The document outlines essential life processes necessary for survival, including movement, respiration, sensitivity, growth, reproduction, excretion, and nutrition, specifically focusing on nutrition in organisms. It differentiates between autotrophic and heterotrophic nutrition, detailing processes such as photosynthesis in plants and digestion in humans. Additionally, it explains respiration types and highlights the human respiratory system's function in gas exchange.

1. LIFE PROCESSES
Class 10 Science
~Shubhika Chenna

2. LIFE PROCESSES
The processes which maintains body functions and
necessary for survival are called life process.
• All the processes which together perform tasks to
maintain the body and keep the organism alive.
• There are seven essential processes in common:
movement, respiration, sensitivity, growth,
reproduction, excretion and nutrition.
• The four main processes are: -
-Nutrition
-Respiration
-Transportation/Circulation
-Excretion

3. NUTRITION
The process of taking nutrients from food is called
nutrition. It is a critical part of health and development.
Modes of Nutrition:
-Autotrophic
-Heterotrophic
Autotrophic- The organism which produce their own food
from simple inorganic material (water and carbon dioxide)
in the presence of sunlight. Ex: Plants, algae, bacteria.
Heterotrophic- The organism which depends upon
another organism to live. Ex: Human beings, Amoeba,
Animals.

4. NUTRITION IN
PLANTS
• Photosynthesis- The process in which green plants
convert simple inorganic material (water, carbon
dioxide) into complex organic material (6CO2 +
6H2O → C6H12O6 + 6O2 ) in the presence of
chlorophyll and sunlight.
• Order of Events:
- Absorption of light energy by chlorophyll.
- Conversion of light energy into chemical energy
and splitting of water molecules into Hydrogen and
Oxygen
- Reduction of Carbon dioxide into Carbohydrates.
• Chloroplasts- These are the small organelles found
in plant cell. It contains chlorophyll, which absorb
sunlight for photosynthesis.

5. HETEROTROPHIC NUTRITION
Saprophytes- They
obtain food from
dead or decaying
organic matter. Ex-
Bacteria, Fungi etc.
Parasitic- They
obtain food from
another organism
without killing them.
Ex- Mosquito,
Leeches, Ticks, Tice
etc.
Holozoic- The mode
of nutrition which
involves ingestion,
digestion, absorption
and assimilation of
liquid or solid organic
material. Ex-
Animals, Human
beings etc.

6. NUTRITION IN
HUMAN
• Mouth- Intake of food
• Teeth- Breaks the food
• Tongue- Tasting and rolling the food
• Glands- Saliva contains enzyme (salivary
amylase) that breaks down starch (food) to
simple sugar.
 Oesophagus
• Taking food from mouth to stomach by Peristaltic
movement.
• Stomach is large organ, it expands when food
enters it.
• Gastric Glands- It releases Gastric Juice which
contains ; HCL, Pepsin and Mucus.
• HCL- Makes medium acidic kill the harmful
bacteria of food.
• Pepsin- Breaks down proteins into amino acids.
• Mucus- Protects inner lining of stomach.

7.  Stomach
• It is a site of complete digestion.
• Liver- It produces Bile Juice and salt.
• Bile Juice- It makes the food alkaline (breaks down into
simpler).
• Bile salt- Breaks the large fat globules. This is called
emulsification.
• Gall bladder- Stores Bile juice and salt
• Pancreas: Tripsin- Break down protein into amino acid.
Lipase- It breaks down emulsified fat.
 Small Intestine
• Villi -Finger like projections
-Increase in surface area of absorption
-Supplies food to blood vessels
• Then blood vessels take the food to each cell of the
body

8.  Large Intestine
• Unabsorbed food is sent.
• Its walls absorb more water from the material.
• Rest of the material is removed from the body via
Anus.
This process starts in the long tube called the
Alimentary canal from mouth to anus.

9. RESPIRATION
The process in which cells of an organism obtains energy by consuming oxygen and glucose is called Respiration.
It involves breathing.
• There are two types: Aerobic- Producing energy in the presence of oxygen.
Anaerobic- Producing energy in the absence or lack of oxygen.
GLUCOSE
Anaerobic – Absence of Oxygen:
Ethanol (C2H5OH) + Carbon Dioxide + Energy
Ex: Yeast
Lack of Oxygen:
Lactic acid (C3H6O3 ) + Energy
Ex: Muscle cells
Presence of Oxygen:
Water + Carbon Dioxide + Energy
Ex: Living Beings (takes place in Mitochondria)

10. HUMAN
RESPIRATORTY
SYSTEM
• Oxygen is taken into the body through nose.
• The air is filtered by fine hairs present in the nose.
• From nose the air passed through the throat to lungs.
 In the Lungs:
The air passage divides into smaller and smaller tubes and
finally reach in the alveoli.
 Alveoli
• Balloon- like structures
• Provides a surface for exchange of gases.
• The walls of the alveoli connects with blood vessels.

11. • Then, oxygen dissolves in Haemoglobin from alveoli
and is carried from lungs to cells to all the body parts.
• The blood brings Carbon Dioxide from the cells
releases into Alveoli.