Complexity of Life - Detailed Notes

COMPLEXITY OF LIFE

CELLS

• Cells are the basic unit of life.
• Cells are the smallest components that constitute a living organism.
• Organisms can be:
  • Unicellular: Made of one cell.
  • Multicellular: Made of multiple cells.
• Cells contain organelles, which are special molecules that perform specific functions to keep the cell alive.

The Hierarchy of Life

• A cell is the smallest functional unit capable of performing life's tasks.
• Living organisms can be single-celled or composed of numerous cells.
• In multicellular organisms, cells are specialized and depend on each other for survival.
• The specialization and interdependence of cells leads to a hierarchical organization characterized by structure and function:
  • CELL: The basic unit of life.
  • TISSUE: A group of specialized cells working together for a specific function.
  • ORGAN: A distinct structure made of different tissues that perform a specific function.
  • ORGAN SYSTEM: A collection of organs that carry out specific functions within an organism.
  • ORGANISM: A living entity that performs all life functions.

TISSUES

• Tissues are formed when cells combine.
• In biology, a tissue represents a cellular organizational level between cells and a complete organ.
• A tissue consists of similar cells performing a specific function.
• Example: Blood, which consists of red blood cells, white blood cells, platelets, and plasma.

ANIMAL TISSUES

• Examples of animal tissues mentioned:
  • Adipose tissue
  • Nervous tissue
  • Bone tissue
  • Cartilage tissue
  • Connective tissue
  • Blood
  • Epithelial tissue

PLANT TISSUES

• XYLEM: Water-carrying tube.
• PHLOEM: Food-carrying tube.

ORGANS

• Organs are formed when tissues combine.
• An organ is a group of tissues in a living organism adapted to perform a specific function.
• In higher animals, organs are grouped into organ systems.
• Example: The esophagus, stomach, and liver are organs of the digestive system.

ANIMAL ORGANS

• Examples of animal organs mentioned:
  • EYE
  • TOOTH
  • LUNG
  • BRAIN
  • HEART
  • STOMACH
  • LIVER
  • KIDNEY
  • SKIN
  • BOWELS

PLANT ORGANS

• Reproductive structures:
  • Function to make more plants.
  • Include flowers, fruit, cones, and seeds.
• Leaves:
  • The primary site of photosynthesis.
• Stems:
  • Support and elevate the leaves.
  • Transport water and nutrients between roots and shoots.
  • Store water and nutrients.
• Roots:
  • Anchor the plant.
  • Absorb minerals and water.
  • Store nutrients.

ORGAN SYSTEM

• An organ system is formed when organs work together.
• Organs carry out related processes and functions to keep an organism alive.
• Example: The heart and blood vessels work together to form the circulatory system.

ANIMAL SYSTEM

• THE CARDIOVASCULAR SYSTEM.
• Consisting of:
  • Jugular Vein
  • Carotid Artery
  • Heart
  • Aorta

PLANT SYSTEM

• Shoot System:
  • Functions:
    • Photosynthesis
    • Transport of food and water
    • Reproduction
    • Storage
    • Response
• Root System:
  • Functions:
    • Anchorage
    • Absorption of water and minerals
    • Transport of food and water
    • Reproduction
    • Storage
    • Response

ORGANISM

• An organism is the combination of functional systems.
• An organism is a living thing.