Comprehensive Study Guide: Anatomy and Physiology Exam Revision

Introduction to Anatomy & Physiology

Relationship Between Anatomy and Physiology

Anatomy is the study of the structure of body parts, while physiology is the study of the function of those parts. Understanding both is essential for comprehending how the human body operates as an integrated whole.

• Anatomy: Focuses on the physical structure (e.g., organs, tissues, cells).

• Physiology: Explores how those structures work and interact.

• Example: The heart's anatomy (chambers, valves) relates directly to its function (pumping blood).

Levels of Organization in Living Organisms

• Chemical Level: Atoms and molecules

• Cellular Level: Cells and their organelles

• Tissue Level: Groups of similar cells

• Organ Level: Two or more tissue types

• Organ System Level: Organs working together

• Organism Level: The complete living being

Basic Tissues and Body Systems

• Four Basic Tissues: Epithelial, connective, muscle, nervous

• 11 Major Organ Systems: Integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, reproductive

Anatomical Terms and Body Organization

• Body Sections: Sagittal, coronal, transverse planes

• Body Regions: Axial (head, neck, trunk), appendicular (limbs)

• Relative Positions: Superior/inferior, anterior/posterior, medial/lateral, proximal/distal

• Major Body Cavities: Dorsal (cranial, vertebral), thoracic, abdominopelvic

Homeostatic Control

• Homeostasis: Maintenance of a stable internal environment

• Negative Feedback: Response reduces or shuts off original stimulus (e.g., body temperature regulation)

• Positive Feedback: Response enhances original stimulus (e.g., blood clotting)

Chemical, Cellular, and Tissue Level

Atoms, Molecules, and Chemical Reactions

• Atom: Smallest unit of matter, composed of protons, neutrons, electrons

• Molecules and Compounds: Atoms combine via chemical bonds (ionic, covalent, hydrogen)

• Chemical Reactions: Synthesis, decomposition, exchange reactions

• Enzymes: Biological catalysts that speed up metabolic reactions

Inorganic vs. Organic Compounds

• Inorganic: Usually lack carbon (e.g., water, salts, acids, bases)

• Organic: Contain carbon and hydrogen (e.g., carbohydrates, lipids, proteins, nucleic acids)

Water and pH

• Water: Universal solvent, high heat capacity, essential for life

• pH: Measure of hydrogen ion concentration; $pH = -\log_{10}[H^+]$

• Importance: Enzyme activity and cellular processes depend on pH

Cell Structure and Function

• Plasma Membrane: Selective barrier, composed of phospholipid bilayer with embedded proteins

• Organelles: Nucleus (genetic control), mitochondria (energy), ER (protein/lipid synthesis), Golgi apparatus (modification/packaging), lysosomes (digestion)

• Genetic Code: DNA sequence that determines protein synthesis

Cell Transport Mechanisms

• Diffusion: Movement of molecules from high to low concentration

• Osmosis: Diffusion of water across a semipermeable membrane

• Carrier-Mediated Transport: Uses membrane proteins to move substances

• Vesicular Transport: Endocytosis and exocytosis for large molecules

Tissues

• Epithelial Tissue: Covers surfaces, lines cavities, forms glands

• Connective Tissue: Supports, protects, binds other tissues (proper, fluid, supporting)

• Muscle Tissue: Movement (skeletal, cardiac, smooth)

• Nervous Tissue: Transmits electrical impulses

Integumentary & Skeletal System

Skin Structure and Function

• Epidermis: Outer layer, provides protection

• Dermis: Middle layer, contains blood vessels, nerves, glands

• Subcutaneous Layer: Fat storage, insulation

• Skin Color: Determined by melanin, carotene, hemoglobin

• Hair and Nails: Protection, sensation, formed from keratin

• Glands: Sebaceous (oil), sweat (eccrine, apocrine)

• Skin Repair: Involves inflammation, cell migration, proliferation, and maturation

• Aging: Thinner skin, reduced elasticity, slower healing

Skeletal System

• Functions: Support, protection, movement, mineral storage, blood cell production

• Bone Classification: By shape (long, short, flat, irregular, sesamoid, sutural)

• Bone Structure: Compact (dense) vs. spongy (cancellous)

• Bone Cells: Osteocytes, osteoblasts, osteoclasts, osteoprogenitor cells

• Axial Skeleton: Skull, vertebral column, thoracic cage

• Appendicular Skeleton: Limbs, pectoral and pelvic girdles

• Vertebral Column: Cervical (7), thoracic (12), lumbar (5), sacral (5 fused), coccygeal (4 fused)

• Thorax: 12 pairs of ribs (true, false, floating), sternum

• Pelvic Girdle: Ilium, ischium, pubis; male vs. female pelvis differences

Joints & Muscles

Joints

• Categories: Fibrous, cartilaginous, synovial

• Synovial Joints: Freely movable, contain synovial fluid

• Joint Structure: Articular cartilage, joint capsule, synovial membrane

• Shoulder and Elbow: Examples of synovial joints with specific movement capabilities

