Respiration

Question 1

Word equation for aerobic respiration

Answer 1

Glucose + oxygen –> carbon dioxide + water (+ energy)

Question 2

Symbol equation of chemical reaction for aerobic respiration

Answer 2

C6H12O6 + 6O2 → 6CO2 + 6H2O

Question 3

Where do most of the reactions in aerobic respiration take place

Answer 3

Inside mitochondria

Question 4

What may the energy that is released during respiration be used by organisms for

Answer 4

to build larger molecules from smaller ones

Question 5

What may the energy that is released during respiration be used by animals for

Answer 5

to enable muscles to contract

Question 6

What may the energy that is released during respiration be used by mammals and birds for

Answer 6

to maintain a steady body temperature in colder surroundings

Question 7

What may the energy that is released during respiration be used by plants for

Answer 7

to build up sugars, nitrates and other nutrients into amino acids, which are then built up into proteins

Question 8

What changes take place during exercise when the human body needs to react to the increased demand for energy

Answer 8

• the heart rate increases, increasing blood flow to the muscles,
• the rate and depth of breathing increases,
• glycogen stored in the muscles is converted back into glucose

Question 9

What do the changes that take place during exercise when the human body needs to react to the increased demand for energy do

Answer 9

these changes increase the supply of glucose and oxygen to the muscles, and increase the rate of removal of carbon dioxide from the muscles

Question 10

When is energy produced by anaerobic respiration

Answer 10

if insufficient oxygen is reaching the muscles

Question 11

chemical reaction of anaerobic respiration word equation

Answer 11

glucose –> lactic acid (+energy)

Question 12

chemical reaction of anaerobic respiration symbol equation

Answer 12

C6H12O6 = 2C2H5OH (+energy)

Question 13

what is anaerobic respiration in muscles

Answer 13

anaerobic respiration in muscles is the incomplete breakdown of glucose, which causes a build-up of lactic acid

Question 14

why does oxygen debt need to be repaid

Answer 14

an oxygen debt needs to be repaid to oxidise the lactic acid to carbon dioxide and water

Question 15

why is much less energy released in anaerobic respiration than during aerobic respiration

Answer 15

because the breakdown of glucose is incomplete in anaerobic respiration

Question 16

what happens during long periods of vigorous activity

Answer 16

muscles become fatigued and stop contracting efficiently

Question 17

what is a cause of muscle fatigue

Answer 17

the build up of lactic acid in the muscles

Question 18

what eventually removes the lactic acid in the muscles

Answer 18

blood flowing through the muscles

Question 19

what does anaerobic respiration in plant cells and in some micro organisms result in

Answer 19

the production of ethanol and carbon dioxide