Photosynthesis

Photosynthesis Photosynthesis is the process by which plants make glucose. This occurs during the day i.e. when there is light

Respiration Respiration is the process by which plants breakdown glucose to produce energy This occurs in all cells This occurs during the day and at night

Photosynthesis and respiration

Leaves are the site for photosynthesis and their structure is specialised for this role. They are thin and flat for rapid diffusion of gases They have a large surface area to trap sunlight. They have veins to transport substances to and from leaf. They have a waxy cuticle to minimise water loss A petiole holds up the leaf to trap sunlight

Chloroplasts contain chlorophyll which enables photosynthesis to proceed. Air spaces in the spongy mesophyll allow gases to diffuse rapidly They have stomata that let the gases in and out

The process of photosynthesis Carbon dioxide + water -> glucose and oxygen 6 CO2 + 6 H2O -> C6H12O6 + 6 O2

Limiting factors Amount of light Amount of carbon dioxide Temperature Amount of chlorophyll

Light and photosynthesis

Carbon dioxide and photosynthesis

Temperature and photosynthesis

Summary of environmental effects on photosynthesis and respiration

Role of the stomata

Stomata (cont.)

How guard cells work