Transpiration

Question 1

What is the function of the upper epidermis?

Answer 1

It’s a waxy waterproof layer that reduces water loss

Question 2

What is the function of each mesophyll layer?

Answer 2

Palisade mesophyll - absorbs light for photosynthesising contains many chloroplasts

Spongy mesophyll - has air spaces which allow gases to reach leaf cells for photosynthesis

Question 3

What is the function of the lower epidermis?

Answer 3

Contains pores called stomata which allows gases to diffuse in and out of the leaf

Question 4

What is the function of the stomata?

Answer 4

Allows water vapour to leave and is the site of gas exchange

Question 5

What is the function of the guard cells?

Answer 5

Controls the opening and the closing of the stomata

Question 6

What to water and minerals enter the plant through?

Answer 6

Specialised cells called root hair cells

Question 7

What process does water move by?

Answer 7

Osmosis

Question 8

Explain how water and minerals are transported in plants

Answer 8

The water moves via osmosis from the soil into the root hair cells. The water and minerals are then transported from the roots to other parts of the plant.

Question 9

What vessels are water and minerals transported?

Answer 9

Xylem vessels

Question 10

Do xylem cells have cell contents?

Answer 10

No

Question 11

What tough, waterproof substance is xylem vessels lined with?

Answer 11

Lignin

Question 12

What does lignin enable the xylem cells to do?

Answer 12

Withstand the pressure changes as water moves through the plant

Question 13

How is lignin arranged and what does it provide to the cells?

Answer 13

Lignin is arranged as rings/spirals and provided support to the cells

Question 14

When xylem cells are laid end to end, what do they form?

Answer 14

A rigid pipe

Question 15

What is produced in the leaves during photosynthesis?

Answer 15

Sugar

Question 16

The sugar is then transported up and down the plant in what?

Answer 16

Living phloem cells

Question 17

What 2 thing do phloem cells have?

Answer 17

Sleve plates and associated companion cells

Question 18

What do companion cells provide for sleve cells?

Answer 18

Energy

Question 19

What do sleve played have and what can be transported?

Answer 19

They have pores which sugar can be transported

Question 20

Define transpiration

Answer 20

The process of water moving through a plant and its evaporation through the stomata

Question 21

Explain the 3 stages of transpiration

Answer 21

1. Water enters into plant through root hair cells by the process of osmosis.
2. Xylem vessels transport water into the leaves.
3. Water evaporates from the leaf through stomata.

Question 22

What internal factor affects the rate of transpiration?

Answer 22

The surface area

Question 23

Smaller leaves contain less what causing a decrease in the rate of transpiration?

Answer 23

Less stomata

Question 24

List 3 external factors that can also affect the rate of transpiration

Answer 24

1. Increase in temperature
2. Increase in wind speed
3. decrease in humidity

Question 25

What term is used to describe guard cells when the plant has plenty of water and why is this?

Answer 25

Turgid so that water can leave the plant

Question 26

What term is used to describe guard cells when plants lack water and why?

Answer 26

Plasmolyses to prevent further water loss

Question 27

What is blood?

Answer 27

The liquid that circulated throughout the body

Question 28

What does blood transport?

Answer 28

Carbon dioxide, oxygen and nutrients

Question 29

If blood is bright red in colour, what is it described as?

Answer 29

Oxygenated

Question 30

If blood is dark red in colour, what is it described as?

Answer 30

Deoxygenated

Question 31

In mammals, what are the 3 contents of blood?

Answer 31

Plasma, red blood cells and white blood cells

Question 32

Name and deceive 3 features of a red blood cell that enables it to efficiently carry out its function

Answer 32

1. Biconcave shape - maximises the surface area of the cell membrane for oxygen to diffuse across. 2. No nucleus - creates more space inside the cell to carry more oxygen. 3. Contain haemoglobin - a protein that binds to oxygen and efficiently transport it in the form of oxyhaemoglobin.

Question 33

Where does haemoglobin bind with oxygen when oxygen concentration is high?

Answer 33

The lungs and forms oxyhaemoglobin

Question 34

Where in the body does haemoglobin release oxygen if oxygen concentration is low?

