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Chloroplasts are green in colour due to the presence of a green colouring pigment called chlorophyll.

Vitamin A is required for proper vision. The chemical name of vitamin ‘A’ is Retinol

Photon is the smallest unit of light energy.

Answer is (A) Stomata

Photolysis of water was discovered by Robert Hill. Hence it is known as Hill’s reaction.

(C) Chloroplast

Photolysis of water: 

1. Photolysis of water Splitting of water molecule by light activated chlorophyll molecule is known as photolysis of water. 

2. Oxygen is released during (photosynthesis) photolysis of water.

Yes, solar energy transforms into chemical energy by the process of photosynthesis.

Yes, the materials which are essential for photosynthesis and the products formed are involved in the equation.

Calvin cycle: The cycle of reactions in fixation of carbon dioxide to glucose is called Calvin cycle

Yes. Photosynthesis needs the following raw materials. 

1. Sunlight, CO₂ water are external factors. 

2. Chlorophyll and enzymes are internal factors.

Plants having coloured leaves also carry out photosynthesis. The coloured leaves containing pigments pass on the energy of sunlight trapped by them to chlorophyll.

1. The upper surface comprising of the palisade parenchyma. 

2. The lower surface comprising of the spongy parenchyma. 

3. Palisade parenchyma contains more number of chloroplasts than the spongy parenchyma.

4. Thus the upper surface is more green and shiny than the lower ones.

Dark reactions:

The reactions that occur in both presence or absence of light are called dark reactions. The occurance of dark reaction is independent of light.

1. The internal walls of stomach has number of gastric glands. They secret gastric juice. 

2. It contains HCl and enzymes. 

3. HCl kills the bacteria present in the food and protects us from their harmful effects. 

4. And also denatures the proteins so that enzymes can act easily on them.

1. The part of the leaf, which could get light through the cut design turns to blue black showing the presence of starch. 

2. The remaining part of the leaf which did not get light, do not turn blue, indicating that starch is not prepared.

B) glucose, water and oxygen

Stroma : The fluid filled portion of chloroplast is called as stroma.

Chloroplast is formed by 3 membranes

The hydrogen of NADPH present in the stroma is the connecting substance between light reaction and dark reaction.

It is believed to be responsible for enzymatic reactions leading to the synthesis of glucose, which inturn join together to form starch

ATP and NADPH are required for the utilization of carbon dioxide and formation of glucose during photosynthesis.

Grana : The stacked sac like structures formed by the third layer of chloroplasts is called grana.

A series of chemical reactions occur in a very quick succession initiated by light and therefore the phase is technically called the photochemical phase.

The light reaction takes place in chlorophyll containing thylakoids called grana of Chloroplasts.

A) 1 – Outer membrane, 2 – Stroma, 3 – Grana

(D) Guard cell

1. Substances found in chloroplast, which capture sunlight are called photosynthetic pigments.

2. Two major kinds of chlorophyll are associated with thylakoid membranes. 

3. Chlorophyll – a (blue – green in colour) and chlorophyll – b (yellow – green); around 250 to 400 pigment molecules are grouped as light harvesting units in each granum. 

4. Such innumerable units in chloroplasts make them appear completely different from other organelles.

The end products of light reaction are O₂ , ATP and NADPH.

Pepsin is secreted into stomach.

ATP and NADPH formed at the end of the light reaction are called assimilatory powers

(A) ATP, NADPH

Food passes through oesophagus by wave likemovements called peristaltic movements and reaches the stomach.

Indigestion: Indigestion is a general term when there is difficulty in digesting food. Healthy people can usually avoid problems related to indigestion by:

1. Having simple, well balanced meals.

2. Eating them in a leisurely manner. 

3. Thoroughly masticating the food. 

4. Avoiding taking violent excercises soon after eating food. 

5. Drinking plenty of water and having regular bowel movements.

C) Oxidation of carbon to carbon dioxide

Amylase helps in the breakdown of complex carbohydrates to simple ones.

\(6CO_2+12H_2O\underset{chlorophyll}{\stackrel{light}{\longrightarrow}}C_6H_{12}O_6+6O_2+6H_2O\)

Answer is (B) H₂O

Food is moved to the cytosome by the movement of cilia which covers the entire surface of the cell where the food is ingested.

1. The three pairs of salivary glands in mouth are : 

i) Parotid glands 

ii) Submandibular glands and 

iii) Sublingual glands. 

2. The enzyme secreted by salivary glands is amylase (ptyalin).

A) Break down of water molecule by light

Answer is (B) Lipase

A) Grana of chloroplasts

C) Ingestion → digestion → absorption → defecation

The surface area in the small intestine is increased due to villi.

(B) Chlorophyll

1. The process of digestion occurs in the alimentary canal or digestive system.

2. During the process of digestion large complex macro molecules present in the food are converted to simple and small molecules.

3. Digestion provides the food material properly absorbed by the body.