Anatomy and Physiology Overview

Anatomy and Physiology

• Anatomy refers to the structure of body parts and their interrelationship.
• Microscopic anatomy focuses on structures too small to be seen with the naked eye.
• Developmental anatomy studies the growth and changes in anatomical and physiological features throughout life.
• Physiology examines how body parts function and collaborate to sustain life.
• Normal body temperature is approximately 98.7°F (37°C).

Homeostasis

• Homeostasis maintains a relatively stable internal environment despite external changes.
• Negative feedback reduces physiological effects, such as regulating blood sugar and body temperature.
• Positive feedback enhances physiological responses, notably during labor contractions and blood clotting.

Anatomical Terminology

• Superior: towards the head
• Inferior: away from the head (also known as caudal)
• Anterior: towards the front (also called ventral)
• Posterior: towards the back (also called dorsal)
• Medial: towards the midline
• Lateral: away from the midline

Chemistry Fundamentals

• Energy is the capacity to do work; it exists in four forms: chemical, mechanical, electrical, and electromagnetic.
• The First Law of Thermodynamics states energy cannot be created or destroyed but can be transformed.
• D₂O is an isotope used in tracking excretion and carbon dating.
• Radioisotopes have the same chemical formula but different structural formulas, useful in imaging as staining agents.

Biological Molecules

• Water is cohesive due to hydrogen bonding, serving as a universal solvent with high heat capacity and vaporization point.
• pH measures the potential of hydrogen ions; buffers stabilize pH levels by converting strong acids/bases into weaker forms.
• Monosaccharides include glucose, fructose, and galactose; disaccharides include sucrose, lactose, and maltose; polysaccharides consist of glycogen, starch, and cellulose.
• Functions of lipids include energy storage, insulation, and organ protection; key types include phospholipids and steroids.

Cell Theory

• Cell theory posits that the cell is the smallest unit of life, all organisms consist of cells, and cells arise from pre-existing cells.
• Principle of Complementarity suggests that structure and function are interrelated.
• Basic components of a cell include the plasma membrane, cytoplasm, and nucleus.

Extracellular Materials

• Types of extracellular fluids include blood plasma, interstitial fluid, and cerebrospinal fluid.
• Cellular secretions encompass substances like saliva, mucus, and gastric juice.
• The extracellular matrix is primarily composed of the intercellular 'glue'.

Plasma Membrane

• Composed of phospholipids, glycolipids, and cholesterol, ensuring stability and selective permeability.
• Transport across the membrane can be passive or active:
  • Passive transport requires no energy and includes diffusion and osmosis.
  • Active transport involves energy input (e.g., Na/K pumps).
  • Vesicular transport methods include endocytosis (into cells) and exocytosis (out of cells).

Organelles

• Key organelles include the endoplasmic reticulum, mitochondria, Golgi apparatus, ribosomes, and lysosomes.
• Interphase is characterized by cell growth and preparation for division, while chromosomes form during prophase when chromatin condenses.

Nucleotide Pairing

• Nucleotide pairing includes A with T and C with G in DNA structure.