GCSE Biology Paper 1 - Photosynthesis

What is the photosynthesis equation ?

carbon dioxide + water ——-> glucose + oxygen

What is transpiration ?

Transpiration is the loss of water by evaporation from plants

What does the xylem do?

The xylem transports water and minerals up the stem from the roots in one direction only

What does the phloem do ?

The phloem transports sugars/glucose produced from the leaves up and down the stem

Is photosynthesis an endo or exothermic reaction ?

Endothermic

What are the three limiting factors of photosynthesis?

• increase in light intensity

• increase in carbon dioxide

• Increase in temperature

How do plants use glucose ?

• Respiration

• Lipids

• Cellulose

• Protein synthesis

• Starch

What solution is used in photosynthesis required practical ?

Sodium hydrogen carbonate solution

how long should the piece of pond weed be in the photosynthesis required practical ?

5cm

If you don’t use an L.E.D light bulb what should you put in between the test tube and the ordinary bulb ?

A beaker of water

In the photosynthesis required practical what is the dependent variable ?

Number / volume of oxygen bubbles

In the photosynthesis required practical what is the independent variable ?

Distance of the bunk and light intensity

In the photosynthesis required practical what is the control variable ?

Pond weed and sodium hydrogen carbonate solution

What do you have to let the bulb do before the practical ?

Acclimatize

What can you change in the practical ?

The colour of the light this is by a colour filter or a colour changing L.E.D

How do you count the oxygen bubbles produced ?

By using a funnel and a measuring cylinder