Comprehensive Anatomy & Physiology Final Exam Review Guide

Endocrine System

Overview of Hormones and Glands

The endocrine system regulates body functions through the secretion of hormones. Hormones are chemical messengers released into the bloodstream by endocrine glands, affecting distant target organs.

• Water-soluble hormones (e.g., peptides, catecholamines): Bind to cell surface receptors; act via second messengers.

• Fat-soluble hormones (e.g., steroids, thyroid hormones): Cross cell membranes; bind to intracellular receptors and directly influence gene expression.

• Tropic hormones: Hormones that regulate the activity of other endocrine glands (e.g., TSH, ACTH).

Pituitary Gland Structures

• Hypothalamus: Brain region controlling the pituitary gland.

• Infundibulum: Stalk connecting hypothalamus to pituitary.

• Posterior pituitary: Stores and releases hormones made by the hypothalamus (e.g., ADH, oxytocin).

• Anterior pituitary: Produces and releases its own hormones (e.g., GH, ACTH, TSH, LH, FSH, prolactin).

• Hypophyseal portal vein: Blood vessel system linking hypothalamus and anterior pituitary for hormone transport.

Major Pituitary Hormones and Their Effects

• Prolactin: Stimulates milk production in mammary glands.

• Growth hormone (GH): Stimulates growth, cell reproduction, and regeneration.

• ACTH: Stimulates adrenal cortex to release cortisol.

• TSH: Stimulates thyroid gland to produce thyroid hormones.

• FSH/LH: Regulate reproductive processes.

• ADH: Promotes water reabsorption in kidneys.

• Oxytocin: Stimulates uterine contractions and milk ejection.

Hormone Regulation and Feedback

• Negative feedback: The hypothalamic-pituitary axis uses negative feedback to maintain hormone levels within a physiological range.

Other Endocrine Glands and Hormones

• Thyroid hormones: Regulate metabolism, growth, and development.

• Parathyroid hormone: Increases blood calcium levels.

• Adrenal hormones: Aldosterone (Na+ retention), cortisol (stress response), epinephrine (fight-or-flight response).

• Pancreatic hormones: Insulin (lowers blood glucose), glucagon (raises blood glucose).

Diabetes Mellitus

• Polyuria: Excessive urination.

• Ketacidosis: Acidic blood due to ketone bodies.

• Polydipsia: Excessive thirst.

Other Hormones

• Histamine, CCK, Thymosin, Renin, Erythropoietin, Gastrin, Secretin: Each has specific roles in digestion, immune function, blood pressure, and red blood cell production.

Additional info: The endocrine system is covered in Ch. 16 of standard A&P textbooks.

Blood

Blood Composition and Functions

• Plasma: Liquid matrix of blood, contains water, proteins, nutrients, hormones, and waste products.

• Formed elements: Erythrocytes (RBCs), leukocytes (WBCs), and platelets.

• Hematocrit: Percentage of blood volume occupied by RBCs.

• Hemoglobin: Oxygen-carrying protein in RBCs; composed of globin chains and heme groups.

Blood Disorders

• Anemia: Reduced oxygen-carrying capacity of blood; types include hemorrhagic, iron deficiency, aplastic, pernicious, hemolytic, and sickle cell anemia.

• Polycythemia: Excess RBCs.

• Leukemia: Cancer of WBCs.

Blood Typing and Compatibility

Blood Type	Antigens Present
AB+	A, B, Rh
O-	None
A-	A
B-	B

Compatibility: Blood transfusions require matching antigens to prevent immune reactions.

White Blood Cells (WBCs)

• Neutrophils: Phagocytize bacteria.

• Eosinophils: Combat parasites, modulate allergic responses.

• Basophils: Release histamine in inflammation.

• Monocytes: Become macrophages in tissues.

• Lymphocytes: B and T cells, key to adaptive immunity.

Hemostasis

1. Vascular spasm

2. Platelet plug formation

3. Coagulation (blood clotting)

Additional info: Blood is covered in Ch. 17.

Heart

Cardiac Anatomy and Physiology

• Ischemia: Reduced blood flow to tissues.

