PAGE 1 • LIFE PROCESSES
What are Life Processes?
• Life processes are the basic activities that keep an organism alive and functioning.
• Main life processes in humans: Nutrition, Respiration, Transportation and Excretion.
• These processes work together to supply energy and remove wastes.
Nutrition
• Nutrition is the process by which organisms obtain food and use it for energy, growth and
repair.
• Autotrophic nutrition: Organisms make their own food, e.g. green plants.
• Heterotrophic nutrition: Organisms depend on other organisms for food, e.g. humans.
Quick Revision
• Food → energy + growth + repair
• Green plants → mainly autotrophic
• Humans → heterotrophic
Class 10 CBSE • NCERT-based Life Processes Notes • Page 1
, PAGE 2 • NUTRITION IN PLANTS
Photosynthesis
• Green plants prepare food using carbon dioxide + water in the presence of sunlight and
chlorophyll.
• Word equation: Carbon dioxide + Water → Glucose + Oxygen
• Glucose may be stored as starch.
Role of Stomata
• Stomata are tiny pores, mainly on leaves.
• They allow exchange of gases and also help in loss of water vapour through transpiration.
• Guard cells control the opening and closing of stomata.
Factors Needed
• Sunlight • Chlorophyll • Carbon dioxide • Water
Class 10 CBSE • NCERT-based Life Processes Notes • Page 2
What are Life Processes?
• Life processes are the basic activities that keep an organism alive and functioning.
• Main life processes in humans: Nutrition, Respiration, Transportation and Excretion.
• These processes work together to supply energy and remove wastes.
Nutrition
• Nutrition is the process by which organisms obtain food and use it for energy, growth and
repair.
• Autotrophic nutrition: Organisms make their own food, e.g. green plants.
• Heterotrophic nutrition: Organisms depend on other organisms for food, e.g. humans.
Quick Revision
• Food → energy + growth + repair
• Green plants → mainly autotrophic
• Humans → heterotrophic
Class 10 CBSE • NCERT-based Life Processes Notes • Page 1
, PAGE 2 • NUTRITION IN PLANTS
Photosynthesis
• Green plants prepare food using carbon dioxide + water in the presence of sunlight and
chlorophyll.
• Word equation: Carbon dioxide + Water → Glucose + Oxygen
• Glucose may be stored as starch.
Role of Stomata
• Stomata are tiny pores, mainly on leaves.
• They allow exchange of gases and also help in loss of water vapour through transpiration.
• Guard cells control the opening and closing of stomata.
Factors Needed
• Sunlight • Chlorophyll • Carbon dioxide • Water
Class 10 CBSE • NCERT-based Life Processes Notes • Page 2
