PHS: Edexcel SB6 Revision

Which of the following is the correct equation for PHOTOSYNTHESIS?

• CO₂ + light + H₂O --> O₂ + Sugar
• CO₂ + sugar + H₂O --> O₂ + light
• _O2 + light + H₂O --> CO₂ + Sugar
• CO₂ + O₂ + H₂O --> Light+ Sugar

The leaf has a shiny, waxy cuticle around it to

• increase the rate of photosynthesis
• attract more light
• control water loss
• stop carbon dioxide and oxygen gases escaping

The two structures that limit transpiration  are known as

• Guard cells and xylem
• Stomata and guard cells
• xylem and phloem
• stomata and phloem

Vascular tissue that transports water and minerals UPWARDS from a plant's roots is know as ______.

• Chlorophyll
• Phloem
• Stomata
• Xylem

causes plant cells to lengthen

• auxins
• cytokins
• ethylene

Why do conifer trees have needles?

• Needles also shed snow more easily and less likely to lose water in dry environments.

• Needles can be harmful to many predators that feed on the bark of these leaves.

• Needles create more surface area in order to create more photosynthesis.

Why do cacti have deep large roots?

• The deep root of the cacti allows it to resist rainfall.

• In order to help the cacti to be stable in windy conditions.

• absorb water that is deep in the ground.

What is meant by the 'dependent variable'?

• the variable that is changed

• the variable that is measured or observed

• the variable that is kept the same

Which of the following are adaptations of plants that grow in hot, dry areas? Select all that apply.

• thick cuticle

• needle shaped leaves

• spines instead of leaves

• stomata only open at night

What factors affect the rate of photosynthesis? Select all that apply.

• wind

• temperature

• carbon dioxide concentration

• light intensity