Life processes are fundamental to the survival and functioning of living organisms, encompassing critical activities such as nutrition, respiration, circulation, and excretion. Through the "Life Processes Class 10 Notes," students will delve into the biological mechanisms that allow organisms to sustain homeostasis and carry out daily operations. By examining systems like digestion, respiratory pathways, blood transport, and waste removal, students will gain insights into how life is perpetuated. These notes provide a systematic framework for mastering essential concepts, vital for excelling in exams and applying biological knowledge to real-world contexts.
Life Processes
1. Life Processes:
Life processes are basic functions performed by living organisms to maintain life. These include nutrition, respiration, transportation, and excretion.
2. Nutrition:
a) Types of Nutrition:
- Autotrophic Nutrition: Organisms like plants prepare their own food by photosynthesis.
Equation: 6CO₂ + 6H₂O + Sunlight → C₆H₁₂O₆ (Glucose) + 6O₂. - Heterotrophic Nutrition: Organisms depend on other organisms for food. It includes holozoic, parasitic, and saprotrophic nutrition.
Example: Humans, animals.
b) Photosynthesis:
The process by which green plants synthesize food (glucose) from carbon dioxide and water using sunlight and chlorophyll.
Equation: 6CO₂ + 6H₂O + Sunlight → C₆H₁₂O₆ + 6O₂.
c) Steps of Nutrition in Humans:
- Ingestion: Taking in food.
- Digestion: Breaking down food into simpler substances.
Example: Starch → Maltose (by salivary amylase in the mouth). - Absorption: Absorbing digested food into blood.
- Assimilation: Utilization of absorbed food.
- Egestion: Removal of undigested food.
3. Respiration:
a) Types of Respiration:
- Aerobic Respiration: Occurs in the presence of oxygen.
Equation: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + Energy (ATP). - Anaerobic Respiration: Occurs in the absence of oxygen.
Equation (in yeast): C₆H₁₂O₆ → 2C₂H₅OH (Ethanol) + 2CO₂ + Energy.
b) Human Respiratory System:
Includes the nostrils, trachea, lungs, and diaphragm. Oxygen is inhaled, and carbon dioxide is exhaled.
- Gas Exchange: Oxygen from alveoli diffuses into the blood, and carbon dioxide from the blood diffuses into the alveoli to be exhaled.
4. Transportation:
a) Transportation in Humans:
- Blood: Blood transports oxygen, nutrients, and waste products. It contains red blood cells (RBCs), white blood cells (WBCs), platelets, and plasma.
- Heart: The heart pumps blood throughout the body. It has four chambers: two atria and two ventricles.
Pathway of Blood Flow:
Deoxygenated blood enters the right atrium → Right ventricle → Lungs (oxygenation) → Left atrium → Left ventricle → Body.
b) Transportation in Plants:
- Xylem: Transports water and minerals from roots to leaves.
- Phloem: Transports food (mainly sucrose) from leaves to other parts of the plant (translocation).
5. Excretion:
a) Excretion in Humans:
Excretion is the process of removing metabolic wastes from the body.
- Organs Involved: Kidneys, ureters, urinary bladder, and urethra.
- Kidneys: Filter blood to remove nitrogenous waste in the form of urea, which is excreted as urine.
b) Excretion in Plants:
Plants excrete waste products like oxygen and carbon dioxide through stomata. Some waste is stored in the form of resins and gums.
6. Human Circulatory System:
The circulatory system consists of the heart, blood vessels, and blood. It transports oxygen, nutrients, and waste products throughout the body.
Double Circulation:
In humans, blood passes through the heart twice during one complete cycle (pulmonary and systemic circulation).
- Pulmonary Circulation: Blood flows from the heart to the lungs and back.
- Systemic Circulation: Blood flows from the heart to the rest of the body and back.
7. Nutrition in Amoeba (Holozoic Nutrition):
Amoeba engulfs food using pseudopodia and forms a food vacuole. Digestion occurs inside the food vacuole, and nutrients are absorbed. Waste is egested through the cell membrane.
8. Nutrition in Plants:
- Plants use photosynthesis to convert light energy into chemical energy stored in glucose.
- Essential Nutrients: Nitrogen, phosphorus, potassium, etc., are absorbed from the soil for growth and development.
9. Lymphatic System:
The lymphatic system transports lymph (a fluid containing white blood cells) and helps in immunity and maintaining fluid balance in the body.
10. Artificial Kidney (Dialysis):
When kidneys fail, dialysis is used to remove waste products from the blood. It involves filtering blood through a machine (dialyzer).
Life Processes Class 10 Notes | Science Chapter 5 Class 10 Notes
Life processes are fundamental to the survival and functioning of living organisms, encompassing critical activities such as nutrition, respiration, circulation, and excretion. Through the "Life Processes Class 10 Notes," students will delve into the biological mechanisms that allow organisms to sustain homeostasis and carry out daily operations. By examining systems like digestion, respiratory pathways, blood transport, and waste removal, students will gain insights into how life is perpetuated. These notes provide a systematic framework for mastering essential concepts, vital for excelling in exams and applying biological knowledge to real-world contexts.
