Life Processes — Science Class 10 Notes (CBSE & HBSE)
Free NCERT Science notes for Life Processes (Class 10) on Siksha Sarovar, aligned to CBSE and Haryana Board (HBSE). This chapter is broken into 4 topics with clear explanations, formulas, solved examples and board-pattern practice — free to read, no sign-up required.
Board exam focus — Life Processes (CBSE & HBSE)
Focuses on the essential functions required for survival: Nutrition, Respiration, Transportation, and Excretion. CBSE emphasizes detailed biological mechanisms and diagrams; HBSE focuses on definitions and functional roles.
Nutrition: Autotrophic and Heterotrophic
Life processes are basic functions performed by living organisms to maintain their life on earth.
1. Autotrophic Nutrition (Plants)
Plants use Photosynthesis to make food.
- Equation: 6CO₂ + 12H₂O + Sunlight + Chlorophyll → C₆H₁₂O₆ + 6O₂ + 6H₂O
- Steps: Absorption of light energy, conversion to chemical energy, splitting of water, and reduction of CO₂ to carbohydrates.
2. Heterotrophic Nutrition (Animals)
- Holozoic: Complex food is taken in and broken down (e.g., Amoeba, Humans).
- Saprophytic: Feeding on dead matter (e.g., Fungi).
- Parasitic: Living on/inside host (e.g., Cuscuta, Ticks).
Human Digestive System:
Involves Ingestion, Digestion (Mouth, Stomach, Small Intestine), Absorption, Assimilation, and Egestion.
Respiration
The process of releasing energy from food is respiration. It involves the breakdown of glucose.
Types of Respiration:
- Aerobic: In presence of Oxygen. Glucose → Pyruvate (Cytoplasm) → CO₂ + H₂O + Energy (Mitochondria - 38 ATP).
- Anaerobic: Absence of Oxygen.
- In Yeast (Fermentation): Ethanol + CO₂ + Energy.
- In Muscle cells: Lactic acid + Energy (causes cramps).
Human Respiratory System:
Nostrils → Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Alveoli (Site of gas exchange).
Transportation
In Humans (Circulatory System):
- Heart: A muscular pumping organ. Humans have a 4-chambered heart to prevent mixing of oxygenated and deoxygenated blood.
- Blood: Transports food, oxygen, and waste. Consists of Plasma, RBCs, WBCs, and Platelets.
- Blood Vessels: Arteries (carry blood away from heart), Veins (towards heart), and Capillaries.
In Plants:
- Xylem: Transports water and minerals (Upward only via suction pressure).
- Phloem: Transports food/sucrose (Bidirectional - Translocation).
Excretion
Removal of harmful metabolic wastes from the body.
Human Excretory System:
A pair of Kidneys, Ureters, Urinary Bladder, and Urethra.
- Nephron: The structural and functional unit of the kidney. It filters blood and reabsorbs useful substances (glucose, amino acids).
Excretion in Plants:
- Oxygen/CO₂ via stomata.
- Excess water via Transpiration.
- Storing waste in leaves that fall off, or as resins and gums.
Frequently asked questions
Are these Life Processes notes free?
Yes — the Life Processes notes for Science (Class 10) on Siksha Sarovar are completely free to read, with no account required.
Do these notes follow CBSE and HBSE?
Yes. The Life Processes notes are NCERT-aligned and include guidance for both CBSE and Haryana Board (HBSE), with important questions and MCQs for revision.
What does the Life Processes chapter cover?
Concept explanations, key formulas and definitions, fully solved examples and board-pattern practice questions for Life Processes.