Learn & Review: Comprehensive ATI TEAS 7 Science Anatomy and Physiology Study Guide With Practice Questions

ATIT's Version 7 Science Portion: Human Anatomy and Physiology Summary

This summary covers key aspects of the human anatomy and physiology relevant to the ATIT's Version 7 exam, including the respiratory, circulatory, nervous, digestive, endocrine, integumentary, skeletal, urinary, and immune systems, as well as muscle tissue and anatomical terminology.

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I. Respiratory System

• Air Pathway:
  • Nasal Cavity: Warms, humidifies, and filters air (nasal hairs, cilia).
  • Pharynx: Crossroads for air and food.
  • Larynx (Voice Box): Air passes through before the trachea.
  • Trachea: Cylindrical tube supported by cartilage rings, splits into primary bronchi.
  • Bronchi (Primary, Secondary, Tertiary): Branching tubes leading to the lungs.
  • Bronchioles: Smaller airways.
  • Alveolar Ducts: Lead to alveolar sacs.
  • Alveolar Sacs: Grape-like clusters containing alveoli.
  • Alveoli: Tiny sacs where gas exchange occurs.
• Epiglottis: Prevents food from entering the trachea.
• Lungs: Two lobes; right lung has three lobes, left lung has two lobes and a cardiac notch for the heart.
• Zones of the Lungs:
  • Conducting Zone: Trachea, bronchi, terminal bronchioles. Facilitates air passage, warms, humidifies, and filters air. Also known as "anatomical dead space" as no gas exchange occurs here.
  • Respiratory Zone: Respiratory bronchioles, alveolar ducts, alveoli. Site of actual gas exchange.
• Gas Exchange: Oxygen enters the blood, carbon dioxide is removed in the alveoli.
• Mechanisms of Breathing:
  • Inspiration (Inhalation): Active process involving diaphragm contraction (flattens) and external intercostal muscle contraction (lifts rib cage), increasing thoracic cavity volume and creating negative pressure.
  • Expiration (Exhalation): Typically passive process involving relaxation of diaphragm and external intercostals, decreasing thoracic cavity volume and increasing pressure. Forced expiration is active.
• Ventilation and Perfusion:
  • Ventilation: Movement of air in and out of lungs.
  • Perfusion: Blood flow to alveolar capillaries.
  • Balance: Optimal gas exchange requires balanced ventilation and perfusion.
• Breathing Regulation: Autonomic control by the nervous system, regulated by blood pH levels. Increased CO2 leads to increased acidity, detected by sensors that signal the brain to increase breathing rate and depth.

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II. Circulatory System

• Blood Composition:
  • Plasma: Liquid portion (water, proteins, salts, lipids).
  • Cellular Components: Red blood cells (gas transport), white blood cells (immune defense), platelets (clotting).
  • Hemoglobin: Iron-rich protein in red blood cells responsible for oxygen transport and red color.
• Blood Functions: Transport (gases, nutrients, hormones), pH maintenance, temperature regulation, osmotic pressure regulation, homeostasis.
• Blood Vessels:
  • Arteries: Carry blood away from the heart (usually oxygenated, except pulmonary arteries).
  • Veins: Carry blood back to the heart (usually deoxygenated, except pulmonary veins).
  • Capillaries: Tiny vessels where exchange of gases, nutrients, and waste occurs.
• Pulmonary Circulation: Exception where pulmonary arteries carry deoxygenated blood and pulmonary veins carry oxygenated blood.
• Heart Structure:
  • Chambers: Four chambers: Right atrium, right ventricle, left atrium, left ventricle.
  • Valves: One-way doors preventing backflow (tricuspid, pulmonary, mitral/bicuspid, aortic).
  • Blood Flow Through the Heart:
    1. Deoxygenated blood from body enters Right Atrium via vena cava (superior/inferior).
    2. Right Atrium contracts, pushing blood through Tricuspid Valve into Right Ventricle.
    3. Right Ventricle contracts, pushing blood through Pulmonary Valve into Pulmonary Artery.
    4. Pulmonary Artery carries blood to Lungs for oxygenation and CO2 removal.
    5. Oxygenated blood returns via Pulmonary Veins into Left Atrium.
    6. Left Atrium contracts, pushing blood through Mitral (Bicuspid) Valve into Left Ventricle.
    7. Left Ventricle contracts forcefully, pushing blood through Aortic Valve into Aorta.
    8. Aorta distributes oxygenated blood to the body.
• Coronary Circulation: Heart muscle receives oxygen and nutrients via coronary arteries branching from the aorta. Deoxygenated blood returns via coronary veins to the coronary sinus, then to the right atrium.
• Septal Defects: Abnormal openings in the septum dividing the heart chambers (atrial or ventricular septal defects), leading to mixing of oxygenated and deoxygenated blood.
• Electrical Conduction System:
  • Sinoatrial (SA) Node: Primary pacemaker in the right atrium (60-100 bpm). Initiates electrical impulse.
  • Bachmann's Bundle: Transmits signals from SA node to the left atrium.
  • Internodal Pathways: Anterior, middle, posterior pathways conduct signals through the atria.
  • Atrioventricular (AV) Node: Secondary pacemaker (40-60 bpm). Delays signal to allow atrial contraction before ventricular contraction.
  • Bundle of His: Transmits signals from AV node into the interventricular septum.
  • Bundle Branches (Right and Left): Transmit signals to respective ventricles.
  • Purkinje Fibers: Distribute signals to ventricular myocytes, initiating ventricular contraction (20-40 bpm).
  • Mnemonic: Strong Arteries Benefit Bodies Performance (SA node, AV node, Bundle Branches, Purkinje fibers).
• ECG (Electrocardiogram):
  • Isoelectric Line: Baseline representing no net electrical activity.
  • P Wave: Atrial depolarization (atrial contraction).
  • QRS Complex: Ventricular depolarization (ventricular contraction). Atrial repolarization occurs concurrently but is masked.
  • T Wave: Ventricular repolarization (ventricular relaxation).
• Blood Pressure:
  • Systolic Pressure: Top number; pressure during heart contraction (pumping blood out).
  • Diastolic Pressure: Bottom number; pressure when the heart is relaxed between beats.
  • Normal Range: Typically around 120/80 mmHg.

