Class 10 Science Chapter 5: Life Processes – NCERT Solutions Notes Life Processes is a core biology chapter in Class 10 Science. It explains the basic functions that keep living organisms alive, such as nutrition, respiration, transportation, and excretion. It is highly important for both exams and conceptual understanding. These notes are structured for clear revision and NCERT-based preparation. Key Concepts Life Processes Life processes are the basic functions performed by living organisms to maintain and sustain life. Main life processes: Nutrition Respiration Transportation Excretion 1. Nutrition Nutrition is the process by which organisms obtain and use food for energy and growth. Types of Nutrition Autotrophic nutrition (plants) Heterotrophic nutrition (animals) Autotrophic Nutrition Plants make their own food using sunlight, carbon dioxide, and water. Process: Photosynthesis 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂ (in presence of sunlight and chlorophyll) Human Digestive System Steps: Ingestion Digestion Absorption Assimilation Egestion 2. Respiration Respiration is the process of releasing energy from food. Types: Aerobic respiration (with oxygen) Anaerobic respiration (without oxygen) Aerobic Respiration C₆H₁₂O₆ + O₂ → CO₂ + H₂O + Energy Anaerobic Respiration Occurs in absence of oxygen (e.g., yeast, muscle cells). Human Respiratory System Air pathway: Nose → Trachea → Bronchi → Lungs → Alveoli Alveoli help in gas exchange. 3. Transportation Transportation is the process of carrying materials inside the body. In Humans Blood Components: Plasma RBC (oxygen transport) WBC (immunity) Platelets (clotting) Heart 4 chambers: 2 atria, 2 ventricles Pumps blood throughout the body Double Circulation Blood passes through the heart twice in one cycle. In Plants Transport system: Xylem → transports water Phloem → transports food 4. Excretion Excretion is the removal of waste products from the body. Human Excretory System Main organs: Kidneys Ureters Urinary bladder Urethra Nephron Basic functional unit of kidney. Functions: Filtration Reabsorption Urine formation NCERT Important Questions (Concept Based) Why is diffusion insufficient in large organisms? Because their body size is large and needs a transport system. What is photosynthesis? Process of making food using sunlight, CO₂, and water. What is double circulation? Blood passes through the heart twice in one cycle. Important Diagrams to Revise Human digestive system Human respiratory system Heart structure Nephron Plant transport system Why this chapter is important This is one of the most important biology chapters. It is frequently asked in exams in: Diagrams Process explanation NCERT-based questions Reasoning answers Final Revision Tip Focus on: Photosynthesis equation Digestion steps Heart and blood flow Nephron diagram Difference between xylem and phloem