Biological Processes and Organ Functions

Key Life Processes of Living Things

  • Definition of Living Things: An organism is defined by its ability to perform the following life processes:
    • Movement: Ability to move either from place to place or through changes in their own body parts.
    • Reproduction: The process of producing offspring. All living organisms can reproduce.
    • Growth: Increase in size and mass, typically through cellular division and growth.
    • Nutrition: Requirement for substances that provide energy and materials for growth. Organisms need nutrients to sustain life.
    • Respiration: Process through which organisms convert nutrients into energy, commonly involving oxygen intake.
    • Excretion: The removal of waste substances that are produced by metabolism.
    • Sensitivity: The ability to respond to environmental stimuli.

Organisms vs Non-Organisms

  • Examples of Organisms: Cow, goldfish, daffodil, mouse, octopus.
  • Examples of Non-Organisms: Car, chair, coal, rock, Sun, robot.

Reproduction и Nutrition

  • Animal Nutrition: Animals must consume food.
  • Plant Nutrition: Plants manufacture their own food through photosynthesis but also require minerals from the soil.

Organ Functions

Human Organs

  • Heart: Pumps blood throughout the body.
  • Lungs: Facilitate respiration by exchanging oxygen and carbon dioxide.
  • Liver: Processes nutrients and detoxifies harmful substances.
  • Kidneys: Remove waste from the blood and produce urine.
  • Stomach: Breaks down food through mechanical and chemical processes.

Plant Organs

  • Leaves: Main site of photosynthesis; capture sunlight for energy.
  • Roots: Anchor the plant and absorb water and nutrients from the soil.
  • Stem: Transports nutrients and provides structural support.

Tissues

  • Definition: A tissue is a group of similar cells working together to perform a specific function.
  • Types of Tissues in Humans:
    • Muscle Tissue: Responsible for movement.
    • Nerve Tissue: Involved in transmitting signals.
    • Fat Tissue: Stores energy and provides insulation.

Plant Tissues

  • Xylem Tissue: Transports water from roots to leaves.
  • Phloem Tissue: Transports nutrients and food produced by photosynthesis.
  • Root Hair Tissue: Specialised for water absorption from the soil.

Cells

  • Animal Cells: Have components such as the nucleus, cytoplasm, and cell membrane.
  • Plant Cells: Feature additional components like chloroplasts (for photosynthesis) and rigid cell walls.

Organ Systems

  • Definition: An organ system consists of a group of organs working together to carry out a specific function.
  • Examples in Humans:
    • Circulatory System: Transports blood and nutrients.
    • Digestive System: Breaks down food and absorbs nutrients.
    • Nervous System: Processes information and controls actions.
  • Examples in Plants:
    • Water Transport System: Moves water from roots to leaves.

Investigation Suggestion

  • To determine water loss from a leaf’s upper or lower surface:
    • Set up two leaves, one facing up and the other facing down.
    • Measure the water loss over a period to compare which side loses more water due to evaporation.

Summary

  • Understanding life processes, organ functions, tissue roles, and the organization of cells into systems is critical for distinguishing living organisms from non-living matter.