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In respiration, energy is released as a result of oxidation of food, whereas in photosynthesis it is stored up in a carbohydrate molecule. Oxygen is used in respiration whereas it is given out as a by-product in photosynthesis.

1. 230-250 molecules of chlorophyll make one quantasome.

2. Carbon dioxide enters the leaf through Stomata.

3. Xanthophyll is Yellow coloured pigment.

4. The conversion of physical energy of light into chemical energy by the chloroplast is called Photophosphorylation.

5. Calvin cycle was proposed by Melvin Calvin.

The immediate product of photosynthesis is Glucose.

1. The process of photosynthesis is an oxidation and reduction process in which water is oxidized (to release O₂ ) and CO₂ is reduced to form sugar. It consists of two successive series of reactions.

2. The first reaction requires light and is called Light reaction. 

3. Second reaction does not require light and is called Dark or Blackman reaction. 

4. Of the two reactions, the former is a photochemical reaction, while the latter is a biochemical reaction.

1. Chemically chlorophyll molecule consists of two parts head of tetrapyrrole the porphyrin ring and a long hydrocarbon tail called phytol attached to the porphyrin group. 

2. Both chlorophyll-a and chlorophyll-b are similar in their molecular structure, except that the methyl group (-CH) in chlorophyll-a is replaced with an aldehyde group (-CHO) in chlorophyll-b. 

3. Carotenoids are lipid compound present universally in almost all the higher plants and several microorganisms. 

4. They are usually red, orange, yellow, brown, and are associated with chlorophyll. They are of two types – the carotenes and xanthophylls. 

5. The carotenes (C₄OH₅ ) are orange red and xanthophylls contain oxygen. 

6. The light energy absorbed by the carotenoids is transferred to chlorophyll-a to be utilized in photosynthesis. 

7. All photosynthetic plants have these pigments that absorb light between the red and blue region of the spectrum. 

8. Carotenoids found mainly in higher plants, absorb primarily in the violet to blue regions of the spectrum. 

9. They not only absorb light energy and transfer it to chlorophyll but also protect the chlorophyll molecule from photo-oxidation. Xanthophylls (C₄OH₅6O₂ ) are yellow pigments found in fruits and vegetables.

The correct answer is (C) redox

The correct answer is (A) green

The correct answer is (C) Green

Chloroplast contains chlorophyll which is used to trap the solar energy from the sunlight which falls on the leaf. This energy is used during photolysis to split the water molecule into hydrogen and oxygen.

The tissues and cells which contain chloroplasts are mainly the palisade parenchyma and spongy mesophyll cells of a green leaf.

The correct answer is (D) NADP

1. The light reaction is a reaction in which solar energy is trapped by chlorophyll and stored in the form of chemical energy as ATP and in the form of reducing power as NADPH₂ . 

2. Oxygen is evolved in the light reaction by splitting of water.

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

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.

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.

Solar energy is trapped by chlorophyll and stored in the form of chemical energy as ATP and in the form of reducing power as NADPH₂ . Oxygen is evolved in the light reaction by splitting of water. The components of light reaction are as follows:

Reaction centre:

1. The light absorbing pigments present in thylakoid membranes are arranged in clusters of chlorophyll and accessory pigments. 

2. P-680 and P-700 are the special type of chlorophyll molecules which form the reaction centres or photocentres. 

3. Solar energy is harvested by accessory pigments and other chlorophyll molecule and is passed on to the reaction centre. 

4. These (accessory pigments) are known as light harvesting or antenna molecule. Their function is to absorb light energy and transmit at a very high rate to the reaction centre where the photochemical reactions occur.