• Myocardial infarction: Heart attack; death of cardiac muscle due to ischemia.

• Pacemaker cells: Initiate and regulate heartbeat (SA node).

• Systole: Contraction phase; Diastole: Relaxation phase.

• Stroke volume (SV): Volume of blood pumped per beat.

• Cardiac output (CO): $CO = SV \times HR$

• Preload: Degree of stretch of cardiac muscle before contraction.

• Afterload: Resistance the heart must overcome to eject blood.

Heart Structure and Blood Flow

• Four chambers: Right atrium, right ventricle, left atrium, left ventricle. Atria are superior chambers.

• Blood flow: Superior/inferior vena cava → right atrium → right ventricle → pulmonary artery → lungs → pulmonary vein → left atrium → left ventricle → aorta.

Heart Valves and Circulation

• AV valves: Separate atria and ventricles (tricuspid, bicuspid/mitral).

• Semilunar valves: Separate ventricles from arteries (pulmonary, aortic).

• Coronary circulation: Supplies blood to heart muscle itself.

Electrocardiogram (ECG/EKG)

• P wave: Atrial depolarization.

• QRS complex: Ventricular depolarization.

• T wave: Ventricular repolarization.

Additional info: Heart is covered in Ch. 18.

Blood Vessels

Vessel Structure and Function

• Arteries: Carry blood away from the heart; thick tunica media.

• Veins: Carry blood toward the heart; have valves, thinner walls.

• Capillaries: Site of exchange between blood and tissues.

Blood Pressure and Flow

• Systolic pressure: Pressure during ventricular contraction.

• Diastolic pressure: Pressure during ventricular relaxation.

• Pulse pressure: Difference between systolic and diastolic pressure.

• Mean arterial pressure (MAP): $MAP = \frac{1}{3} (\text{Systolic}) + \frac{2}{3} (\text{Diastolic})$

Types of Capillaries

Type	Structure	Location
Continuous	Uninterrupted lining	Muscle, skin, brain
Fenestrated	Pores in endothelium	Kidneys, intestines
Sinusoid	Large gaps	Liver, spleen

Shock

• Hypovolemic: Due to blood loss.

• Cardiogenic: Due to heart failure.

• Anaphylactic: Due to allergic reaction.

• Neurogenic: Due to nervous system injury.

• Obstructive: Due to physical obstruction.

• Septic: Due to infection.

Additional info: Blood vessels are covered in Ch. 19.

Respiratory System

Respiratory Anatomy and Physiology

• Inspiration/Expiration: Breathing in/out; involves diaphragm and intercostal muscles.

• Tidal volume (TV): Normal breath volume.

• Vital capacity (VC): Maximum exhaled after maximum inhalation.

• Compliance: Lung expandability.

• External respiration: Gas exchange in lungs.

• Internal respiration: Gas exchange in tissues.

Respiratory Histology

• Goblet cells: Secrete mucus.

• Cilia: Move mucus and trapped particles out of airways.

• Type I alveolar cells: Form alveolar wall for gas exchange.

• Type II alveolar cells: Secrete surfactant to reduce surface tension.

• Alveolar macrophages: Phagocytize debris and pathogens.

Additional info: Respiratory system is covered in Ch. 22.

Lymphatic System and Immunity

Lymphatic Structures and Functions

• Lymph: Fluid transported by lymphatic vessels.

• Lymph nodes: Filter lymph and house immune cells.

• Primary lymphatic structures: Bone marrow, thymus.

• Secondary lymphatic structures: Lymph nodes, spleen, tonsils.

Immunity

• Innate immunity: Non-specific, immediate defense (e.g., skin, phagocytes).

• Adaptive immunity: Specific, slower response (B and T lymphocytes).

• Antigen: Substance that triggers immune response.

• Antibody: Protein produced by B cells to neutralize antigens.

• Opsonization: Marking pathogens for phagocytosis.

• Clonal expansion: Rapid multiplication of lymphocytes after activation.

• Primary/secondary immune response: First/second exposure to antigen.

• IgG, IgA, IgM, IgE, IgD: Classes of antibodies with different roles.

