzyme concentration

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26
Q

Describe the effect of temperature of the rate of an enzyme-controlled reaction

A

As the temperature increases, so does the rate of reaction
Once the temperature exceeds the optimum, the enzyme denatures and the rate of reaction decreases

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27
Q

Why does the rate of an enzyme-controlled reaction increase when the temperature increases?

A

As the temperature increases the particles have more kinetic energy
This increases the chance of collisions between molecules being successful and leading to a reaction

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28
Q

If temperature increases above the optimum, how does this affect enzyme function?

A

The active site will be distorted as the enzyme denatures and so the active site will no longer fit the substrate

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29
Q

Describe the effect of pH on the rate of an enzyme-controlled reaction?

A

The rate of an enzyme catalysed reaction is fastest at the optimum pH
If the pH is too high/low the enzyme will work less efficiently and the active site may be denatured at extremes of pH

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30
Q

Define diffusion

A

The net movement of molecules from an area of high concentration to an area of low concentration down a concentration gradient

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31
Q

How does temperature affect the rate of diffusion?

A

As the temperature increases, so does the rate of diffusion as the particles have more kinetic energy and move faster

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32
Q

How does the concentration gradient affect the rate of diffusion?

A

The greater the concentration gradient the faster the rate of diffusion

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33
Q

How does the surface area of the membrane affect the rate of diffusion?

A

As the surface area increases so does the rate of diffusion as there is more space for the particles to move through

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34
Q

Define osmosis

A

The net movement of water molecules from a high water potential to a low water potential down the water potential gradient across a partially permeable membrane

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35
Q

Define active transport

A

The movement of molecules from a low concentration to a high concentration against their concentration gradient using energy

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36
Q

What is photosynthesis?

A

The process where some organisms are able to turn light energy into chemical energy

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37
Q

What type of organisms use photosynthesis to make their own food?

A

Producers

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38
Q

What type of reaction is photosynthesis?

A

Endothermic

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39
Q

Where does photosynthesis take place?

A

In the chloroplasts

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40
Q

What is the word equation for photosynthesis?

A

Carbon dioxide + water = glucose + oxygen

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41
Q

Explain the effect of temperature on the rate of photosynthesis

A

As temperature increases, so does the rate of photosynthesis
Once the temperature exceeds the optimum, the rate of photosynthesis decreases as enzymes begin to denature

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42
Q

Explain the effect of light intensity on the rate of photosynthesis

A

As the light intensity increases, so does the rate of photosynthesis

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43
Q

Explain the effect of carbon dioxide concentration on the rate of photosynthesis

A

As the concentration of carbon dioxide increases, so does the rate of photosynthesis

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44
Q

What is a limiting factor?

A

A factor that limits the rate of reaction when there is not enough of it

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45
Q

Give 3 ways leaves are adapted for efficient photosynthesis

A

They are thin so diffusion distance is short
The spongy mesophyll layer has lots of air spaces for efficient gas exchange
Palisade mesophyll cell have lots of chloroplasts for photosynthesis

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46
Q

What are mineral ions used for in a plant?

A

Growth

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47
Q

Give 2 common ions in plants

A

Magnesium and nitrates

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48
Q

What are magnesium ions used for in plants?

A

Used in chlorophyll

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49
Q

What are nitrate ions used for in organisms?

A

Amino acids

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50
Q

Why is a balanced diet important?

A

The body needs different substances in different proportions to function properly, too much/little of different things can be harmful

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51
Q

What 7 groups are needed for a balanced diet?

A

Carbohydrates, proteins, lipids, vitamins, minerals, water and dietary fibre

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52
Q

What are the functions of carbohydrates in the diet?

A

Carbohydrates are the bodys main source of energy

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53
Q

What are the functions of proteins in the body?

A

Proteins can have structural or metabolic roles in the body and are used as hormones, enzymes, antibodies

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54
Q

What are the functions of lipids in the body?

A

Energy storage, cell membranes, buoyancy and insulation

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55
Q

What is vitamin A used for?

