Anatomy and Physiology Overview

Levels of Organisation

• Chemical Level: Atoms combine to form molecules, which are the building blocks of cells.
• Cellular Level: Cells are the basic unit of life, composed of various organelles that perform specific functions.
• Tissue Level: Groups of similar cells work together to perform a specific function; four main tissue types exist.

Cellular Organelles

• Nucleus: Contains DNA and regulates gene expression, playing a key role in cell growth and reproduction.
• Mitochondria: Powerhouse of the cell that produces ATP through aerobic respiration.
• Endoplasmic Reticulum (ER):
  • Rough ER has ribosomes for protein synthesis.
  • Smooth ER synthesizes lipids and detoxifies certain chemicals.
• Golgi Apparatus: Modifies, sorts, and packages proteins and lipids for secretion or use within the cell.
• Ribosomes: Sites of protein synthesis, can be free-floating or attached to the rough ER.

Protein Production Steps

• Transcription: DNA is transcribed into mRNA in the nucleus.
• Translation: mRNA is translated into a polypeptide chain (protein) at ribosomes in the cytoplasm.
• Post-Translational Modification: The polypeptide undergoes modifications in the ER and Golgi apparatus.

Cell Membrane Structure

• Composed of a phospholipid bilayer with hydrophilic heads (facing outward) and hydrophobic tails (facing inward).
• Proteins embedded in the bilayer facilitate transport and communication.

Transport Mechanisms

• Diffusion: Movement of molecules from an area of higher concentration to an area of lower concentration, driven by concentration gradient.
• Osmosis: Passive movement of water across a semipermeable membrane towards a higher solute concentration.
• Facilitated Diffusion: Movement of molecules across a membrane via specific transport proteins, without energy use.
• Active Transport: Moves molecules against their concentration gradient, requiring ATP energy.
• Cytosis: Process of engulfing large particles or volumes; includes endocytosis and exocytosis.

Tissue Classification

• Four main types of tissues:
  • Epithelial Tissue: Covers surfaces, forms barriers; characterized by cellularity and polarity.
  • Connective Tissue: Provides support and anchors organs; includes bone, blood, and adipose tissue.
  • Nervous Tissue: Transmits nerve impulses; composed of neurons and supporting glial cells.
  • Muscular Tissue: Facilitates movement; types include skeletal, cardiac, and smooth muscle.

Properties and Locations of Tissues

• Epithelial Tissue: High cellular density, avascular, found lining organs and body cavities.
• Connective Tissue: Variable vascularity; includes bone, cartilage, and blood; supports and connects other tissues.
• Nervous Tissue: Locations include the brain, spinal cord, and nerves; enables communication and processing of information.
• Muscular Tissue: Ranges from voluntary (skeletal) to involuntary (cardiac and smooth); allows for movement and contraction.

Structure-Function Relationship

• Tissues' structural features are directly related to their specific functions, such as epithelial cells being tightly packed for protection or muscle fibers being elongated for contraction.

This quiz covers the foundational concepts of human body organization, including chemical, cellular, and tissue levels. Participants will explore the functions of cellular organelles, the steps of protein production, and various transport mechanisms like diffusion and osmosis. Additionally, a diagram of the cell membrane will be required.