gas exchange and respiration

Question 1

alveoli features

Answer 1

• large surface area
• one cell thick
• blood supply from capillaries
• air constantly entering and leaving

Question 2

limewater in presence of CO2

Answer 2

clear to cloudy

Question 3

function of cartilage in trachea

Answer 3

support the trachea + prevent from collapsing

Question 4

inhalation

Answer 4

• e.i.m contracts i.i.m relaxes
• ribs move up + outward
• diaphragm contracts + flattens
• volume of thorax + lungs increases
• pressure decreases
• air enters + inflates alveoli

Question 5

exhalation

Answer 5

• i.i.m contracts e.i.m relaxes
• ribs move down+ inward
• diaphragm relaxes + returns to dome shape
• volume of thorax + lungs decreases
• pressure increases
• air is forced out of the lungs

Question 6

oxygen in inspired air

Answer 6

21%

Question 7

oxygen in expired air

Answer 7

16%

Question 8

CO2 in inspired air

Answer 8

0.04%

Question 9

CO2 in expired air

Answer 9

4%

Question 10

water vapour in inspired air

Answer 10

less

Question 11

water vapour in expired air

Answer 11

saturated/more

Question 12

how brain monitors and controls rate of breathing when you exercise

Answer 12

• special part to control it
• respire more so more CO2 + maybe lactic acid
• lowered pH is detected
• signals sent to i.m + diaphragm to contracts faster
• increased rate + depth of breathing removes CO2
• pH returns to normal

Question 13

goblet cell

Answer 13

produce mucus to trap dust + bacteria + pathogens

Question 14

ciliated cell

Answer 14

have cilia that sweep mucus towards throat to swallow

Question 15

respiration

Answer 15

chemical reactions in cells that breakdown nutrient molecules to release energy

Question 16

uses of energy

Answer 16

• synthesis of substances
• cell division + growth
• maintenance of a constant body temperature
• active transport in cells
• electrical transmission of nerve impulses
• muscle contraction

Question 17

aerobic respiration

Answer 17

chemical reactions in cells that use oxygen to break down food molecules to release energy

Question 18

word + chemical equation of aerobic respiration

Answer 18

glucose + oxygen → carbon dioxide + water
C6H12O6 + 6O2 → 6CO2 + 6H2O

Question 19

anaerobic respiration

Answer 19

chemical reaction in cells that break down nutrient molecules to release energy without using oxygen

Question 20

word + chemical equation of anaerobic respiration in yeast

Answer 20

glucose → ethanol + carbon dioxide
C6H12O6 → 2C2H5OH + 2CO2

Question 21

word equation of anaerobic respiration in muscle cells

Answer 21

glucose → lactic acid

Question 22

how oxygen debt develops and is repaid

Answer 22

• anaero. produces lactic acid during vigorous exercise
• formation of oxygen debt
• to repay debt breathing increases to supply oxygen for aerobic respiration
• heart beats faster to increase circulation so lactic acid can be carried to liver quickly
• aerobically converted to glucose