A

Keeping skin healthy, improved vision in the dark and strengthening the immune system

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56
Q

What is vitamin C used for?

A

Growth and repair

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57
Q

What is vitamin D used for?

A

The absorption of calcium

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58
Q

What is calcium used for in the body?

A

Strengthens bones and teeth

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59
Q

What is iron used for in the body?

A

Used in haemoglobin to transport oxygen in the blood

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60
Q

What is water used for in the body?

A

Reaction medium, temperature control and transport

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61
Q

What is dietary fibre used for?

A

Helps food pass through the digestive system

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62
Q

How does energy requirements change based on how active you are?

A

The more active a person is, the greater their energy requirement

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63
Q

How does energy requirements change based on age?

A

Adults generally require more energy than children

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64
Q

What is the alimentary canal?

A

The complete tube that food passes through as it passes through the body

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65
Q

What is the difference between the alimentary canal and the digestive system?

A

The alimentary canal involves the tubes that the food passes through whereas the digestive system also includes digestive glands

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66
Q

Describe the passage of food through the alimentary canal

A

Mouth -> oesophagus -> stomach -> small intestine -> large intestine -> rectum

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67
Q

What is the function of the mouth?

A

To chew and break down food
To secrete digestive enzymes

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68
Q

What is the oesophagus?

A

The tube that carries food from the mouth to the stomach

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69
Q

What does the stomach do?

A

The stomach is a muscular sac containing acid that pummels the food and breaks it down further

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70
Q

What role does the pancreas play in digestion?

A

The pancreas secretes digestive enzymes into the small intestine

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71
Q

What are the two parts of the small intestine?

A

Duodenum and ileum

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72
Q

What is the function of the duodenum?

A

It receives food directly from the stomach and uses enzymes and chemical digestion to break the food down

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73
Q

What is the function of the ileum?

A

Most nutrients are absorbed from the food in the ileum into the blood

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74
Q

How is the ileum adapted to absorption?

A

The ileum is lined with villi which provide a large surface area for reabsorption

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75
Q

How are villi adapted for absorption?

A

Thin walls
Large surface area
Good blood supply close to the surface

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76
Q

What is the function of the large intestine?

A

Water is reabsorbed into the blood in the large intestine

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77
Q

What is the function of the rectum?

A

Storing faeces before egestion

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78
Q

How does peristalsis work to push food through the gut?

A

Muscles contract in a wave like fashion which pushes food along

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79
Q

What enzymes break down starch into glucose?

A

Maltese and amylase

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80
Q

What group of enzymes break down proteins down into amino acids?

A

Proteases

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81
Q

What group of enzymes break down lipids into glycerol and fatty acids?

A

Lipases

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82
Q

What does bile do?

A

Neutralises the stomach acid and provides alkaline conditions for the digestive enzymes in the small intestine
Emulsifies fats

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83
Q

Where is bile produced?

A

The liver

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84
Q

Where is bile stored?

A

The gallbladder

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85
Q

What is the purpose of respiration?

A

To produce energy in the form of ATP from larger molecules

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86
Q

What type of reaction is respiration?

A

An exothermic reaction

87
Q

When does aerobic respiration take place?

A

When there is plenty of oxygen available

88
Q

When does anaerobic respiration take place?

A

When there is no oxygen available

89
Q

What does anaerobic respiration in animals produce?

A

Lactic acid and energy

90
Q

Which type of respiration produces more ATP?

A

Aerobic respiration produces 36ATP compared to anaerobic respiration which produces only 2ATP

91
Q

What is the oxygen debt?

A

The extra oxygen that is needed to break down the lactic acid formed in anaerobic respiration

92
Q

What gas do plants need to take in for aerobic respiration?

A

Oxygen

93
Q

What gas do plants need to remove from respiration?

A

Carbon dioxide

94
Q

What gas do plants need to take in for photosynthesis?

A

Carbon dioxide

95
Q

What gas do plants need to remove from photosynthesis?

