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 deeply interconnected.

• Diagnostic anatomy: Utilizes imaging technologies (e.g., x-rays, CT scans, MRI) and ultrasound to examine structures in a living body.

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

• Homeostasis: Refers to the body's ability to maintain a stable internal environment. Disease results from significant homeostatic imbalance.

• Microscopic anatomy: Studies structures not visible to the naked eye (e.g., cytology and histology).

• Physiology: Includes subdisciplines like cell physiology, systemic physiology, and pathological physiology.

Levels of Organization

• Chemical level: Atoms and molecules.

• Tissue level: Groups of similar cells working together.

• Organ level: Organs composed of different tissues.

• Organ system level: Organs with a common function.

• Organism level: The complete living being.

Life Functions

• Responsiveness, growth, reproduction, movement, metabolism.

• Metabolism: Includes catabolism (breakdown) and anabolism (synthesis).

• Homeostasis: Maintains internal conditions despite external changes.

Organ Systems

• Nervous system: Provides rapid communication and control.

• Endocrine system: Provides slower, longer-lasting regulation via hormones.

• Integumentary system: Protects and regulates body temperature.

• Cardiovascular system: Distributes blood, gases, nutrients, and hormones.

• Lymphatic system: Defends against infection and disease.

• Urinary system: Eliminates wastes and regulates fluid balance.

• Digestive system: Processes food and absorbs nutrients.

• Respiratory system: Exchanges gases between blood and air.

• Reproductive system: Produces offspring.

• Muscular system: Provides movement, support, and heat production.

• Skeletal system: Provides support, protection, and stores minerals.

Body Cavities and Anatomical Position

• Anatomical position: Standard reference; standing upright, palms forward.

• Terms for orientation: Anterior/posterior, superior/inferior, proximal/distal, and planes.

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

Chapter 2: The Chemical Level of Organization

Atoms, Elements, and Molecules

The chemical level of organization forms the foundation for all biological structures and processes.

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

• Elements: Substances composed of one type of atom. Major body elements: O, C, H, N, P, Ca.

• Molecules: Formed by chemical bonds.

• Ionic bonds: Transfer electrons; covalent bonds: Share electrons.

Acids, Bases, and Buffers

• Acids, bases, and salts dissolve into ions.

• pH scale: 0 (acidic) to 14 (basic); 7 is neutral.

• Buffers: Stabilize pH in body fluids.

Biomolecules

• Carbohydrates: Provide quick energy.

• Monosaccharides (e.g., glucose), disaccharides, polysaccharides.

• Lipids: Include fats, oils, phospholipids, steroids.

• Proteins: Composed of amino acids.

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

• Enzymes: Lower activation energy of reactions.

• Nucleic acids (DNA/RNA): Store genetic info.

• ATP: The energy currency of the cell.

Chapter 3: The Cellular Level of Organization

Cell Structure and Function

Cells are the structural and functional units of life. Their shape and size are suited to their specific functions.

• Plasma membrane: Maintains cell integrity; controls entry/exit.

• Membrane components: Lipids, proteins, carbohydrates.

• Transport mechanisms: Diffusion, facilitated diffusion, osmosis.

• Endocytosis: Engulfing particles (phagocytosis, pinocytosis, receptor-mediated).

• Exocytosis: Expels materials.

• Cytoskeleton: Provides shape and support; includes microfilaments, microtubules.

• Centrioles: Organize spindle fibers in mitosis.

• Cilia and flagella: Movement.

• Ribosomes: Make proteins.

• Rough ER: Protein processing; Smooth ER: Lipid synthesis.

• Golgi complex: Packages proteins.

• Lysosomes: Digest materials.

• Mitochondria: ATP synthesis.

• Nucleus: Contains DNA, chromatin, nucleolus.

• Gene expression: DNA transcription and translation.

• Cell cycle: Interphase (G1, S, G2), mitosis (PMAT), cytokinesis.

