Life Process Class 10 Science
Notes
Nutrition in Plants and Animals – Life
Processes.
Nutrition: The process by which an organism takes
food and utilizes it, is called nutrition.
Need for Nutrition: Organisms need the energy to
perform various activities. 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.
Modes of Nutrition
1. Autotrophic Nutrition.
2. Heterotrophic Nutrition.
Autotrophic Nutrition – Life Processes.
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.
The organisms which carry out autotrophic nutrition
are called autotrophs (green plants).
Autotrophic nutrition is fulfilled by the process, by
which autotrophs intake CO2 and H2O, and convert
, these into carbohydrates in the presence of
chlorophyll, sunlight is called photosynthesis.
Equation
Nutrition in Plants: Green plants prepare their own food.
They make food in the presence of sunlight. Sunlight provides
energy, carbon dioxide and water are the raw materials and
chloroplast is the site where food is made.
What is Photosynthesis?
Photosynthesis: The process by which green plants prepare
food is called photosynthesis.
During this process, the solar energy is converted into
chemical energy and carbohydrates are formed.
Green leaves are the main site of photosynthesis.
The green portion of the plant contains a pigment
chloroplast, chlorophyll (green pigment).
The whole process of photosynthesis can be shown by
the following equation:
, Raw Materials for Photosynthesis:
Sunlight
Chlorophyll: Sunlight absorbed by chloroplast
CO2: Enters through stomata, and oxygen (O2) is
released as a byproduct through stomata on the leaf.
Water: Water + dissolved minerals like nitrogen,
phosphorous etc., are taken up by the roots from the
soil.
How do raw materials for photosynthesis become available to
the plant?
Water comes from the soil, through the xylem tissue
in roots and stems.
Carbon dioxide comes in the leaves through stomata.
Site of Photosynthesis: Chloroplast in the leaf. Chloroplast
contains chlorophyll (green pigment)
Main Events of Photosynthesis:
Absorption of light energy by chlorophyll.
Conversion of light energy into chemical energy +
splitting (breaking) of water into hydrogen and
oxygen.
Reduction of CO2 to carbohydrates.
Sunlight activates chlorophyll, which leads to splitting
of the water molecule.
The hydrogen, released by the splitting of a water
molecule is utilized for the reduction of carbon
dioxide to produce carbohydrates.
Oxygen is the by-product of photosynthesis.
Carbohydrate is subsequently converted into starch
and is stored in leaves and other storage parts.
Notes
Nutrition in Plants and Animals – Life
Processes.
Nutrition: The process by which an organism takes
food and utilizes it, is called nutrition.
Need for Nutrition: Organisms need the energy to
perform various activities. 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.
Modes of Nutrition
1. Autotrophic Nutrition.
2. Heterotrophic Nutrition.
Autotrophic Nutrition – Life Processes.
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.
The organisms which carry out autotrophic nutrition
are called autotrophs (green plants).
Autotrophic nutrition is fulfilled by the process, by
which autotrophs intake CO2 and H2O, and convert
, these into carbohydrates in the presence of
chlorophyll, sunlight is called photosynthesis.
Equation
Nutrition in Plants: Green plants prepare their own food.
They make food in the presence of sunlight. Sunlight provides
energy, carbon dioxide and water are the raw materials and
chloroplast is the site where food is made.
What is Photosynthesis?
Photosynthesis: The process by which green plants prepare
food is called photosynthesis.
During this process, the solar energy is converted into
chemical energy and carbohydrates are formed.
Green leaves are the main site of photosynthesis.
The green portion of the plant contains a pigment
chloroplast, chlorophyll (green pigment).
The whole process of photosynthesis can be shown by
the following equation:
, Raw Materials for Photosynthesis:
Sunlight
Chlorophyll: Sunlight absorbed by chloroplast
CO2: Enters through stomata, and oxygen (O2) is
released as a byproduct through stomata on the leaf.
Water: Water + dissolved minerals like nitrogen,
phosphorous etc., are taken up by the roots from the
soil.
How do raw materials for photosynthesis become available to
the plant?
Water comes from the soil, through the xylem tissue
in roots and stems.
Carbon dioxide comes in the leaves through stomata.
Site of Photosynthesis: Chloroplast in the leaf. Chloroplast
contains chlorophyll (green pigment)
Main Events of Photosynthesis:
Absorption of light energy by chlorophyll.
Conversion of light energy into chemical energy +
splitting (breaking) of water into hydrogen and
oxygen.
Reduction of CO2 to carbohydrates.
Sunlight activates chlorophyll, which leads to splitting
of the water molecule.
The hydrogen, released by the splitting of a water
molecule is utilized for the reduction of carbon
dioxide to produce carbohydrates.
Oxygen is the by-product of photosynthesis.
Carbohydrate is subsequently converted into starch
and is stored in leaves and other storage parts.
