Anatomy & Physiology: Foundational Study Notes (Ch. 1–7)

Chapter 1: An Introduction to Anatomy and Physiology

Overview of Anatomy and Physiology

Anatomy is the study of the structure of the human body, while physiology explores how those structures function to support life. These disciplines are closely interconnected.

• Diagnostic anatomy: Utilizes imaging technologies (e.g., X-rays, CT scans, MRI) to visualize internal structures.

• Pathological anatomy: Examines anatomical changes that occur due to disease.

• Physiology: Focuses on how body parts work (e.g., cardiovascular physiology).

• Levels of organization: Chemical, cellular, tissue, organ, organ system, organism.

• Homeostasis: The body's ability to maintain a stable internal environment.

• Directional terms: Used to describe locations (e.g., superior, inferior, anterior, posterior).

• Body planes: Sagittal, frontal (coronal), transverse.

• Body cavities: Dorsal (cranial and vertebral) and ventral (thoracic and abdominopelvic).

Example: The heart is located in the thoracic cavity, medial to the lungs.

Chapter 2: The Chemical Level of Organization

Basic Chemistry Concepts

The chemical level of organization includes atoms, molecules, and chemical bonds that form the basis of all biological structures and functions.

• Atoms: Composed of protons, neutrons, and electrons.

• Major elements: Oxygen (O), Carbon (C), Hydrogen (H), Nitrogen (N).

• Water: Most important inorganic molecule; solvent, lubricant, temperature regulator.

• Acids, bases, and salts: Dissociate in water; pH scale measures acidity ($pH = - ext{log}[ ext{H}^+]$).

• Buffers: Maintain pH in body fluids.

• Macromolecules: Carbohydrates, lipids, proteins, nucleic acids.

• Carbohydrates: Provide quick energy; include monosaccharides, disaccharides, polysaccharides.

• Lipids: Include fats, phospholipids, steroids; important for energy storage and cell membranes.

• Proteins: Structural, enzymatic, transport, communication functions.

• Nucleic acids: DNA and RNA; store and transmit genetic information.

• ATP: The energy currency of the cell.

Example: Glucose ($C_6H_{12}O_6$) is a monosaccharide used for cellular energy.

Chapter 3: The Cellular Level of Organization

Cell Structure and Function

Cells are the structural and functional units of life. They perform all vital processes necessary for survival.

• Cell theory: All living things are composed of cells; cells arise from pre-existing cells.

• Plasma membrane: Selectively permeable barrier; composed of phospholipid bilayer.

• Organelles: Specialized structures (e.g., nucleus, mitochondria, ribosomes).

• Endocytosis/exocytosis: Processes for moving substances into/out of cells.

• Cell cycle: Includes interphase (growth, DNA replication) and mitosis (cell division).

• Protein synthesis: DNA → RNA → Protein (transcription and translation).

Example: Mitochondria generate ATP through cellular respiration.

Chapter 4: The Tissue Level of Organization

Types of Tissues

Tissues are groups of similar cells that perform specific functions. The four basic tissue types are epithelial, connective, muscle, and nervous tissue.

• Epithelial tissue: Covers surfaces, lines cavities, forms glands.

• Connective tissue: Supports, protects, binds other tissues; includes bone, cartilage, blood.

• Muscle tissue: Responsible for movement; includes skeletal, cardiac, and smooth muscle.

• Nervous tissue: Conducts electrical impulses; includes neurons and neuroglia.

Example: Simple squamous epithelium lines blood vessels for efficient diffusion.

Chapter 5: The Integumentary System

Structure and Function of Skin

The integumentary system includes the skin, hair, nails, and associated glands. It protects the body and regulates temperature.

• Skin layers: Epidermis (outer), dermis (middle), hypodermis (deepest).

• Functions: Protection, sensation, thermoregulation, vitamin D synthesis.

• Glands: Sebaceous (oil), sweat (eccrine/apocrine), mammary.

• Common injuries: Burns (classified by depth), cuts, infections.

Example: Melanin in the epidermis protects against UV radiation.

Chapter 6: Osseous Tissue and Bone Structure

Bone Structure and Function

Bones provide support, protection, movement, and mineral storage. They are dynamic tissues that undergo constant remodeling.

• Bone types: Compact (dense) and spongy (trabecular).

• Cells: Osteocytes (mature bone cells), osteoblasts (bone-forming), osteoclasts (bone-resorbing).

• Bone formation: Intramembranous and endochondral ossification.

• Hormones: Parathyroid hormone (PTH), calcitonin, vitamin D, growth hormone.

• Fractures: Classified as open/closed, greenstick, comminuted, spiral, transverse.

Example: Osteoporosis results from decreased bone mass and increased fracture risk.

Chapter 7: The Axial Skeleton

Components of the Axial Skeleton

The axial skeleton consists of the skull, vertebral column, and thoracic cage. It provides central support and protects vital organs.

• Skull: 22 bones (8 cranial, 14 facial).

• Vertebral column: 26 vertebrae (cervical, thoracic, lumbar, sacrum, coccyx).

• Thoracic cage: Sternum and 12 pairs of ribs.

• Common injuries: Skull fractures, herniated discs, rib fractures.

Example: The atlas (C1) and axis (C2) vertebrae allow head rotation.