A

Oxygen

96
Q

Give 3 adaptations of leaf tissues for gas exchange

A

Stomata allow diffusion of gases in and out of the plant
Thin to shorten diffusion distance
Air spaces in the spongy mesophyll layer allow gases to diffuse

97
Q

Why don’t plants keep the stomata open permanently?

A

To reduce water loss

98
Q

Why do plants release more carbon dioxide compared to oxygen at night?

A

Respiration continues during the night whereas photosynthesis doesn’t
Respiration releases carbon dioxide and photosynthesis releases oxygen

99
Q

Describe the general structure of the lungs

A

Trachea branches into two bronchi
Bronchi branch into bronchioles
Bronchioles terminate into alveoli

100
Q

Describe the structure of an alveolus

A

Small sacs with capillaries around them
Contain a surfactant so walls don’t stick together and so gases can dissolve to help diffusion

101
Q

What is the purpose of the pleural membrane?

A

Covers the lungs, reduces friction and keeps the lungs moist

102
Q

What are the intercostal muscles?

A

A group of muscles found between the ribs that are involved in breathing by changing the size of the thorax

103
Q

How do the diaphragm and intercostal muscles work together during expiration?

A
  • diaphragm relaxes and moves up
  • external intercostal muscles relax
  • volume in the thorax decreases and air moves out
104
Q

How do the diaphragm and intercostal muscles work together during inspiration?

A
  • diaphragm contracts and moves down
  • external intercostal muscles contract
  • volume in the thorax increases and air moves in
105
Q

Give 3 health issues caused by smoking

A

Cancer
Bronchitis
Coronary heart disease

106
Q

How does smokers cough happen?

A

Cilia on cells lining the trachea waft mucus containing dirt out of the lungs
Smoking can kill cells lining the trachea
A build-up of mucus in the lungs can cause people to develop smokers cough

107
Q

Why can unicellular organism rely on diffusion alone?

A
  • they have a large surface area to volume ratio due to their size
  • they have low metabolic demands
108
Q

What does the phloem transport?

A

Sugars like sucrose

109
Q

What direction does the phloem transport sugars?

A

The phloem transports sugars up and down the plant from source to sink

110
Q

What does the xylem transport?

A

The xylem transports water and minerals

111
Q

What direction does the xylem transport water and minerals?

A

Up the plant (from the roots to the leaves)

112
Q

How are root hair cells adapted to their function?

A
  • long root hair extension to increase surface area for uptake
  • thin membrane to decrease diffusion distance
113
Q

What are the benefits of transpiration?

A
  • the stream of water cools the plant
  • the water helps support the plant
  • plant has a constant water supply for photosynthesis
114
Q

How is the xylem adapted to transport water?

A
  • its waterproofed using lignin
  • the cells have no organelles so there’s more space for water
115
Q

What is transpiration?

A
  • water is lost through the stomata
  • more water is drawn up to replace the lost water
116
Q

What is the transpiration stream?

A

The flow of water through a plant

117
Q

How does temperature affect the rate of transpiration?

A
  • as the temperature increases, so does the transpiration rate
  • molecules have more kinetic energy and evaporation happens faster
118
Q

How does light intensity affect the rate of transpiration?

A
  • the brighter the light, the more stomata are open and the rate of photosynthesis increases, which both decrease amount of water in the plant
  • rate of transpiration increases
119
Q

How does wind speed affect the rate of transpiration?

A

The faster the wind speed, the faster the water is moved away from the plant, creating a steeper gradient and increasing the transpiration rate

120
Q

What is translocation?

A

The movement of sugars up or down the phloem from source to sink using energy

121
Q

Name 4 components of the blood

A
  • red blood cells
  • white blood cells
  • platelets
  • plasma
122
Q

What is the function of platelets?

A

Platelets are small fragments of cells that are involved in blood clotting

123
Q

What are 2 benefits of blood clotting?

A
  • prevents the entry of microorganisms
  • prevents blood loss
124
Q

How are red blood cells adapted to their function?

