8. Photosynthesis Flashcards
What controls the reactions in photosynthesis?
Enzymes.
What does photosynthesis allow plants to do?
Make their own food.
What is light energy trapped by?
Chlorophyll.
Where is chlorophyll found?
Chloroplasts.
What compound contains the chemical elements carbon (C), Hydrogen (H) and oxygen (O) combined using energy?
Carbohydrate.
What raw materials does the production of carbohydrate food require to be available to supply the necessary chemicals?
Water and carbon dioxide.
What are the reactants of photosynthesis?
Light energy, water, carbon dioxide and chlorophyll.
What are the products of photosynthesis?
Glucose, oxygen and water.
During photosynthesis molecules of what combine with hydrogen from water?
Carbon dioxide.
What does the reaction of photosynthesis require the presence of to form sugar?
Chlorophyll and light energy.
What is the food product of photosynthesis?
Sugar.
What are the two stages of photosynthesis?
The light-dependent stage (consisting of several light dependent reactions) and the temperature-dependent stage (carbon fixation).
During the series of light reactions light energy is trapped by Chlorophyll and converted to what?
Chemical energy in the form of energy- rich ATP.
What is the ATP regenerated from?
ADP + Pi.
Some energy is also used during the light dependent stage to split what?
Water into hydrogen and oxygen.
What happens as a result of the light dependent stage?
Oxygen is released as a by-product and diffuses out of the plant and the hydrogen and ATP are formed and used during the carbon fixation.
Where does carbon fixation occur within the cell?
Chloroplasts.
What does carbon fixation consist of?
Several enzyme controlled reactions in the form of a cycle.
During carbon fixation, what combines with what to form sugar?
Carbon (from carbon dioxide) with Hydrogen from the light-dependent stage.
What supplies the energy needed to drive the process of carbon fixation?
ATP.
Sugar from photosynthesis is broken down by what to supply the plant with energy?
Respiration.
What activities is the energy that the sugar from photosynthesis supplies the plants with used for?
Energy requiring processes such as cell division and reproduction.
Some of the remaining glucose molecules become linked into long chains and packed together to form what?
Starch grains.
Where are starch grains found?
The cells cytoplasm.
What is the purpose of starch grains in a plant?
It is the plants food storage and can be converted back to sugar when energy is required.
Other glucose molecules are built into long chains of what?
Cellulose.
What is the purpose of cellulose in a plant?
They are gathered together to form the fibres needed to build cell walls.
What type of carbohydrate is a starch grain called?
A storage carbohydrate.
What type of carbohydrate is cellulose called?
A structural carbohydrate.
What non-carbohydrates can carbohydrates, produced during photosynthesis, also be converted to?
Fats and proteins.
What is additionally required to make proteins from carbohydrates?
Chemicals such as nitrate. These chemicals are absorbed from the soil solution by the plants root hairs.
What factors can effect photosynthetic rate?
Light intensity, carbon dioxide concentration, water availability and temperature.
