A Level Biology Chapter 13 Photosynthesis

Proton pumps establish electrochemical gradients, which are required for ATP production.

Which regions of a plant cell are protons pumped into?

• Thylakoid space and mitochondrial matrix

• Thylakoid space and mitochondrial intermembrane space

• Chloroplast stroma and mitochondrial matrix

• Chloroplast stroma and mitochondrial intermembrane space

Which graph shows how temperature affects the rate of anaerobic respiration in yeast?

• A

• B

• C

• D

What is a similarity in the way ATP is made in respiration and photosynthesis?

• Both involve photons

• Both involve proton gradients

• Both involve substrate level phosphorylation

• Both involve NAD

Which statement describes and explains the relative yield of ATP in anaerobic and aerobic respiration?

• Anaerobic respiration produces less ATP per molecule of glucose because lactate is converted to pyruvate

• Anaerobic respiration produces less ATP per molecule because NAD is not regenerated in oxidative phosphorylation

• Anaerobic respiration produces more ATP per molecule because NAD is regenerated in oxidative phosphorylation

• Anaerobic respiration produces more ATP per molecule because pyruvate is converted to lactate

Phospholipid bilayers play crucial roles within plant cells.

Which statement(s) linked to the importance of membranes in plant cells is/are true?

1 - ATP synthase embedded in thylakoid membranes maintains chemiosmotic gradients

2 - phospholipid bilayers within the chloroplast are impermeable to protons

3 - thylakoid membranes contain electron transport chain proteins

• only 1

• only 1 and 2

• only 2 and 3

• 1, 2 and 3

RuBisCO is an enzyme that fixes carbon dioxide in photosynthesis. In some conditions, RuBisCO also carries out oxygen fixation.

The graph below shows how the carbon dioxide and oxygen fixing activities of RuBisCO are affected by temperature.

What are the correct percentage changes in RuBisCO carbon dioxide and oxygen fixing activities between 30°C and 40°C?

• carbon dioxide fixation -3.6%, oxygen fixation 35.1%

• carbon dioxide fixation -2.4%, oxygen fixation 54.2%

• carbon dioxide fixation -14.6%, oxygen fixation 18.9%

• carbon dioxide fixation -12.7%, oxygen fixation 23.3%

What is the source of electrons in photosynthesis?

Photolysis is the process of splitting water using light energy.

What is the region of the chloroplast in which this process takes place?

The statements below relate to the Calvin cycle:

1 - molecules of triose phosphate are required for the synthesis of nucleic acids

2 - the production of triose phosphate from glycerate-3-phosphate requires ATP and reduced NAD

3 - reactions of the Calvin cycle occur at a faster rate when stomata are closed

Which statement(s) is/are correct?

• 1, 2, and 3 are correct

• only 1 and 2 are correct

•   

  only 2 and 3 are correct

• only 1 is correct

How many molecules of CO₂ must enter the Calvin cycle to produce one molecule of glucose?