A
  • contain haemoglobin to carry oxygen
  • biconcave shape to maximise surface area and allow them to squeeze through capillaries
  • no nucleus to maximise space for haemoglobin
125
Q

What is the purpose of plasma?

A

Plasma is the liquid part of the blood and its purpose is to act as a transport medium to transport carbon dioxide, hormones, nutrients and waste products

126
Q

What is the function of white blood cells?

A

White blood cells are involved in the immune response

127
Q

What is a pathogen?

A

A disease-causing microorganism

128
Q

How does the body respond to a pathogen

A
  • lymphocytes can produce antibodies that are specific to the antigens on the pathogen
  • phagocytes engulf the pathogen
129
Q

How do vaccines work?

A
  • dead/inactive pathogens are injected into the body
  • the body produces antibodies against the pathogen
  • memory cells are also created to provide long term immunity
130
Q

Describe the double circulatory system in mammals

A

The heart pumps blood to the lungs, the oxygenated blood returns to the heart and is then pumped around the body

131
Q

What is the difference in function between veins, arteries, and capillaries?

A
  • arteries carry blood away from the heart
  • veins carry blood towards the heart
  • capillaries flow close to tissues for gas exchange
132
Q

Describe the structure of arteries

A

They have thick walls made of muscle and elastic tissue and a small lumen to transport blood under high pressure

133
Q

Describe the structure of capillaries

A

They have thin walls about one cell thick to allow for the easy exchange of substances at the tissues

134
Q

Describe the structure of veins

A

Veins have less muscle and elastic tissue than arteries and they have a larger lumen as the blood is at lower pressure, they also have valves to prevent backflow

135
Q

Describe the blood flow through the right side of the heart

A
  • deoxygenated blood flows into the right atrium from the vena cava
  • this blood passes through the right AV valve into the right ventricle
  • the blood is then pumped out of the heart to the lungs through the right SL valve and into the pulmonary artery
136
Q

Describe the blood flow through the left side of the heart

A
  • blood enters into the left atrium from the pulmonary vein
  • the blood is then pumped through the left AV valve into the left ventricle
  • the blood is then pumped out through the left SL valve and into the aorta
137
Q

What is the name of the wall that separates the right and left sides of the heart?

A

The septum

138
Q

What is the name of the artery that supplies the heart tissue with blood?

A

The coronary artery

139
Q

What type of muscle is the heart made of?

A

Cardiac muscle

140
Q

Why is the wall of the left ventricle thicker than the wall of the right ventricle?

A

The left ventricle has to pump blood a further distance around the whole body so the blood needs to be under a higher pressure

141
Q

What does adrenaline do to the heart rate?

A

Adrenaline increases the heart rate as it triggers the ‘fight or flight’ reflex

142
Q

What parts of the body (apart from the heart) does adrenaline affect?

A
  • dilates the pupils
  • increases breathing rate
143
Q

Why does heart rate increase during exercise?

A
  • more muscle movement requires more energy from respiration
  • the muscle tissues need to be provided with a supply of oxygen to carry out respiration and so the heart needs to pump faster to provide the oxygen
144
Q

What is coronary heart disease?

A

When the artery providing the heart tissue with blood becomes blocked

145
Q

What are 3 common risk factors for coronary heart disease?

A
  • smoking
  • poor diet
  • lack of exercise
146
Q

What waste gases do plants produce and what processes produce them?

A
  • oxygen from photosynthesis
  • carbon dioxide from respiration
147
Q

What is the function of the kidneys?

A
  • to regulate the volume and concentration of urine
  • to remove waste and regulate body water content
148
Q

Describe the general structure of a kidney

A
  • contains a cortex and a medulla
  • renal artery carries blood to the kidney
  • renal vein carries blood away from the kidney
  • each kidney contains many nephrons
  • ureter carries fluid from the kidneys to the bladder
149
Q

What are examples of waste products produced in the body

A
  • urea
  • carbon dioxide
  • excess salt and water
150
Q

Name 3 excretory organs?

