2 i+h

Question 1

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

Answer 1

• Oxygen (O2) is produced as a waste product of photosynthesis
• Carbon diovide (CO2) is produced as a waste product of respiration

Question 2

3 Waste products produced in the body

Answer 2

• Urea
• Carbon dioxide
• Excess salt and water

Question 3

3 excretory organs

Answer 3

• The lungs
• The kidneys
• The skin

Question 4

2 reasons why unicellular organisms can rely on diffusion alone

Answer 4

• They have a large surface area to volume ratio due to their size
• They have low metabolic demands

Question 5

What does the phloem transport

Answer 5

Sugars like sucrose and amino acids

Question 6

What direction does the phloem transport sugars

Answer 6

The phloem tranpsort sugars up from leaves to each part of the plant

Question 7

What does the xylem transport

Answer 7

water and minerals

Question 8

What direction does the xylem transport water and minerals?

Answer 8

Up the plants (from the roots to the leaves)

Question 9

How are root hair cells adapted to their function

Answer 9

• Long root hair extension to increase surface area for uptake
• Thin membranes to decrease the diffusion distance

Question 10

3 benefits of traspiration

Answer 10

• the stream of water cools the plant
• the water helps to support the plant by creating turgor pressure
• the plant has a constant water supply for photosynthesis

Question 11

How is the xylem adapted to transport water?

Answer 11

• It is waterproofed using a substance called lignin
• The xylem cells are dead and have no organelles so there is more space for water

Question 12

4 components of the blood

Answer 12

• Red blood cells
• White blood cells
• Platelets
• Plasma

Question 13

What is the function of platelets

Answer 13

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

Question 14

How are red blood cells adapted to their function?

Answer 14

• Contain haemoglobin to carry oxygen
• Biconcave shape to maximise surface area and allow them to squeze through capillaries
• No nucleus to maximise space for haemoglobin

Question 15

What is the purpose of plasma?

Answer 15

Plasma is the liquid part of the blood
- its purpose is to act as a transport medium
- to transport CO2, hormones, nutrients and waste products.

Question 16

What is the function of white blood cells?

Answer 16

White blood cells are involved in phagocytosis and some white blood cells produce antibodies.

Question 17

What is a pathogen

Answer 17

A disease-causing microorganism

Question 18

2 ways that the body can responf to detecting a pathogen

Answer 18

• Lymphocytes can produce antibodies that are specific to the antigens on the pathogen
• Phagocytes can engulf the pathogen

Question 19

Describe the double circulatory system in mammals

Answer 19

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

Question 20

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

Answer 20

• Arteries carry blood Away from the heart
• veINs carry blood towards (INto) the heart
• Capillaries flow close to tissues for exchange

Question 21

Describe the structure of arteries

Answer 21

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

Question 22

Descibe the structre of capillaries

Answer 22

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

Question 23

Describe the structure of veins

Answer 23

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

Question 24

Describe the blood flow through the right side of the heart

Answer 24

• Deoxygenated blood flows into the right atrium from vena cava
• This blood passes through the right AV valve into the right ventricle
• The blood is the pumped out of the heart to the lungs through the right SL valve or pulmonary valve and into the pulmonary artery

Question 25

Describe the blood flow through the left side of the heart

Answer 25

• Blood enters into the left atrium from the pulmonary vein
• The bloof 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

Question 26

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

Answer 26

The septum

Question 27

Name of artery that supplies the heart tissue with blood

Answer 27

coronary artery

Question 28

What type of muscle is the heart made of

Answer 28

Cardiac muscle

Question 29

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

Answer 29

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

Question 30

What does adrenaline do the the heart rate

Answer 30

Adrenaline increases the heart rate as it triggers the “fight or flight” reflex

Question 31

2 parts of the body (aside heart) that adrenaline affects

Answer 31

• Adrenaline dilates the pupils
• Adrenaline increases the breathing rate

Question 32

Why does the heart rate increase during exercise?

Answer 32

• 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

Question 33

What is the coronary heart disease (CHD)

Answer 33

When the artery providing the heart tissue with blood becomes blocked

Question 34

3 common risk factors for CHD

Answer 34

• Smoking
• Poor diet
• Lack of exercise