Anatomy and Physiology of the Human Cell

Introduction

• Anatomy: Study of form and structure of an organism.
• Physiology: Study of processes and functioning of living organisms.
• Pathophysiology: Study of how disease affects normal functioning (covered in another video).

Basic Structures of the Cell

• Cell Membrane:

  • Semi-permeable structure.
  • Allows nutrients to enter and waste to exit.
  • Maintains cell shape; prevents organelles from spilling out.

• Cytoplasm:

  • Semi-fluid inside the cell.
  • Site for chemical reactions.

• Organelles:

  • Located within the cytoplasm.
  • Responsible for cell functions.

Organelles and Their Functions

• Nucleus:

  • Brain of the cell.
  • Controls functions and division.

• Nucleolus:

  • Located within the nucleus.
  • Important for cell reproduction.
  • Manufactures ribosomes.

• Ribosomes:

  • Composed of RNA and protein.
  • Manufactured in the nucleolus.
  • Serve as sites for protein synthesis (move from nucleus to cytoplasm).

• Chromatin:

  • Located in the nucleus.
  • DNA and protein in loose thread-like form.
  • Forms chromosomes for cell division (46 total chromosomes in each cell).

• Mitochondria:

  • Powerhouse of the cell.
  • Breaks down carbohydrates, fats, proteins to form ATP (energy of the cell).

• Golgi Apparatus:

  • Stack of membrane layers in cytoplasm.
  • Produces, stores, and packages secretions for discharge.

• Endoplasmic Reticulum (ER):

  • Transports materials in/out of nucleus.
  • Aids in protein synthesis/storage.
  • Smooth ER: Aids in fat metabolism, cholesterol synthesis, drug detoxification.
  • Rough ER: Regions with ribosomes for protein production.

• Lysosomes:

  • Digest proteins, fats, old cells, bacteria, foreign materials.
  • Important for immune system.

• Pinocytic Vesicles:

  • Pocket-like folds in cell membrane.
  • Allow proteins and fat molecules to enter the cell.
  • Form vacuoles or bubbles in cytoplasm.

Review

• Cell Membrane: Skin of the cell.
• Cytoplasm: Contains organelles.
• Organelles: Perform cell functions.
• Nucleus: Brain of the cell.
• Nucleolus: Creates ribosomes.
• Ribosomes: Sites for protein synthesis.
• Chromatin: DNA/protein threads form chromosomes.
• Mitochondria: Energy source for the cell.
• Golgi Apparatus: Packages secretions.
• Endoplasmic Reticulum: Transports materials.
• Lysosomes: Digest materials.
• Pinocytic Vesicles: Allow entry of proteins/fats.

Prepare for the next video on cell reproduction.