Life Processes

Life Processes Overview

  • Key Organelles: Nucleus, Ribosomes, Plasma Membrane, Endoplasmic Reticulum, Golgi Apparatus, Mitochondria, Vesicles

  • Organization Level: Cells → Tissues → Organs → Organ Systems → Organism

  • Living organisms consist of well-structured cells and tissues, which need repair and maintenance due to environmental impact.

Essential Life Processes

  • Life Processes: Nutrition, Respiration, Excretion, Growth, Movement, Sensitivity, Reproduction.

Characteristics of Living Organisms

  • Movement: Ability to move or parts can move to find resources or adapt to sunlight.

  • Respiration: Chemical reactions in cells that break down nutrients to release energy.

  • Sensitivity: Detecting and responding to environmental changes.

  • Growth: Permanent increase in size, measurable by mass or cell count.

  • Reproduction: Creating more organisms.

  • Excretion: Removal of metabolic waste including toxic substances.

  • Nutrition: Intake of materials for development, involves energy production for growth and repair.

Energy and Nutrition

  • Nutrition: Transport of energy from outside to inside, required for growth and metabolic maintenance.

  • Autotrophs: Organisms like plants that produce their own food using sunlight and inorganic materials.

    • Photosynthesis: Conversion of CO2 and water into carbohydrates using sunlight and chlorophyll.

  • Heterotrophs: Organisms like animals that depend on other living beings for food.

Photosynthesis Process

  1. Absorption of light energy by chlorophyll.

  2. Conversion of light energy into chemical energy.

  3. Splitting of water molecules.

  4. Reduction of CO2 into carbohydrates.

Nutrition in Different Organisms

  • Amoeba: Engulfs food using pseudopodia, forms food vacuoles, digests food internally.

  • Paramecium: Uses cilia to capture food at a specific location.

Respiration

  • Involves the oxidation of food to release energy, with some organisms using oxygen and others not.

  • Gas exchange in plants occurs through stomata, regulating CO2 and O2 levels.

Transportation in Organisms

  • Transportation: Movement of water and nutrients across the organism's body.

    • In Plants: Xylem carries water and minerals from roots; Phloem distributes photosynthetic products.

Excretion

  • Excretion: Removal of metabolic wastes.

    • Unicellular organisms: Diffusion of wastes into surrounding water.

    • Multicellular organisms: Specialized organs for waste removal (e.g., kidneys in humans).

Plant Excretion

  • Waste products like oxygen, CO2, and excess water are disposed of primarily via transpiration, storage in vacuoles, and through the soil.