• Apoptosis: Programmed cell death.

Chapter 4: The Tissue Level of Organization

Types of Tissues

Tissues are groups of cells with similar structure and function. There are four basic types in the human body.

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

• Connective tissue: Supports, protects, binds other tissues.

• Muscle tissue: Produces movement.

• Nervous tissue: Transmits signals.

Connective Tissue Details

• Cell types: Fibroblasts, adipocytes, macrophages, mast cells.

• Matrix: Ground substance, fibers (collagen, elastic, reticular).

• Cartilage: Hyaline, elastic, fibrocartilage.

• Bone: Compact and spongy; highly vascularized.

• Blood: Plasma + formed elements (RBCs, WBCs, platelets).

• Areolar and adipose: Loose CT; tendons and ligaments: dense CT.

Muscle and Nervous Tissue

• Muscle tissue: Skeletal (voluntary), cardiac (involuntary, striated), smooth (involuntary, non-striated).

• Nervous tissue: Neurons (transmit signals), neuroglia (support cells).

• Neuron parts: Dendrites (input), soma (cell body), axon (output).

Chapter 5: The Integumentary System

Structure and Function of Skin

The integumentary system includes the skin, hair, nails, and associated glands. It serves as the body's first line of defense.

• Skin = epidermis + dermis; below is hypodermis.

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

• Layers: Epidermis (stratum basale, spinosum, granulosum, lucidum (thick skin), corneum).

• Dermis: Papillary layer (areolar CT) and reticular layer (dense irregular CT).

• Hair: Shaft, root, follicle, arrector pili muscle.

• Nails: Keratinized plates; lunula, eponychium, nail bed, matrix.

• Glands: Sebaceous (oil), sudoriferous (sweat: eccrine/apocrine), ceruminous (earwax), mammary (milk).

• Skin color: Determined by melanin, carotene, and hemoglobin.

• Conditions: Cyanosis (blue), jaundice (yellow), erythema (redness).

Chapter 6: Osseous Tissue and Bone Structure

Bone Structure and Function

Osseous tissue forms the rigid framework of the body, providing support, protection, and enabling movement.

• Functions: Support, movement, protection, mineral storage, blood formation.

• Matrix: Collagen (flexibility) + calcium salts (hardness).

• Bone types: Long, short, flat, irregular, sesamoid.

• Gross anatomy: Diaphysis, epiphyses, metaphysis, medullary cavity.

• Compact bone: Osteons (Haversian system).

• Spongy bone: Trabeculae, bone marrow in canal.

• Periosteum (outer) and endosteum (inner) linings.

• Ossification: Intramembranous (flat bones), endochondral (long bones).

• Growth plates (epiphyseal plates) allow longitudinal growth.

Chapter 7: The Axial Skeleton

Axial Skeleton Components

The axial skeleton consists of the skull, vertebral column, and thoracic cage, providing central support and protection for vital organs.

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

• Cranial bones: Frontal, parietal, occipital, temporal, sphenoid, ethmoid.

• Facial bones: Maxilla, palatine, nasal, zygomatic, lacrimal, vomer, mandible.

• Sutures: Coronal, sagittal, squamous, lambdoid.

• Hyoid: Does not articulate with other bones.

• Vertebral column: 7 cervical, 12 thoracic, 5 lumbar, sacrum, coccyx.

• Curvatures: Cervical/lumbar (concave), thoracic/sacral (convex).

• Vertebrae: Body, vertebral arch, spinous process, transverse process.

• Intervertebral discs: Annulus fibrosus + nucleus pulposus.

• Thoracic cage: Sternum (manubrium, body, xiphoid) and 12 pairs of ribs.

• Ribs: True (1-7), false (8-12), floating (11-12).

• Thoracic vertebrae: Costal facets for rib attachment.

• Key landmarks: Foramen magnum, sella turcica, mastoid process.

• Common injuries: Scaphoid fracture, stress fractures in athletes.