Biology Gcse Flashcards B3

Front 1

Osmosis

Back 1

Diffusion of water from a dilute to a more concentrated solution

Front 2

What can pass through a partially permeable membrane?

Back 2

Water molecules

Front 3

Most soft drinks contain

Back 3

Water, sugar and ions

Front 4

Why do sports drinks contain sugar?

Back 4

To replace the sugar used up during exercise

Front 5

Why do sports drinks contain ions and water?

Back 5

To replace those that are lost from sweat during exercise

Front 6

What happens if during exercise we do not replace the lost sugars, water and ions?

Back 6

Our cells will not work as efficiently

Front 7

Active transport

Back 7

When substances are absorbed against the concentration gradient which requires energy from respiration

Front 8

How does having a large surface area make exchanging materials more effective?

Back 8

More cells are exposed so that they can absorb more substances

Front 9

How does being thin make exchanging materials more effective?

Back 9

This makes the distance path shorter and so will take less time

Front 10

What traits in animals help make exchanging materials more effective? (2)

Back 10

Having an efficient blood supply
Being ventilated

Front 11

The size and complexity (number of cells) increases

Back 11

The difficulty of exchanging materials

Front 12

The surface are of the lungs is increased by

Back 12

Alveoli

Front 13

The surface area of the small intestine is increased by

Back 13

Villi

Front 14

Villi absorbs the products of digestion by

Back 14

Active transport

Front 15

How does the breathing system work?

Back 15

The oxygen from the air taken in from the lungs uses red blood cells to diffuse into the bloodstream
Carbon dioxide made from respiration diffuses out of the bloodstream back into the air

Front 16

Ventilation

Back 16

The movement of air into and out of the lungs

Front 17

What happens during inhalation?

Back 17

Oxygen moves into the lungs
The intercostal muscles move the ribcage up and out so that the diaphragm contracts
This increases the volume in the thorax - lowering the pressure inside in comparison to outside the body, making air rush in

Front 18

What happens during exhalation?

Back 18

Carbon dioxide moves out of the lungs
The intercostal muscles move the ribcage down and in so that the diaphragm relaxes
This decreases the volume in the thorax - increasing the pressure inside in comparison to outside the body, making it rush out

Front 19

How does carbon dioxide enter the leaves of a plant?

Back 19

Through diffusion

Front 20

What is the advantage of root hairs?

Back 20

Larger surface area for absorbing more water and mineral ions

Front 21

How is the surface area of leaves increased?

Back 21

Flattened shape and air spaces

Front 22

Why do plants have stomata?

Back 22

To obtain carbon dioxide from the atmosphere and remove oxygen produced in photosynthesis

Front 23

Where is water vapour lost in plants?

Back 23

In the stomata of the leaves

Front 24

In what conditions is water evaporated most in plants?

Back 24

Hot - because the water will gain enough kinetic energy to evaporate
Dry - as there is more water on the plant than in the air (diffusion)
Windy - since it would simply be carried off

Front 25

What do plants do to prevent wilting?

Back 25

The stomata closes when more water is being lost than what is being gained to replace it

Front 26

What controls the size of the stomata?

Back 26

Guard cells

Front 27

Describe the function and structure of the heart

Back 27

The heart is an organ which pumps blood around the body
It is made up of left and right atria and ventricles
The wall of the heart is made of muscle tissue

Front 28

Arteries

Back 28

Transport blood away from the heart
Have thick walls containing elastic fibresin order to carry the blood under high pressure

Front 29

Veins

Back 29

Transport blood to the heart
Have thinner walls with valves because it carries blood under low pressure so it needs to avoid backflow

Front 30

Coronary arteries

Back 30

Deliver blood to the heart

Front 31

What is the effect of cholesterol on blood vessels? What is done if this happens?

Back 31

Forms plaques narrowing the tube and so restricting the blood flow - which if occur in the coronary arteries can cause heart attacks
Stents are used to keep them open

Front 32

Capillaries

Back 32

Carry blood to cells for transporting substances via blood
Has thin walls (only one cell thick) for easier diffusion

Front 33

How does the heart pump blood?