A
  • lungs
  • kidney
  • skin
151
Q

What are the 4 roles of the kidney?

A
  • filtration
  • selective reabsorption
  • excretion
  • osmoregulation
152
Q

What does the ureter do?

A

Carries urine from the kidneys to the bladder for excretion

153
Q

What are the 5 main parts of a kidney nephron?

A
  • glomerulus
  • proximal convoluted tubule
  • loop of henle
  • distal convoluted tubule
  • collecting duct
154
Q

What is the difference between the ureter and the urethra?

A
  • ureter: leads from the kidneys to the bladder
  • urethra: leads from the bladder out of the body
155
Q

How does ultrafiltration work in the bowman’s capsule?

A
  • blood vessel leading to the glomerulus is wider than the one leading away which increases the pressure of the blood as it travels along
  • small items in the blood are squeezed out under this high pressure
156
Q

State 4 components of glomerular filtrate

A
  • urea
  • salts
  • water
    -glucose
157
Q

What’s the purpose of selective reabsorption?

A

To prevent the excretion of useful substances like glucose

158
Q

What does ADH stand for?

A

Antidiuretic hormone

159
Q

When is ADH released?

A

When the body lacks water

160
Q

How does ADH affect the collecting duct?

A

ADH makes the collecting duct more permeable to water so that more water is reabsorbed from the filtrate

161
Q

What happens in the body when dehydration is detected?

A
  • thirst signals activated
  • more ADH is released so more water is retained by the kidneys
162
Q

What happens in the body when overhydration is detected?

A
  • less ADH released
  • dilute urine produced
  • salts retained
163
Q

What are 3 components of urine?

A
  • water
  • urea
  • ions
164
Q

Define homeostasis

A

Maintaining a constant internal environment despite external change

165
Q

What are 3 conditions which need to be controlled in the body

A
  • temperature
  • water levels
  • blood glucose concentration
166
Q

What are the 3 main parts to a coordinated response?

A
  • stimulus
  • receptor
  • effector
167
Q

What does auxin trigger?

A

Auxin triggers growth of the main them of the plant and inhibits growth of side shoots

168
Q

What is phototropism and which part of a plant is positively phototrophic?

A

Phototropism is the growth of a plant towards a light source.
Shoots are positively phototrophic

169
Q

What is geotropism and which part of a plant is positively geotrophic?

A

Geotropism is the growth of a plant towards the pull of gravity.
The roots are positively geotrophic

170
Q

How does auxin cause shoots to be positively phototrophic?

A
  • auxin collects on the shaded side
  • auxin promotes cell growth
  • shoot curves towards the light
171
Q

Give 3 differences between nervous and hormonal communication

A
  • nervous communication uses nerve cells and impulses whereas hormones are secreted by glands and travel in the blood
  • nervous communication is generally much faster than hormonal communication
  • hormonal communication usually brings about longer-lasting responses than nervous communication
172
Q

What is the difference between the central nervous system and the peripheral nervous system?

A

The central nervous system is the brain and the spinal cord.
The peripheral nervous system is every other part of the nervous system.

173
Q

How is an impulse transmitted between two neurones?

A
  • the impulse reaches the end of one neurone
  • a neurotransmitter is released and it diffuses across the gap
  • a new impulse is triggered in the next neurone
174
Q

What is a stimulus?

A

A change in the environment

175
Q

What type of neurone connects a receptor to the CNS?

A

A sensory neurone

176
Q

What is an effector?

A

A part of the body that brings about the response to a stimulus like a muscle or a gland

177
Q

What type of neurone connects the CNS to an effector?

A

A motor neurone

178
Q

Describe a reflex arc

A
  • a stimulus is detected by a receptor
  • an impulse is passed along a sensory neuron to the CNS
  • an impulse is passed along a motor neuron to an effector
  • an effector brings about the response
179
Q

Describe the sequence of events involved in removing a hand away from a hot flame

A
  • thermoreceptors in the hand detect the heat of the flame
  • an impulse is sent along a sensory neurone
  • the impulse passes through relay neurones in the CNS
  • the impulse then passes along a motor neurone and triggers the muscles in the arm to move the hand away
180
Q

What is the cornea and what is its function?

