Nutrition in plants

The processes which together perform the maintenance job of our body are called life processes
Nutrition, excretion, respiration, transportation, coordination all are essential for our survival

It is a process of intake and utilization of nutrients in various biological activities
==Nutrients-== the inorganic or organic matter obtained from the surroundings in order to synthesize body constituents and use them as a source of energy

It is a process to convert light energy into chemical energy by green parts of plants

Reaction-

      6CO² + 12H²O→ C⁶H¹²O⁶ + 6O² + 6H²O

Absorption of sunlight by chlorophyll
Conversion of light energy into chemical energy and break down of water molecules
Reduction of carbon dioxide to carbohydrates

Water- It is transported from roots by xylem tissue
Light- sun is the ultimate source of light energy
Carbon dioxide- plants get carbon dioxide from the atmosphere through the stomata present on the leaf surface
Chlorophyll- It is a green coloured pigment present in chloroplast which is responsible for the absorption of sunlight

### Factors affecting photosynthesis

Temperature- the rate of photosynthesis increases by increasing temperature up to 40 Celsius above this temperature the rate of photosynthesis decreases also low temperature in hibis photosynthesis the temperates assets for the synthesis by affecting the activity of enzyme the enzymes function of the specific range of temperature and by height temperature causes in activation
Carbon dioxide- CO2 present in low concentration of 0.03 in atmosphere atmosphere the rate of photosynthesis increasing by increasing CO2 concentration If temperature and light are not Limited very high concentration of Co2 becomes toxic to plants and inhibits photosynthesis
Water- it is an essential raw material for photosynthesis. the rate of photosynthesis lowers if plants are not adequately supplied with water. Under water deficient conditions, the stomata aperture closes to reduce water loss by transpiration, as a result, the entry of Co2 is also strong.
Light- it varies in intensity, quality and duration. Under low light intensity, the rate of photosynthesis is also low. Increase in light intensity causes increase in rate of photosynthesis up to a certain limit. The quality of light also affects photosynthesis. Green pigment that is chlorophyll absorbs mostly red and blue light and reflect green light. Therefore, photosynthesis high in blue and red light and does not occur in green light.

Plants take other raw materials like nitrogen, Phosphorus, iron and magnesium from soil. Nitrogen is an essential element used in synthesis of protein and other compounds. This is taken up in the form of inorganic nitrates or nitrite or it is taken up as organic compound which has been prepared by bacteria from atmospheric nitrogen.

## Stomata

they are tiny force present on the surface of leaf what is epidermis the opening their closing also matter is controlled by Guard cells

gaseous exchange takes place in the leaf through stomatal pores for photosynthesis
loss of excess water from the plant body is done through stomata by transpiration in the form of water bases

Opening and closing of stomatal pores

the opening and closing of stomatal pores is a function of guard cells. Guard cells swell when the water flows into them causing the stomatal pores to open. Similarly the pores closes if the Guard cells shrink i.e loses water
As large amount of water is lost through the stomata, the plant closes these pores when it does not require carbon dioxide for photosynthesis.

### How to desert plants perform photosynthesis if their stomata remains closed during the day?

In desert plants, the stomata is opened during night. During night desert plants absorb carbon dioxide and form intermediate. During day time is stomata is closed to prevent loss of water the use this store carbon dioxide sunlight and chlorophyll to perform photosynthesis.