Back 33

Blood enters the atria which then contracts, forcing the blood down into the ventricles
The ventricles then contract forcing the blood out of the heart

Front 34

Double circulation system

Back 34

The heart supplies blood using 2 main pathways - one for the lungs and the other for the rest of the body

Front 35

The pulmonary artery and vein supply what with blood?

Back 35

The lungs

Front 36

The aorta and vena cava supply what with blood?

Back 36

The rest of the body

Front 37

What side are the pulmonary vein and aorta and what do they carry?

Back 37

Left side
They carry oxygenated blood

Front 38

What side are the pulmonary vein and vena cava and what do they carry?

Back 38

Right side
They carry deoxygenated blood

Front 39

What is blood and what is it consisted of?

Back 39

Blood is a tissue which contains white blood cells, red blood cells, plasma and platelets

Front 40

What does blood plasma transport? (3)

Back 40

Carbon dioxide from the organs to the lungs
Soluble materials from the small intestine to the organs
Urea from the liver to the kidneys

Front 41

Haemoglobin

Back 41

A red pigment which is in red blood cells
In the lungs it combines with oxygen to form oxyhaemoglobin; in other organs the oxyhaemoglobin splits back into haemoglobin and oxygen

Front 42

Red blood cells

Back 42

Transport oxygen from the lungs to the organs
They have no nucleus so that there is more space for oxygen

Front 43

White blood cells

Back 43

Part of the body's defence mechanism against microorganisms
They have a nucleus

Front 44

Platelets

Back 44

Fragments of cells which helps the blood to clot at the site of a wound
Has no nucleus

Front 45

Xylem tissue

Back 45

Transports water and mineral ions from the roots to the stem and leaves

Front 46

Transpiration stream

Back 46

The movement of water from the roots through the xylem and out of the leaves

Front 47

Phloem tissue

Back 47

Transports sugar from the leaves to the rest of the plant (for growth and storage)

Front 48

What waste products need to be removed from the body? (2)

Back 48

Carbon dioxide - which is produced in respiration and removed via the lungs
Urea - produced in the liver by the breakdown of excess amino acids and removed by the kidneys as urine which is stored in the bladder until urination

Front 49

If we drink too much or too little water

Back 49

The water and ion content is wrong meaning that too much water may move into or out of the cells by osmosis, damaging the cells

Front 50

How do the kidneys produce urine?

Back 50

It filters the blood and then absorbs all the sugar and only the ions and water that it needs
All of the urea and excess water and ions is released as urine

Front 51

What is a dialysis machine used for and what does it do?

Back 51

People with kidney failure
It has the correct concentrations (the same as blood) of dissolved substances so the blood goes back to normal levels through partially permeable membranes
Blood flows in and waste substances such as urea and water leave, just like a normal kidney would

Front 52

A diseased kidney can be replaced with a healthy one from a

Back 52

Donor

Front 53

What are the advantages and disadvantages of dialysis?

Back 53

There is no risk of rejection and is easier to get than getting a replacement kidney
You have to go through the process very frequently

Front 54

What are the advantages and disadvantages of a kidney transplant?

Back 54

If successful the patient can lead a normal life
The kidney may be rejected by the person's immune system or get infected

Front 55

Why may the body "attack" the donor organ?

Back 55

Our body will not be able to recognise its antigens and so antibodies may "attack" it

Front 56

Antigens

Back 56

Proteins on the surface of cells

Front 57

How can we help prevent a transplanted kidney being rejected? (2)

Back 57

The chosen kidney will have similar "tissue-type" to their one before
The patient is given drugs which suppress the immune system

Front 58

Body temperature is monitored and controlled by the

Back 58

Thermoregulatory centre in the brain which has receptors sensitive to the temperature of the blood flowing through the brain

Front 59

Temperature receptors in the skin send

Back 59

Impulses to the thermoregulatory centre in the brain also providing information about the body's temperature

Front 60

What happens if our core body temperature is too high? (2)

Back 60

The sweat glands release more sweat which cools down the body as it evaporates
The blood vessels dilate supplying the skin capillaries with more blood closer to the surface of the skin so more heat is lost

Front 61

What happens if our core body temperature is too low? (2)

Back 61

Muscles contract rapidly causing them to shiver which needs respiration. More energy is released in order to heat up the body

Front 62

The blood glucose concentration in our body is controlled by the

Back 62

Pancreas

Front 63

What does the pancreas do?

