Photosynthesis

Photosynthesis

Photosynthesis is the process where plant cells transform the sunlight energy, carbon dioxide and water into chemical potential energy
Produces glucose
Produces oxygen as a waste product
6CO2+6H2O → C6H12O6+6O2+6H2O
Chloroplasts
1. Site of photosynthesis in cell
2. Large disk shaped organelles with a complicated internal structure with: Outer and inner membranes, Grana and Stroma
  1. Stroma is a liquid filled interior
  2. Grana are made up of a system of membrane structures called thylakoids. The thylakoids are arranged into stacks called grana (plural)/granum (singular). Grana are connected by stroma lamellae.
3. Chloroplasts use special pigments (chlorophyll and carotenoid) to absorb light energy. These pigment molecules are embedded in the thylakoid membrane.
4. The internal structure of chloroplasts provides sites for the complex series of reactions involving 2 main stages
  1. Light Dependent
    1. Chlorophyll in thylakoids absorb light energy to make ATP & split water into hydrogen & O2.
    2. Occurs in the Grana
    3. Light energy is captured and transferred into ATP and NADPH which are used to provide energy for stage 2
  2. Light Independent stage
    1. CO2 & hydrogen enter biochemical cycle to produce glucose – using ATP from Light Phase.
    2. Occurs in the Stroma
    3. Hydrogen from light dependent phase combines with carbon dioxide to form glucose.Energy from ATP is needed for these complex reactions
Factors affecting photosynthesis
1. Temperature
2. Light intensity
3. CO2 Concentration
Important because
1. Plants, as autotrophs, make their own food and do so from sunlight, carbon dioxide and water through a process called photosynthesis.
2. Animals are heterotrophs and must consume other living things to gain the energy and nutrients they need to live. Without plants we would have no food and no oxygen to breathe.

Next up

Description

Resource summary

Similar

	Created by Rebecca Wilson almost 11 years ago