Green plants contain
chlorophyll which makes them
green-they absorb light for
photosynthesis
The glucose is used in respiration, or
converted into starch and stored.
Oxygen is produced as a by-product.
Temperature, carbon dioxide concentration
and light intensity are factors that can limit
the rate of photosynthesis.
Chemical change
Photosynthesis takes place in
leaf cells. These contain
chloroplasts, which are tiny
objects containing chlorophyll.
Plants need to take in a number of
elements to stay alive. The most
important are: carbon, hydrogen,
oxygen
Sometimes photosynthesis is
limited by the concentration of
carbon dioxide in the air. Even if
there is plenty of light, a plant
cannot photosynthesise if there
is insufficient carbon dioxide.
Glucose + oxygen → carbon dioxide + water (+ energy)
Respiration releases energy for cells
from glucose. This can be aerobic
respiration, which needs oxygen, or
anaerobic respiration, which does not.
During exercise, the breathing rate and
heart rate increase. During hard
exercise an oxygen lack may build up.
Aerobic respiration happens all the
time in the cells of animals and
plants. Most of the reactions
involved happen inside mitochondria,
tiny objects inside the cytoplasm
of the cell. The reactions are
controlled by enzymes.
Plants make amino acids from
sugars, nitrates and other nutrients.
Glucose is a sugar.These amino acids
are then compacted into larger
molecules - proteins
Respiration needs to be high
speed in exercise to maintain
oxygen