Reactants for photosynthesis
carbon dioxide + water
products of photosynthesis
glucose + oxygen
Word equations for photosynthesis
carbon dioxide + water —> glucose + oxygen
What energy is required for photosynthesis?
Light
Where does photosynthesis take place?
Chloroplasts
What substance is in chloroplasts enables photosynthesis?
Chlorophyll
What are the limiting factors of photosynthesis?
light intensity, carbon dioxide concentration and temperature
How is glucose used in plants?
Respiration, cellulose production, amino acids production, stores
How is glucose used in respiration?
Energy is transferred from glucose
How is cellulose used?
To make cell walls
How are amino acids used by plants?
Make proteins
Other than amino acids, what else is used in production of proteins?
Nitrate ions
What forms is glucose stored as?
lipids and starch
Where are lipids stored in plants?
seeds
Where is starch stored in plants?
roots, stems, leaves
When are starch stores used?
When photosynthesis isn't happening
Give 2 examples of when starch stores are used.
night, winter
What is the required investigation into limiting factors?
Effect of light intensity on rate of photosynthesis of pondweed
What is the independent variable for the pondweed practical?
light intensity
How is the light intensity changed?
moving the pondweed away from the lamp
How is the light intensity measured? (in this practical)
cm away from the lamp
What is the dependent variable in the pondweed practical?
rate of photosynthesis
How is the rate of photosynthesis measured? (in this practical)
bubbles of CO2 released per minute
What are the control variables for the pondweed practical?
temperature, measuring period, lamp, pondweed
What is the relationship between light intensity and distance?
light intensity α 1/ d²
respiration
the process of transferring energy from the break down of glucose
Where does respiration happen?
mitochondria
When does respiration happen?
all the time
What are the 2 types of respiration?
aerobic and anaerobic
aerobic respiration
respiration using oxygen
Equation for aerobic respiration
glucose + oxygen → water + carbon dioxide
Equation for anaerobic respiration in animals
glucose → lactic acid
Equation for anaerobic respiration in plants
glucose
Which type of respiration is used during exercise?
Anaerobic (animal)
Why is anaerobic respiration less used during exercise?
to supply enough oxygen to the body
Why does your heart rate increase when you exercise?
to get oxygen to cells and carbon dioxide out of the body faster
Lactic acid
unoxidised (not fully broken down) glucose
What does a build up of lactic acid cause?
muscle fatigue
What happens after you stop anaerobically respiring?
oxygen debt
oxygen debt
the amount of oxygen required to break down lactic acid produced during anaerobic respiration
Why does your pulse remain high after exercise?
to fully oxidise lactic acid, remove carbon dioxide, transport lactic acid to the liver
What happens to lactic acid in the liver?
converted back to glucose
What is the equation for anaerobic respiration (plants)?
glucose (yeast) → ethanol + carbon dioxide