Bioenergetics

Question 1

Give 5 ways glucose can be used in plants.

Forgot 2

Answer 1

Lipids in seeds
Starch for storage
Combining with nitrate ions to make amino acids
Respiration
To make cellulose for cell walls

Question 2

Give 3 reasons why it is beneficial to keep plants enclosed in a greenhouse.

Answer 2

Can regulate the temperature/CO₂ concentration/light hours
Reduces the number of pathogens/pests that can reach the plants
Can add fertilisers to the soil to provide all the minerals needed for healthy growth

Question 3

Where does lactic acid go to to be converted into something safe? What is this other substance?

Answer 3

Liver, to be converted into glucose.

Question 4

Explain what muscle fatigue is and when this occurs.

Answer 4

During long periods of exercise, the muscles get tired and so stop contracting efficiently.

Question 5

Explain what an oxygen debt is and when you would get it.

Answer 5

Oxygen debt is the amount of extra oxygen your body needs after exercise to react with the build up of lactic acid produced due to anaerobic respiration in the muscles and remove it from the cells.

Question 6

Give 3 examples of metabolic reactions.

Answer 6

• Respiration
• Combining glucose with nitrate ions to make amino acids, which can then be formed into proteins
• Breaking down excess protein into urea
• The polymerisation of glucose into starch, glycogen or cellulose
• Forming lipid molecules from one molecule of glycerol and three fatty acids