Question

Please explain the following questions:

- What is the Calvin Cycle and what does it do?

- What is the fluid mosiac model?

Answer 1

Calvin Cycle:

Calvin cycle is the set of chemical reactions (light-independent reactions) that take place in chloroplasts during the second stage of photosynthesis. It is also called as Calvin–Benson cycle.

RuBP : ribulose-1,5-bisphosphate

The Calvin cycle reactions were divided into three main stages i.e carbon fixation, reduction, and regeneration of the RuBP molecule.

In Carbon fixation a five-carbon carbon acceptor called RuBP (ribulose-1,5-bisphosphate) accepts one molecule of carbon dioxide to form a six-carbon molecule in the presence of RuBP carboxylase/oxygenase (Rubisco) .

In reduction the six-carbon molecule breaks into two equal parts which is glyceraldehyde-3-phosphate (G3P) with the help of ATP and NADPH molecules .

In regeneration Some G3P molecules becomes glucose, and others were recycled to regenerate the RuBP acceptor

Fluid mosiac model:

Fluid mosiac model explains the structural components of plasma membraneof the cell

The plasma membrane has two layers (a bilayer) of phospholipids in which the protein molecules are embedded.

Phospholipids consists of two components the head and two tails. The head is a phosphate molecule that is attracted to water (hydrophilic). The two tails are made up of fatty acids which repelled with wate (hydrophobic).

Proteins and substances such as cholesterol embedded in the bilayer, which gives the membrane the look like a mosaic.