Overview
This lecture provides a comprehensive review of human anatomy and physiology, covering all major body systems, key terminology, structural features, and essential functions for healthcare entrance exams.
Anatomical Terminology & Body Orientation
- Anatomical terms define body parts and positions (ex: cranial=head, thoracic=chest, femoral=thigh).
- Key directions: anterior (front), posterior (back), superior (towards head), inferior (towards feet), medial (toward midline), lateral (away from midline), proximal (closer to trunk), distal (further from trunk).
- Body planes: sagittal (divides left/right), frontal (divides front/back), transverse (divides top/bottom).
Respiratory System
- Main structures: nose, mouth, throat, larynx, trachea, bronchi, bronchioles, alveoli, lungs.
- Function: exchanges oxygen and carbon dioxide; maintains blood pH.
- Breathing in: diaphragm contracts, thoracic volume increases, air flows in; breathing out: diaphragm relaxes, air flows out.
- Disease factors: asthma, pneumonia, bronchitis, smoking, pollution, allergies.
Cardiovascular System
- Components: heart (4 chambers), blood vessels (arteries, veins, capillaries), blood.
- Heart: right/left atrium and ventricle separated by septum.
- Blood flow: heart → arteries → capillaries (exchange) → veins → heart → lungs.
- Key terms: systole (heart contracts), diastole (heart relaxes).
- Electrical conduction: SA node, AV node, bundle of His, bundle branches, Purkinje fibers.
- Functions: transports O₂ and nutrients, removes waste, maintains blood pressure and temperature, transports hormones.
Digestive System
- Structures: mouth, esophagus, stomach, small intestine, large intestine, rectum; accessory organs: teeth, tongue, liver, gallbladder, pancreas.
- Function: digests food, absorbs nutrients, eliminates waste.
- Main enzymes/hormones: gastrin, cholecystokinin (CCK), secretin, insulin, glucagon, bile.
Nervous System
- Divisions: central (brain, spinal cord) and peripheral (nerves).
- Neuron structure: cell body, dendrites, axon, myelin sheath, synapses.
- Sensory (afferent) vs. motor (efferent) neurons; somatic (voluntary) vs. autonomic (involuntary) systems.
Muscular System
- Types: skeletal (voluntary, striated), cardiac (heart, involuntary), smooth (organs, involuntary).
- Function: movement by contraction; nerves stimulate muscles to contract.
Reproductive System
- Male: testes, epididymis, vas deferens, seminal vesicles, prostate, penis (produce and deliver sperm).
- Female: ovaries, fallopian tubes, uterus, vagina, vulva (produce eggs, support fetus).
- Hormonal regulation: GnRH, FSH, LH, testosterone, estrogen, progesterone.
Integumentary System
- Main parts: skin (epidermis, dermis, subcutaneous), hair, nails, sweat glands.
- Functions: protection, temperature regulation, sensation, excretion.
Endocrine System
- Glands: pituitary, thyroid, parathyroid, thymus, adrenal, pancreas, testes, ovaries.
- Functions: hormone secretion for growth, metabolism, reproduction, mood.
- Hormone types: lipid-based, non-polar fat-soluble, water-soluble.
- Homeostasis via positive (oxytocin) and negative (insulin) feedback.
Urinary System
- Structures: kidneys (cortex, medulla), ureters, bladder, urethra.
- Function: filters blood, regulates fluid/electrolyte balance, removes waste (urine).
- Nephron: filtration unit (includes glomerulus and tubule).
- Kidneys produce erythropoietin for red blood cell production.
Immune System
- Defenses: innate (skin, mucous membranes, inflammatory response) and adaptive (lymphatic system, WBCs, antibodies).
- Cell types: phagocytes, antigen-presenting cells, helper/cytotoxic T cells, B cells, memory cells.
- Immunity: passive (antibodies from another) vs. active (your own antibodies).
Skeletal System
- Bone types: long (limbs), short (wrists, ankles), flat (ribs, sternum), irregular (vertebrae).
- Bone structure: compact, spongy, marrow (produces blood cells).
- Joints held by ligaments; muscles attach via tendons.
- Works with muscular system for movement.
Key Terms & Definitions
- Anterior — front of the body
- Posterior — back of the body
- Alveoli — air sacs in lungs for gas exchange
- Systole — heart contraction phase
- Diastole — heart relaxation phase
- Neuron — basic nerve cell
- Hormone — chemical messenger released by glands
- Nephron — kidney’s functional unit for filtration
- Antigen — substance provoking immune response
Action Items / Next Steps
- Review anatomical terminology and body planes.
- Memorize major organ structures and their functions within each body system.
- Study key hormones and their roles.
- Prepare for exam questions on system interrelationships (e.g., cardiovascular and urinary).
- Complete assigned readings or practice questions as directed by your instructor.