Bioenergetics

Question 1

Equation for photosynthesis

Answer 1

Carbon dioxide + Water ———-> Glucose + Oxygen

Question 2

Equation for respiration

Answer 2

Glucose + Oxygen ———–> Carbon Dioxide + Water

Question 3

After 10 minutes the limewater in flask B was cloudy, but the limewater in flask A remained colourless. Explain why

Answer 3

atmospheric air contains less carbon dioxide than exhaled air
carbon dioxide is produced in (aerobic) respiration (by
woodlice)

Question 4

Exercise cannot be sustained when anaerobic respiration takes place in muscle cells. Explain why.

Answer 4

muscles become fatigued / stop contracting
because not enough energy is transferred

Question 5

Explain how oxygen passes through the blood

Answer 5

diffusion, high to low concentration, through (cell) membrane/cytoplasm

Question 6

The pancreas cell makes enzymes. Enzymes are proteins. Describe how the ribosomes and mitochondria help the cell to make enzymes.

Answer 6

ribosomes make proteins / enzymes
using amino acids
mitochondria provide the energy for the process

Question 7

During exercise, more oxygen is carried to the working muscles.
Explain why this is helpful during exercise.

Answer 7

for respiration
prevents anaerobic respiration
prevents build-up of lactic acid