Topic 8 🫀

Question 1

Formula for aerobic respiration

Answer 1

Glucose + oxygen ———-> energy + carbon dioxide + water

Question 2

Which substances are exchanged by diffusion in the alveoli

Answer 2

Oxygen and carbon dioxide

Question 3

What 3 factors affect the rate of exchange of substances in the lungs

Answer 3

Surface area
Diffusion distance
Concentration gradient

Question 4

What adaptations does a capillary have to ensure quick diffusion

Answer 4

Walls only one cell thick so particles don’t have far to diffuse
Large surface area so there is room for particles to diffuse

Question 5

Name the 4 substances in the blood

Answer 5

Red blood cells
White blood cells
Platelets
Plasma

Question 6

What are the two types of white blood cell

Answer 6

Lymphocytes and phagocytes

Question 7

What does plasma do

Answer 7

Liquid which carries dissolved substances (glucose co2 and urea) around the body

Question 8

What is the function of a red blood cell

Answer 8

Carry oxygen

Question 9

What is the function of the white blood cell

Answer 9

Fight disease

Question 10

What is the function of platelets

Answer 10

Helps the blood to clot

Question 11

What are the three main types of blood vessels in the circulatory system

Answer 11

Arteries
Veins
Capillaries

Question 12

What do arteries do?

Answer 12

Carry blood AWAY from the heart

Question 13

What do veins do

Answer 13

Carry blood BACK to the heart

Question 14

What do capillaries do?

Answer 14

Carries blood through organs and tissues

Question 15

What ADAPTATIONS do the ARTERIES have TO COPE WITH HIGH PRESSURE

Answer 15

Thick elastic muscular walls stretch as blood arrives from heart
The relaxation of the muscle helps to reduce variation in blood pressure and make blood flow smoothly

Question 16

What adaptations do the veins have

Answer 16

Width allows blood to flow more easily back to the heart
Valves stop the back flow of blood when muscles contract

Question 17

Why is the circulatory system called the ‘double circulatory system

Answer 17

Heart has 2 pumps

Question 18

What does the left side of the heart do

Answer 18

Pumps the oxygenated blood brought back from the lungs around the body

Question 19

What does the right hand side of the heart do

Answer 19

Pumps the deoxygenated blood to the lungs to collect oxygen

Question 20

Which side of the heart has a thicker muscular wall and why

Answer 20

Left because it has to pump the blood all around the body

Question 21

What do the tendons do

Answer 21

Stop the valves turning inside out

Question 22

What causes each heartbeat

Answer 22

Contraction and relaxation of cardiac muscle controlled by impulses from the nervous system

Question 23

What is heart rate

Answer 23

The number of times the heart beats per minute (bpm)

Question 24

What is stroke volume

Answer 24

The volume of blood pushed into the aorta in each beat (litres)

Question 25

What is cardiac output

Answer 25

The volume of blood pushed through the aorta in each minute

Question 26

Cardiac output =

Answer 26

Stroke volume x heart rate

Question 27

What is the correlation between fitness levels and cardiac output

Answer 27

Regular EXERCISE INCREASES the STRENGTH of the HEART muscle and VENTRICLE SIZE FITTER PEOPLE often have a BIGGER STROKE VOLUMES and their HEARTS can BEAT SLOWER to achieve the SAME CARDIAC OUTPUT as a less fit person

Question 28

Rate of diffusion =

Answer 28

Surface area x concentration difference ——————————————————- thickness of membrane

Question 29

Explain how the heart causes blood to flow to the lungs

Answer 29

Right atrium —- right ventricle —- muscle contracts —- blood moves into pulmonary artery

Question 30

Are concentration gradient and rate of diffusion directly or inversely proportional?

Answer 30

Directly proportional

Question 31

Are surface area and rate of diffusion directly or inversely proportional?

Answer 31

Directly proportional

Question 32

Are thickness of membrane and rate of diffusion directly or inversely proportional?

Answer 32

Inversely

Question 33

How are the alveoli adapted for gas exchange

Answer 33

Large surface area (more diffusion of oxygen into blood and co2 out of blood) One cell thick (diffusion distance is small) Good blood supply to maintain concentration gradient

Question 34

Word equation for anaerobic respiration

Answer 34

Glucose —-> lactic acid

Question 35

Why does the amount of lactic acid in the body decrease after exercise

Answer 35

Lactic acid is poisonous so must be removed by liver

Question 36

Compare aerobic and anaerobic respiration

Answer 36

Aerobic : requires oxygen releases more energy from glucose Takes place during low intensity exercise

Question 37

Where does aerobic respiration occur

Answer 37

Mitochondria

Question 38

Where does anaerobic respiration occur

Answer 38

Cytoplasm

Question 39

What is a possible problem that could occur when undergoing a kidney transplant and how is it solved?

Answer 39

Antigens on transplanted kidney are difference to the antigens in the cells of the patients body therefore … Antigens on transplanted kidney and patients tissue must be as similar type as possible AND patient must take life drugs to reduce the effects of the immune system as patients could get more infections than usual

Question 40

What does the AORTA carry?

Answer 40

Carries oxygenated blood from the heart to the body

Question 41

What does the VENA CAVA carry?

Answer 41

Carries deoxygenated blood to the heart

Question 42

What does a build up of lactic acid cause

Answer 42

Cramp or fatigue

Question 43

How is lactic acid removed

Answer 43

It is taken to the LIVER and either… oxidised to form carbon dioxide and water OR converted to glucose, then glycogen - glycogen levels in the liver and muscles can then be restored

Question 44

What is oxygen debt?

Answer 44

The amount of oxygen required to remove the lactic acid, and replace the body's reserves of oxygen after intense excercise

Question 45

Describe movement of gases in the alveoli

Answer 45

Blood low in oxygen & high in CO2 enters CO2 diffuses from blood to be exhaled Oxygen diffuses into the blood Blood low in CO2 & high in oxygen leaves

Question 46

Why does breathing depth and rate increase during exercise

Answer 46

Cells need more oxygen and glucose for energy Cells produce more co2 as a result and it needs to be removed