CSEP420 Cell Biology and Chemistry

Overview of Tissue and Cell Biology

  • Definition of Tissue: A group of specialised cells and intercellular material working together to perform specific functions.

Levels of Structural Organization

  • Chemical Level: Composed of atoms (e.g., C, H, O, N, P) and molecules (e.g., DNA).
  • Cellular Level: Focus on individual cells like smooth muscle cells.
  • Tissue Level: Formation of tissues such as smooth muscle tissue.
  • Organ Level: Combination of tissues to form organs, e.g., the stomach.
  • System Level: Groups of organs that work together (e.g., digestive system).
  • Organismal Level: The complete entity, the human body.

Types of Tissues in Humans

  • There are four main types of tissues:

    • Epithelial Tissue:
    • Acts as a barrier and regulates material movement.
    • Functions: selective barrier, secretory surface for product release.

    Epithelial Tissue

    • Connective Tissue (CT):

    • Most abundant and widely distributed tissue type.

    • Functions: protect and bind organs, store energy, provide immunity.

    • Types: tendons, ligaments, cartilage (e.g., sternum, trachea), bone, blood, adipose tissue.

    • Muscle Tissue:

    • Composed of elongated cells (myocytes) known as muscle fibers.

    • Functions: generation of force using ATP; high mitochondrial content --

      • Types of Muscle Tissue:
      • Skeletal Muscle
      • Cardiac Muscle
      • Smooth Muscle

    • Nervous Tissue:

    • Comprised of two main cell types:

      • Neurons: Specialized for conducting impulses, analyzing information, storing memories, and directing responses.
      • Neuroglia: Supportive cells in the nervous system.

Using a Microscope

  • Parts of a Microscope:

    • Arm, Stage, Objective Lens, Eye Piece Lens, Coarse and Fine Focus Knobs, Light Source, and Light Adjustment Knob.

  • Application of Microscopy:

    • Viewing Different Cells:
    • Onion Cells: Example of plant cells viewed under a microscope.
    • Human Cheek Cells: Animal cells, exemplified by photographs taken during class.
    • Blood Cells: Observed through microscopy techniques.
    • Free-living Cells: E.g., the Paramecium organism, exemplifying unicellular life forms.

Summary

  • Tissues consist of specialized cells grouped together for specific functionalities, such as protection, movement, and signaling. Understanding how to use a microscope is essential for viewing these tissues and their cellular components in detail.

Learning Goals

  • Learning Goal Concept Map: Next session will involve discussing and completing a concept map related to learning goals, encouraging self-belief and goal-oriented thinking.