A

The transparent layer in front of the eye that protects the eye from damage

181
Q

What is the iris and what is its function?

A

The coloured ring around the pupil that controls its diameter

182
Q

What is the pupil and what is its function?

A

The pupil is the hole in the middle of the iris that lets light into the eye

183
Q

What is the optic nerve and what is its function?

A

The nerve coming out of the back of the eye that sends signals to the brain

184
Q

What is the function of the lens?

A

The lens focuses the light rays onto the retina

185
Q

What is the retina and what is its function?

A

The retina is the back part of the eye and it converts visual stimuli into electrical impulses

186
Q

What do the ciliary body and suspensory ligaments do?

A

They control the shape of the lens

187
Q

How does the eye focus on near objects?

A
  • ciliary muscles contract and suspensory ligaments relax, causing the lens to thicken
  • thicker lens causes the light to refract more
188
Q

How does the eye focus on far away objects?

A
  • ciliary muscles relax and suspensory ligaments stretch, which makes the lens thinner
  • thinner lens means the light refracts less
189
Q

How does the eye respond to bright light?

A

The iris contracts, making the pupil smaller and letting in less light

190
Q

How does the eye respond to a lack of light?

A

The iris relaxes which makes the pupil larger and lets in more light

191
Q

Why does the temperature need to be controlled?

A

To provide a suitable environment for enzymes so they can work fastest at their optimum temperature

192
Q

Give 2 processes involving the skin that cools the body down

A

Sweating - cools the body by evaporation
Vasodilation - allows blood flow to flow closer to the surface of the skin where it can cool

193
Q

Describe the process of vasodilation

A
  • the body detects a rise in temperature
  • blood vessels supplying the capillaries at the skins surface dilate
  • more blood flows closer to the skin where it can cool
194
Q

Give 3 processes that work to keep the body warm

A
  • vasoconstriction
  • shivering
  • erection of the hairs on the skin
195
Q

Describe the process of vasoconstriction

A
  • the body detects a drop in temperature
  • blood vessels supplying the capillaries at the skins surface constrict
  • less blood flows closer to the skins surface so less heat is lost to the surroundings
196
Q

What are hormones?

A

Chemical messengers that are secreted by glands of the endocrine system into the bloodstream

197
Q

What does insulin do in the body?

A

Decreases blood glucose concentration

198
Q

Where is insulin secreted from?

A

Pancreas

199
Q

What does testosterone do?

A
  • main male sex hormone
  • involved in growth of testes and penis
  • triggers puberty in males
200
Q

Where is testosterone secreted from?

A

The testes

201
Q

When is adrenaline secreted?

A

During times of anxiety, fear or stress

202
Q

Where is adrenaline released from?

A

Adrenal glands

203
Q

Give 3 effects of adrenaline in the body

A
  • increases heart and breathing rate
  • increases blood glucose concentration
  • dilates the pupils
204
Q

What does oestrogen do?

A

Causes the uterus lining to thicken

205
Q

Where is oestrogen secreted from?

A

Ovaries

206
Q

What hormone does oestrogen inhibit?

A

Follicle stimulating hormone

207
Q

What does progesterone do?

A

Maintains the womb lining

208
Q

Where is progesterone secreted from?

A

Ovaries

209
Q

What hormone does progesterone inhibit?

A

Follicle stimulating hormone

210
Q

What does follicle stimulating hormone do?

A

Stimulates the follicle to mature and release oestrogen

211
Q

What does luteinising hormone do?

A

Causes the releases of an egg from follicles

212
Q

Where is FSH secreted from?

A

Pituitary gland

213
Q

Where is LH secreted from?

A

Pituitary gland

214
Q

Where is ADH secreted from?

A

Pituitary gland

PMT Biology Flashcards (5 decks)

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