Muscle Tissue

• Skeletal Muscle: Voluntary movement, striated fibers

• Muscle Organization: Muscle → fascicle → fiber → myofibril → sarcomere

• Sarcomere: Functional unit of muscle contraction

• Neuromuscular Junction: Site where nerve stimulates muscle fiber

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

• Fascicle Arrangement: Parallel, convergent, pennate, circular

• Levers: First, second, third class; affect force and movement

• Muscle Naming: Based on location, shape, size, direction, number of origins, action

• Aging: Decreased muscle mass, strength, flexibility

Nervous System: Nerves, Spinal Cord, Brain, Senses

Nervous System Organization

• CNS: Brain and spinal cord

• PNS: Nerves outside CNS

• Neuron Structure: Cell body, dendrites, axon

• Neuroglia: Support cells (astrocytes, oligodendrocytes, Schwann cells, etc.)

Neural Function

• Action Potential: Electrical impulse along neuron

• Resting Membrane Potential: $V_m = -70\ \text{mV}$ (typical value)

• Synaptic Activity: Neurotransmitter release and binding

Spinal Cord and Nerves

• Structure: White matter (axons), grey matter (cell bodies)

• Meninges: Dura mater, arachnoid mater, pia mater

• Spinal Nerves: Emerge from segments, form plexuses

• Reflex Arc: Sensory input → integration → motor output

Brain and Senses

• Brain Regions: Cerebrum, cerebellum, diencephalon, brainstem

• Cerebral Cortex: Sensory, motor, association areas

• Sensory Receptors: Detect specific stimuli (mechanoreceptors, thermoreceptors, etc.)

Special Senses & Endocrine System

Special Senses

• Smell (Olfaction): Olfactory epithelium, olfactory bulb

• Taste (Gustation): Taste buds, cranial nerves

• Vision: Eye structures (cornea, lens, retina), optic nerve

• Hearing & Equilibrium: Ear structures (external, middle, inner), cochlea, vestibular apparatus

Endocrine System

• Hormones: Chemical messengers (amino acid, protein, lipid derivatives)

• Regulation: Negative feedback controls secretion

• Key Glands: Hypothalamus, pituitary, thyroid

• Blood Glucose Regulation: Insulin and glucagon maintain homeostasis; disruption leads to diabetes

Cardiovascular System: Arteries, Veins, Heart

Arteries and Veins

• Arteries: Carry blood away from heart; types include elastic, muscular, arterioles

• Veins: Return blood to heart; have valves to prevent backflow

• Aorta: Main artery; branches supply body regions

• Clinical Terms: Hypertension (high blood pressure), aneurysm (vessel wall bulge)

Heart Structure and Function

• Chambers: Right/left atria, right/left ventricles

• Layers: Pericardium (fibrous, serous), myocardium, endocardium

• Conducting System: SA node, AV node, bundle branches, Purkinje fibers

• Coronary Circulation: Supplies heart muscle; occlusion leads to myocardial infarction

Blood, Lymphatic System, and Immunity

Blood Components and Function

• Components: Plasma (~55%), red blood cells (~45%), white blood cells, platelets

• Red Blood Cells: Biconcave shape, contain hemoglobin for oxygen transport

• Blood Types: Determined by antigens (A, B, AB, O)

• White Blood Cells: Immune defense

Lymphatic System and Immunity

• Structures: Lymph nodes, lymph vessels

• Relationship: Lymphatic system returns fluid to circulatory system

• Innate Immunity: Phagocytes, inflammation, complement

• Adaptive Immunity: Antigens, antibodies, T-cells, B-cells

• Antibody Action: Neutralize pathogens, promote phagocytosis

Respiratory System

Structure and Function

• Primary Functions: Gas exchange, protection of exchange surfaces

• Upper Respiratory Organs: Nose, pharynx, larynx

• Larynx: Air passage, sound production

• Lungs: Lobes, alveoli (site of gas exchange)

• Respiration: External (lungs/blood), internal (blood/tissues)

• Gas Transport: Hemoglobin carries O2 and CO2

• Aging: Reduced elasticity, decreased gas exchange

Digestive System and Metabolism

Digestive System

• Organs: Mouth, esophagus, stomach, small/large intestine, accessory organs (liver, pancreas, gallbladder)

• Stomach: Digestion, absorption

• Small Intestine: Major site of absorption; receives blood supply from mesenteric arteries

Metabolism

• Energetics: Study of energy flow and transformation in cells

• Cellular Respiration: Glycolysis, citric acid cycle, electron transport chain

• Lipid Metabolism: Breakdown and synthesis of fats

• Protein Metabolism: Amino acid breakdown and synthesis

Urinary & Reproductive System

Urinary System

• Organs: Kidneys, ureters, bladder, urethra

• Kidneys: Filter blood, form urine

• Nephron: Functional unit; filtration, reabsorption, secretion

Reproductive System

• Female: Ovaries, uterine tubes, uterus, vagina, external genitalia

• Ovarian/Uterine Cycles: Regulate reproduction

• Male: Testes, ducts, accessory glands, penis