Back 63

Produces the hormones insulin and glucagon

Front 64

What does the hormone insulin do?

Back 64

Allows glucose to move from the blood into our cells

Front 65

What happens if blood glucose levels fall?

Back 65

Glucagon causes glycogen to be converted into glucose which can be released into the blood

Front 66

Liver stores excess glucose as an insoluble molecule called

Back 66

Glycogen

Front 67

The body secretes insulin when

Back 67

The body's blood glucose concentration is too high

Front 68

Type 1 diabetes

Back 68

A disease which means that a person cannot produce enough insulin
As a result, that person is at danger of their blood glucose concentration becoming too high

Front 69

How may type 1 diabetes be controlled? (3)

Back 69

With careful attention to diet, exercise and by injecting insulin

Front 70

Unless waste is properly handled

Back 70

More pollution will be caused

Front 71

Why is more waste being produced?

Back 71

Rapid growth in the human population
Increase of the standard of living

Front 72

Waste may pollute (3)

Back 72

Water - by sewage, fertiliser and toxic chemicals
Air - by gases such as sulphur dioxide which leads to acid rain (destroying habitats)
Land - by pesticides and herbicides which can be washed away into waterways

Front 73

Why is there less land available?

Back 73

We are using it to build, quarry, farm and dump our waste on

Front 74

What are the reasons for deforestation? (3)

Back 74

Timber
To provide land for agriculture - crops from which biofuels, based on ethanol, can be made
We can use some of the products for medicine

Front 75

What are the disadvantages of deforestation?

Back 75

Burning the wood releases carbon dioxide into the atmosphere
Reduces the biodiversity as it destroys habitats
Rice fields and cattle which can be moved onto the new land release methane meaning that more methane is being released into the atmosphere

Front 76

Peat bogs store

Back 76

carbon dioxide which means that by damaging them you release that stored carbon dioxide into the atmosphere

Front 77

Peat bog

Back 77

Marshy ground which contains partially dead material which can be burned or used to make soil better

Front 78

Why is "peat free" compost of increasing importance?

Back 78

Doesn't release carbon dioxide
Does not use up the peat required for dragonflies and birds to survive
Develops quicker than peat compost

Front 79

What contributes to global warming?

Back 79

An increase of carbon dioxide and methane

Front 80

What are the effects of global warming? (5)

Back 80

Changes climates
Sea levels rise
Reduces biodiversity
Changes migration patterns
Changes the distribution of species

Front 81

How can oceans and lakes remove carbon dioxide from the atmosphere?

Back 81

Sequestration

Front 82

Biofuels

Back 82

Natural products containing carbohydrates anaerobically ferment creating biogas which is mainly methane

Front 83

As you go up the stages in the food chain

Back 83

The biomass of the organisms decrease

Front 84

How can we make food production more efficient? (3)

Back 84

Reducing the number of stages in food chains
Restricting energy loss from food by movement
Restricting energy less from heat by controlling the temperature of their surroundings

Front 85

Why are fish stocks declining? (2)

Back 85

Fish are being taken at a faster rate than they breed
Fisherman have to keep up their living despite the threat of extinction

Front 86

What helps conserve the fish stocks?

Back 86

Quotas
Net size

Front 87

What fungus produces mycoprotein?

Back 87

Fusarium

Front 88

Mycoprotein - what is it and how is it produced?

Back 88

A protein-rich food suitable for vegetarians which is grown in glucose syrup in aerobic conditions which is then harvested and purified