GCSE BIOLOGY – BIOENERGETICS EXAM REVISION QUESTIONS
WITH VERIFIED SOLUTIONS LATEST 2025 UPDATE.
What does photosynthesis convert carbon dioxide and water into? - answer- oxygen and
glucose
Where does photosynthesis occur? - answer- in the chloroplast
What type of reaction is photosynthesis? - answer- endothermic
High chlorophyll concentration gives.... - answer- a high rate of photosynthesis
A greater light intensity means...
Why? - answer- a greater rate of photosynthesis.
This is because more energy is being provided.
What happens if the light intensity is increased above a certain threshold? - answer- the rate of
photosynthesis will not increase because another factor (such as temperature) is limiting the rate
of the reaction.
Increasing the carbon dioxide concentration increases...
Why? - answer- the rate of photosynthesis because carbon dioxide is a reactant in
photosynthesis.
What happens if the carbon dioxide concentration is increased above a certain threshold? - answer-
further increases in the carbon dioxide concentration do not increase the rate of photosynthesis
because another factor (such as light intensity) is limiting the rate of reaction.
Increasing the temperature increases...
, Why? - answer- the rate of photosynthesis because more energy is provided.
What happens if the temperature is increased above 45°c,? - answer- the enzymes that catalyse
(speed-up) the reaction begin to denature (not work anymore).
This causes the rate of the reaction to drop sharply until it stops altogether.
What is the limiting factor for photosynthesis in winter? - answer- temperature
What is the limiting factor for photosynthesis in mineral-deficient soil? Why? - answer- if
plants are grown in mineral-deficient soil, they may not absorb enough minerals to produce lots of
chlorophyll.
In this case, chlorophyll concentration can be the limiting factor.
What is the limiting factor for photosynthesis at night? - answer- light intensity
What is the limiting factor for photosynthesis in warm and bright conditions? - answer- carbon
dioxide concentration
Co2 concentration, light levels and temperature are all at optimum values.
What might be the limiting factor of rate of photosynthesis, and why? - answer- the
concentration of mineral ions in the soil is probably the limiting factor.
Chlorophyll absorbs light energy and the production of chlorophyll requires these mineral ions
(especially mg2+).
What happens if a farmer increases the lighting and heating in a greenhouse? - answer- increase
in rate of photosynthesis
Farming may become too expensive
Crops grow faster
WITH VERIFIED SOLUTIONS LATEST 2025 UPDATE.
What does photosynthesis convert carbon dioxide and water into? - answer- oxygen and
glucose
Where does photosynthesis occur? - answer- in the chloroplast
What type of reaction is photosynthesis? - answer- endothermic
High chlorophyll concentration gives.... - answer- a high rate of photosynthesis
A greater light intensity means...
Why? - answer- a greater rate of photosynthesis.
This is because more energy is being provided.
What happens if the light intensity is increased above a certain threshold? - answer- the rate of
photosynthesis will not increase because another factor (such as temperature) is limiting the rate
of the reaction.
Increasing the carbon dioxide concentration increases...
Why? - answer- the rate of photosynthesis because carbon dioxide is a reactant in
photosynthesis.
What happens if the carbon dioxide concentration is increased above a certain threshold? - answer-
further increases in the carbon dioxide concentration do not increase the rate of photosynthesis
because another factor (such as light intensity) is limiting the rate of reaction.
Increasing the temperature increases...
, Why? - answer- the rate of photosynthesis because more energy is provided.
What happens if the temperature is increased above 45°c,? - answer- the enzymes that catalyse
(speed-up) the reaction begin to denature (not work anymore).
This causes the rate of the reaction to drop sharply until it stops altogether.
What is the limiting factor for photosynthesis in winter? - answer- temperature
What is the limiting factor for photosynthesis in mineral-deficient soil? Why? - answer- if
plants are grown in mineral-deficient soil, they may not absorb enough minerals to produce lots of
chlorophyll.
In this case, chlorophyll concentration can be the limiting factor.
What is the limiting factor for photosynthesis at night? - answer- light intensity
What is the limiting factor for photosynthesis in warm and bright conditions? - answer- carbon
dioxide concentration
Co2 concentration, light levels and temperature are all at optimum values.
What might be the limiting factor of rate of photosynthesis, and why? - answer- the
concentration of mineral ions in the soil is probably the limiting factor.
Chlorophyll absorbs light energy and the production of chlorophyll requires these mineral ions
(especially mg2+).
What happens if a farmer increases the lighting and heating in a greenhouse? - answer- increase
in rate of photosynthesis
Farming may become too expensive
Crops grow faster
