Process:- Various functions carried out by living beings; which are necessary
to maintain and continue life are called life process.
the life processes in living beings:-
Nutrition: The process by which an organism takes food and utilizes it is
Need of nutrition: Organisms need energy to perform various activities.
The energy is supplied by the nutrients. Organisms need various raw materials
for growth and repair. These raw materials are provided by nutrients.
Nutrients: Materials which provide nutrition to organisms are called
nutrients. Carbohydrates, proteins and fats are the main nutrients and are
called macronutrients. Minerals and vitamins are required in small amounts and
hence are called micronutrients.
Types of Nutrition:
(a) Autotrophic Nutrition: The mode of nutrition in which an organism
prepares its own food is called autotrophic nutrition. Green plants and
blue-green algae follow the autotrophic mode of nutrition.
(b) Heterotrophic Nutrition: The mode of nutrition in which an organism
takes food from another organism is called heterotrophic nutrition. Organisms;
other than green plants and blue-green algae follow heterotrophic mode of
nutrition. Heterotrophic nutrition can be further divided into two types, viz.
saprophytic nutrition and holozoic nutrition.
(1) Saprophytic Nutrition: In saprophytic nutrition; the organism
secretes the digestive juices on the food. The food is digested while it is
still to be ingested. The digested food is then ingested by the organism. All
the decomposers follow saprophytic nutrition. Some insects; like houseflies;
also follow this mode of nutrition.
(2) Holozoic Nutrition: In holozoic nutrition; the digestion happens
inside the body of the organism, i.e. after the food is ingested. Most of the
animals follow this mode of nutrition.
Life Processes: Plant Nutrition
Life Processes: Animal Nutrition
Life Processes: Respiration
Life Processes: Transport in Plants
Life Processes: Transport in animals
Life Processes: Test Your knowledge1
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Life Processes: MCQ1
Life Processes: MCQ2
Life Processes: MCQ3
Life Processes: MCQ4