Additional info: Lymphatic and immune systems are covered in Ch. 20-21.

Digestive System

Digestive Anatomy and Physiology

• Alimentary canal: Continuous tube from mouth to anus.

• Lumen: Inner space of the digestive tract.

• Mechanical digestion: Physical breakdown of food.

• Chemical digestion: Enzymatic breakdown of macromolecules.

• Absorption: Movement of nutrients into blood/lymph.

• Peristalsis: Wave-like muscle contractions moving food.

• Accessory organs: Liver, pancreas, gallbladder, salivary glands.

Digestive Histology

• Mucosa: Innermost layer; epithelium, lamina propria, muscularis mucosae.

• Submucosa: Connective tissue with blood vessels, nerves.

• Muscularis externa: Smooth muscle for peristalsis.

• Serosa: Outermost layer.

Digestive Enzymes and Hormones

• Amylase: Digests starch.

• Lipase: Digests fats.

• Pepsin: Digests proteins in stomach.

• Intrinsic factor: Needed for vitamin B12 absorption.

• CCK, Secretin: Regulate pancreatic and bile secretions.

Additional info: Digestive system is covered in Ch. 23.

Metabolism

Metabolic Pathways and Energy Balance

• Anabolism: Building complex molecules from simpler ones.

• Catabolism: Breaking down molecules for energy.

• Glycolysis: Glucose breakdown to pyruvate; produces ATP.

• Krebs Cycle: Produces NADH, FADH2, and ATP.

• Electron Transport Chain: Generates most ATP via oxidative phosphorylation.

• ATP: Main energy currency of the cell.

Key Equations

• ATP hydrolysis: $ATP + H_2O \rightarrow ADP + P_i + \text{energy}$

• NAD reduction: $NAD^+ + 2H \rightarrow NADH + H^+$

• FAD reduction: $FAD + 2H \rightarrow FADH_2$

Additional info: Metabolism is covered in Ch. 24.

Urinary System

Renal Anatomy and Physiology

• Nephron: Functional unit of the kidney; filters blood, forms urine.

• Glomerulus: Capillary network for filtration.

• Bowman's capsule: Surrounds glomerulus; collects filtrate.

• Proximal/distal convoluted tubule: Reabsorption and secretion.

• Loop of Henle: Concentrates urine.

• Collecting duct: Final urine concentration.

Hormonal Regulation

• ADH: Increases water reabsorption.

• Aldosterone: Increases Na+ reabsorption.

• ANP: Decreases blood volume/pressure.

• Renin-angiotensin-aldosterone system (RAAS): Regulates blood pressure and fluid balance.

Additional info: Urinary system is covered in Ch. 25.

Fluids and Electrolytes

Fluid Compartments and Balance

• Intracellular fluid (ICF): Fluid within cells.

• Extracellular fluid (ECF): Fluid outside cells (plasma, interstitial fluid).

• Electrolytes: Ions that help maintain fluid balance (Na+, K+, Ca2+, Cl-, HCO3-).

• Acidosis/Alkalosis: Imbalance in blood pH.

Water Balance

• Water gain: Drinking, food, metabolic water.

• Water loss: Urine, sweat, feces, respiration.

• Dehydration: Excessive water loss.

• Water intoxication: Excessive water intake diluting electrolytes.

Additional info: Fluids and electrolytes are covered in Ch. 26.

Reproductive System

Male and Female Reproductive Anatomy

• Spermatogenesis: Formation of sperm in testes.

• Oogenesis: Formation of ova in ovaries.

• Meiosis: Cell division producing gametes with half the chromosome number.

• Follicle development: Primordial → primary → secondary → Graafian follicle.

• Uterine cycle: Menstrual, proliferative, secretory phases.

• Hormonal regulation: FSH, LH, estrogen, progesterone.

Male Reproductive Structures

• Epididymis: Sperm maturation and storage.

• Vas deferens: Transports sperm.

• Seminal vesicles, prostate, bulbourethral glands: Contribute fluids to semen.

• Penis: Organ of copulation; contains erectile tissue.

Additional info: Reproductive system is covered in Ch. 27.