Plant and Animal Organ Systems Revision

Levels of Biological Organisation

  • Organisms are structured according to specific levels of complexity:

    • Cell: The basic unit of life.

    • Tissue: A group of similar cells working together.

    • Organ: A structure composed of different tissues.

    • Organ system: A group of organs working together.

    • Organism: The complete living being.

  • Standard order: Cell→Tissue→Organ→Organ system→OrganismCell \rightarrow Tissue \rightarrow Organ \rightarrow Organ \, system \rightarrow Organism

Human Organ Systems and Functions

  • Brain: Controls the body; part of the nervous system.

  • Heart: Pumps blood around the body; part of the circulatory system.

  • Lungs: Main organs of the respiratory system for exchanging oxygen (O2O_2) and carbon dioxide (CO2CO_2).

  • Stomach: Begins the digestion of food.

  • Kidneys: Remove wastes from the blood.

  • Diaphragm: Assists in changing the volume of the chest cavity during breathing.

  • Arteries: Blood vessels that generally possess thick, muscular walls.

The Respiratory and Circulatory Systems

  • Inhalation Pathway: Nose/Mouth→Trachea→Bronchi→Bronchioles→AlveoliNose/Mouth \rightarrow Trachea \rightarrow Bronchi \rightarrow Bronchioles \rightarrow Alveoli.

  • Gas Exchange: Blood carries oxygen from the lungs to body cells and returns carbon dioxide to the lungs to be exhaled.

  • Red Blood Cells: Highly adapted for efficient oxygen transport.

  • Heart Anatomy: Includes the right atrium, right ventricle, left atrium, left ventricle, aorta, vena cava, pulmonary artery, pulmonary vein, and valves.

  • Systemic Circulation:

    • Deoxygenated blood enters the right side of the heart.

    • Blood is sent to the lungs for oxygenation.

    • Oxygenated blood returns to the left side of the heart.

    • The left side pumps oxygenated blood to the rest of the body.

Plant Biology and Photosynthesis

  • Plant Cell Organelles: Cell membrane, Nucleus, Mitochondria, Chloroplast, Cell wall, and Vacuole.

  • Photosynthesis: The process where plant leaves use energy from sunlight to convert carbon dioxide from the air and water from the soil into food.

  • Equation for Photosynthesis: Carbon dioxide+Water→sunlightGlucose+Oxygen\text{Carbon dioxide} + \text{Water} \xrightarrow{\text{sunlight}} \text{Glucose} + \text{Oxygen}

  • Roots: Responsible for absorbing water and minerals from the soil.

  • Stem: Provides structural support and serves as a transport pathway.

Plant Transport Systems

  • Xylem: Transports water and minerals; movement is generally upwards from the roots.

  • Phloem: Transports glucose (food) throughout the plant.