Biology Answer the following questions

Carbon fixation occurs in the stroma by series of enzyme catalyzed steps. The enzymes that catalyze the dark reactions of carbon fixation are located outside the thylakoids.

Formation of ATP in the chloroplasts in presence of light is called photophosphorylation, light

1. Together with P-680 they form Photosystem – II.
2. Likewise, P-700 forms Photosystem – I along with pigment molecule which absorbs light at or below 700 nm.

In absorption spectrum, absorption of different wavelengths of light pigments can be measured by spectrophotometer.

In stroma of a chloroplast.

When the light source is turned off, the high energy electrons return rapidly to their normal low energy orbitals as the excited molecule reverts to its original stable condition, called the ground state.

A molecule that has absorbed a photon is in energy rich excited state. An excited state of an atom means that the valence electron has moved from its ground state orbital to high energy orbital.

A certain minimum quantity of energy a photon must have to boost an electron is called quantum energy.

In this experiment, Hill cultured isolated chloroplasts in a medium containing C02 free water, haemoglobin and ferric compound.

Absorption and action spectra

Atmosphere contains only about 0.03 percent C02 by volume.