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LIFE PROCESSES

Living organisms have some basic characterstics like

they move,grow, reproduce,response to stimuli,need food etc.

According to Biologist view living organism has movement of molecules and require repairing and maintaining of structure and molecules.

Introduction

Life processes include a) Nutrition b) Respiration c) Transportation d) Assimilation e) Excreation

What are life processes

The processes which are essential to sustain life are called Life Processes.

Life processes are needed to prevent damage and breakdown ( for maintenance) and to get energy.

In a simple form we can say

Life processes-Energy-Through nutrition-food sources are carbon based.

In single cell organisms simple diffusion takes place but in case of multi-cellular organisms ,various body parts have specialised in the functions they perform ( Division of labour).

NUTRITION

Autotrophic nutrition

Autotrophic nutrition involves the intake of simple inorganic materials from the environment and using an external energy source like sun to synthesise complex high- energy organic material.

• Raw Materials required for Photosynthesis are:

a) Water used in photosynthesis is taken up from the soil by the roots in terrestrial plants.

b) Other materials like nitrogen, phosphorus, iron and magnesium are taken up from the soil.

c) Nitrogen is an essential element used in the synthesis of proteins and other compounds. This is taken up in the form of nitrates and nitrites. d) Carbondioxide is taken from atmosphere through stomata.

6H₂O + 6CO₂ ----------> C₆H₁₂O₆+ 6O₂

• The following events occur during this process –

(i) Absorption of light energy by chlorophyll.

(ii) Conversion of light energy to chemical energy and splitting of water molecules into hydrogen and oxygen.

(iii) Reduction of carbon dioxide to carbohydrates.

• The carbohydrates which are not used immediately are stored in the form of starch.