Respiration and Gas Exchange

Question 1

What is respiration?

Answer 1

Release of energy for cells from glucose. The energy is captured in a molecule called ATP

Question 2

What is Aerobic respiration?

Answer 2

breakdown of glucose to release energy in the presence of oxygen

Question 3

What is Anaerobic respiration?

Answer 3

breakdown of glucose to release energy in the absence of oxygen

Question 4

What is the word equation for aerobic respiration?

Answer 4

Glucose+Oxygen → Carbon dioxide+Water

Question 5

What is the chemical equation for aerobic respiration?

Answer 5

C6H12O6 + 6O2 → 6CO2 + 6H2O

Question 6

What is the word equation for anaerobic respiration (animals)?

Answer 6

Glucose→Lactic acid

Question 7

What is the word equation for anaerobic respiration in yeast and plants?

Answer 7

Glucose→ Ethanol+Carbon dioxide

Question 8

Does aerobic or anaerobic respiration produce more energy?

Answer 8

Aerobic

Question 9

Is glucose breakdown complete or incomplete in aerobic respiration?

Answer 9

complete

Question 10

Method for using respiring organisms to investigate the production of carbon dioxide

Answer 10

-Capillary tube is connected from the air (inlet pipe) into a flask of sodium hydroxide
-This flask is connected by a capillary tube to a flask of hydrogen carbonate indiactor A
-This flask is connected by a capillary tube to a flask of respiring organisms
-This flask is connected by a capillary tube to a flask of hydrogen carbonate indicator B
-Finally, this flask is connected by a capillary tube to the air as an exit pipe

Question 11

What are the results of the experiment?

Answer 11

-As air enters the first capillary tube, carbon dioxide in the air will be absorbed by the sodium hydroxide, causing the hydrogen carbonate indicator A to turn red (atmospheric level)
-The flask of respiring organisms will respire aerobically, producing carbon dioxide as a waste product, causing the hydrogen carbondate indicator to turn yellow (high levels of carbon dioxide)
-This shows the evolution of carbon dioxide in living organisms

Question 12

What are ribs?

Answer 12

a boney cage that protects internal organs such as the lungs

Question 13

What are intercostal muscles?

Answer 13

Muscles between the ribs to control it during ventilation

Question 14

What colour will hydrogen carbonate turn when its:
a)atmospheric levels
b)high carbon dioxide
c)low carbon dioxide

Answer 14

a)red
b)yellow
c)purple

Question 15

What is the diaphragm?

Answer 15

Sheet of muscle at the bottom of the thorax

Question 16

What is the trachea?

Answer 16

Air pipe that connects the mouth and nose to the lungs

Question 17

What are bronchi?

Answer 17

The trachea divides into two bronchi, with one bronchus for each lung

Question 18

What are bronchioles?

Answer 18

Bronchi will split to form smaller tubes called bronchioles. These connect to alveoli.

Question 19

What are alveoli?

Answer 19

Tiny air sacs where gas exchange takes place.

Question 20

What are pleural membranes?

Answer 20

Separates the inside of the thorax from the lungs. Creates a continuous layer that forms an airtight seal. Made of two thin layers filled with pleural fluid, which lubricates the lugs s they don’t stick to the inside of the chest wall as we breathe.

Question 21

What happens to organs during inhalation?

Answer 21

-Intercostal muscle will contract, pulling downwards
-Diaphragm will contract, pulling downwards
-Volume increases, pressure decreases
-Air is drawn in

Question 22

What happens during exhalation?

Answer 22

-Intercostal muscles will relax, pushing ribcage down and in
-Diaphragm will relax, pushing upwards
-Volume decreases, pressure increases
-Air is pushed out

Question 23

Why are alveoli folded?

Answer 23

Increases the surface area to volume ratio for the diffusion of gases

Question 24

Why do alveoli have thin cell walls?

Answer 24

Once cell thick so the distance of diffusion is short, increasing the rate of diffusion of gases

Question 25

Why do alveoli have good blood supply?

Answer 25

Each alveolus is surrounded by blood capillaries with blood that is constantly flowing to maintain a large concentration gradient between the air inhaled in and the blood in the capillaries.

Question 26

Why is each alveolus ventilated?

Answer 26

Moving ai in and out of the alveoli regularly replenishes the supply of oxygen and removes the air with higher carbon dioxide concentration. This helps to maintain a large concentration gradient between the air and the blood.

Question 27

What are 5 chemicals in cigarettes?

Answer 27

Tar, Nicotine, Carcinogens, Carbon Monoxide, Poisons

Question 28

What is the effect of tar (from cigarettes) on the body?

Answer 28

Blocks up alveoli, making gas exchange more difficult. Reduces the surface area available. Also clogs up cilia, which wave and remove mucus and trapped bacteria out of the lungs.

Question 29

What is the effect of nicotine (cigarettes) on the body?

Answer 29

Speeds heart rate and damages arteries, causing furring of the artery (artherosclerosis). This leads to heart disease and vascular diseases. It is also addictive

Question 30

What is the effect of carcinogens (cigarettes)?

Answer 30

Damages the DNA of alveoli cells. This can lead to them reproducing faster than normal, which will cause a tumour to form. The tumour is the start of cancer.

Question 31

What is the effect of Carbon Monoxide (cigarettes)?

Answer 31

Attaches permanently to haemoglobin, reducing the ability of blood to carry 02.

Question 32

What are some examples of poisons in cigarettes?

Answer 32

There are over 5000 poisonous chemicals in cigarette smoke: e.g. benzene, arsenic, lead, cyanide

Question 33

Describe an experiment of exercise on breathing in humans.

Answer 33

Take your own heart rate, breathing rate and skin temperature at rest. Do some exercise, then take the same measurements again. They will have all increased. This is because your rate of respiration has increased (to supply the muscles with extra energy for contraction). For respiration to happen faster, you also need more 02,so breathing and heart rate increase. You also release more waste heat energy, so your body heats up and you have to sweat to cool down again.