Photosynthesis: A Brief Notes On Photosynthesis

Photosynthesis

What organisms perform it? Most plants, algae, and cyanobacteria perform photosynthesis; such organisms are called photoautotrophs. What organelle is needed if it is a eukaryotic cell? The organelle needed to perform photosynthesis in a eukaryotic cell is the chloroplast. Chloroplasts contain chlorophyll, the primary pigment used in photosynthesis, and other molecules that function in the photosynthetic production of food.

Light Reactions Where do they occur? Light reactions take place in the thylakoid membranes of the chloroplast. In detail describe what occurs in photosystem II -

Short version: Photosystem II is one of two light-capturing units in a chloroplast 's thylakoid membrane. Photosystem I absorbs photons of wavelength of 680 nm. Light energy is captured by chlorophyll and transferred into high energy electrons; Water is broken up into Oxygen and Hydrogen Ions and Electrons; Electrons are sent to electron transport chain.

Makes ATP and uses electrons from light.

Long Version:

The Calvin cycle takes place in the stroma of the chloroplasts. Carbon fixation:

Short version: During carbon fixation each CO2 molecule is incorporated, one at a time, by attaching it to a five-carbon sugar, ribulose bisphosphate (RuBP) to form a 6 carbon molecule. The 6 carbon molecule splits to form two molecules of 3-phosphoglyceric acid (3-PGA).

Long version: In the stroma, in addition to CO2, two other components are present to initiate the light-independent reactions: an enzyme called ribulose bisphosphate carboxylase (RuBisCO) and three molecules of ribulose bisphosphate (RuBP). RuBP has five atoms of carbon, flanked by two phosphates. RuBisCO catalyzes a reaction between CO2 and RuBP. For each CO2 molecule that reacts with one RuBP, two molecules of 3-phosphoglyceric acid (3-PGA) form. 3-PGA has three carbons and one phosphate. Each turn of the cycle involves only one RuBP and one carbon dioxide and forms two molecules of