Answer 34

Body tissues and therefore the oxygen diffuses into the cells.

Question 35

What system are white blood cells part of?

Answer 35

Immune system

Question 36

What are white blood cells involved in?

Answer 36

Destroying pathogens

Question 37

What are pathogens? Give the 3 types

Answer 37

Disease causing micro organisms 1. Bacteria 2. Fungi 3. Viruses

Question 38

What are the 2 main types of white blood cells involved?

Answer 38

Phagocytes and lymphocytes

Question 39

What is the function of phagocytes?

Answer 39

To destroy pathogen via the process of phagocytosis

Question 40

Explain the 3 stages of phagocytes destroying pathogens

Answer 40

1. Phagocyte encounters pathogen. 2. Phagocyte engulfs pathogen. 3. Phagocyte releases enzymes to digest and destroy pathogen.

Question 41

What is the function of lymphocytes?

Answer 41

To produce antibodies which destroy pathogens

Question 42

What term is used to describe the relationship between the antibody and pathogen?

Answer 42

Each antibody is specific to a particular pathogen.

Question 43

Blood travels through the circulatory system through tubes called what?

Answer 43

Blood vessels

Question 44

What are the 3 main types of blood vessels in the circulatory system?

Answer 44

Arteries, veins and capillaries

Question 45

What is the function of the arteries?

Answer 45

To carry blood away from the heart

Question 46

Give 3 factors of arteries.

Answer 46

1. They have thick muscular walls 2. A narrow central channel 3. Blood is carried under high pressure

Question 47

What is the function of the veins?

Answer 47

To carry blood towards the heart

Question 48

Give 3 factors of veins

Answer 48

1. They have thin walls and a wide central channel. 2. They carry blood under low pressure. 3. They contain valves to prevent the back flow of blood

Question 49

What is the function of the capillaries?

Answer 49

They are exchange vessels found between arteries and veins

Question 50

What allows capillaries to easily allow materials to diffuse across them?

Answer 50

They’re walls are only one cell thick

Question 51

The large number of capillaries gives them a large surface area to form what?

Answer 51

Networks at tissues and organs

Question 52

What diffuses from the capillaries into the cells?

Answer 52

Oxygen and glucose

Question 53

What diffuses from the cells into the capillaries?

Answer 53

Carbon dioxide and urea

Question 54

The heart is a minor organ of what system?

Answer 54

Circulatory system

Question 55

What is the function of the heart?

Answer 55

To pump blood around the body

Question 56

Where is the heart found and what is it protected by?

Answer 56

Found in the chest and is protected by the rib cage

Question 57

What is the heart made of?

Answer 57

Cardiac muscle

Question 58

What type of blood does the left side of the heart pump and where does it pump it to?

Answer 58

Oxygenated blood to the body cells

Question 59

What type of blood does the right side of the heart pump and where does it pump it to?

Answer 59

Deoxygenated blood to the lungs

Question 60

Name the 8 chambers and blood vessels found in the heart

Answer 60

1. Right atrium 2. Right ventricle 3. Vena cava 4. Pulmonary artery 5. Aorta 6. Pulmonary vein 7. Left atrium 8. Left ventricle

Question 61

What is the function of the valves?

Answer 61

To prevent the back flow of blood

Question 62

State the 2 types of valves and where they are found

Answer 62

Semi lunar valves- found at the exit to the pulmonary artery and aorta. AV valves - found between the atria and the ventricles.

Question 63

Explain the pathway of blood

Answer 63

1. Deoxygenated blood enters the right atrium via the main vein, the vena cava. 2. The right atrium contracts, pumping deoxygenated blood into the right ventricle. 3. Contraction of the ventricle moves deoxygenated blood into the pulmonary artery. The pulmonary artery carries deoxygenated blood to the lungs where it takes up oxygen. 4. The pulmonary vein returns oxygenated blood from the lungs to the left atrium of the heart. 5. the oxygenated blood is then pumped into the left ventricle. 6. Contraction of the left ventricle forces oxygenated blood into the main artery, the aorta. The aorta takes oxygenated blood to all parts of the body for tissues and organs to use.