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III. Nervous System

• Divisions:
  • Central Nervous System (CNS): Brain and spinal cord. Command center.
  • Peripheral Nervous System (PNS): Nerves throughout the body. Gathers sensory info and relays motor commands.
• Brain Regions:
  • Hindbrain:
    • Medulla Oblongata: Regulates vital functions (breathing, heart rate, blood pressure). (Mnemonic: Medulla Manages)
    • Pons: Supports vital functions, coordinates communication between forebrain and cerebellum. (Mnemonic: Pons Passes)
    • Cerebellum: Balance and coordination of movements. (Mnemonic: Cerebellum Coordinates)
  • Midbrain: Alertness, sleep-wake cycle, motor activities, auditory and visual reflexes. (Mnemonic: MID Controls - Movement, Involvement in sleep-wake, Detection of reflexes)
  • Forebrain:
    • Cerebrum: Largest part, divided into two hemispheres. Houses cerebral cortex (outer layer of gray matter).
      • Cerebral Cortex: Site of higher-level processing, consciousness, sensory integration, and motor control.
      • Gray Matter: Neuron cell bodies, dendrites, unmyelinated axons; where information is processed.
      • White Matter: Myelinated axons; act as highways for rapid signal transmission.
      • Primary Motor Cortex (Frontal Lobe): Initiates voluntary movements.
      • Sensory Cortex (Parietal Lobe): Processes sensory information.
      • Association Areas: Integrate information, enhance functions of primary cortices (e.g., planning complex movements, interpreting sensory data).
      • Limbic System: Involved in memory, emotions, and behavior (eating, reproduction, fight-or-flight).
      • Frontal Lobe (Prefrontal Cortex): Highest level of cognitive function (planning, judgment, reasoning, behavior appropriateness).
      • Occipital Lobe: Visual processing.
      • Temporal Lobe: Auditory processing, long-term memory formation, speech comprehension (Wernicke's area), emotion and language processing.
• PNS Functional Divisions:
  • Somatic Nervous System: Controls skeletal muscles (voluntary and reflexes).
  • Autonomic Nervous System (ANS): Regulates internal environment (gastrointestinal, excretory, endocrine systems, smooth and cardiac muscle). Governs autonomic reflexes.
    • Sympathetic Nervous System: "Fight or flight" response (increases heart rate, respiratory rate; decreases digestion).
    • Parasympathetic Nervous System: "Rest and digest" response (slows heart rate, promotes digestion).
• Nervous Tissue Cells:
  • Neurons: Transmit electrical and chemical signals.
    • Cell Body: Contains organelles and nucleus.
    • Dendrites: Receive signals.
    • Axon: Carries signals away from the cell body.
    • Axon Terminal: Connects to other neurons at the synapse.
  • Glial Cells: Support and protect neurons. Include cells that produce myelin sheath, maintain chemical balance, support the blood-brain barrier, and produce cerebrospinal fluid.
• Neuron Input/Output:
  • Afferent (Sensory) Neurons: Carry signals towards the CNS. (Mnemonic: Afferent Arrives/ Admits)
  • Efferent (Motor) Neurons: Carry signals away from the CNS to muscles/glands. (Mnemonic: Efferent Exits)

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IV. Digestive System

• Four Main Functions: Ingestion, Digestion, Absorption, Elimination.
• Ingestion: Intake of food.
• Digestion: Breakdown of large biomolecules into building blocks (mechanical and chemical).
  • Mouth: Mechanical digestion (teeth), chemical digestion (salivary amylase breaks down carbohydrates). Saliva lubricates food, neutralizes acidity, and forms a bolus.
  • Esophagus: Muscular tube that transports the bolus to the stomach via peristalsis.
  • Epiglottis: Flap that covers the trachea during swallowing to prevent choking.
  • Stomach: Highly acidic environment (gastric juices: HCl, pepsin) for chemical digestion of proteins. Mechanical digestion through churning. Forms chyme (semi-liquid mixture).
    • Lower Esophageal Sphincter: Prevents reflux from stomach to esophagus.
    • Pyloric Sphincter: Controls passage of chyme into the small intestine.
  • Small Intestine: Primary site for digestion completion and nutrient absorption.
    • Duodenum: Chemical digestion (enzymes from pancreas, bile from liver), absorbs iron and minerals.
    • Jejunum: Primary site for nutrient absorption (carbohydrates, proteins) via villi.
    • Ileum: Absorbs vitamin B12, bile salts, and remaining digested products.
  • Accessory Organs:
    • Liver: Produces bile (emulsifies fats), metabolizes carbohydrates and proteins.
    • Gallbladder: Stores and releases bile.
    • Pancreas: Produces pancreatic juices (digestive enzymes), neutralizes acidic chyme, produces insulin and glucagon.
• Absorption: Nutrients are taken up by the body.
• Elimination: Expulsion of undigested waste.
  • Large Intestine: Absorbs water and salts, solidifies waste into stool.
    • Ascending Colon: Absorbs water and salt.
    • Transverse Colon: Storage, further water/salt absorption.
    • Descending Colon: Moves solid waste towards the rectum.
  • Rectum: Stores feces.
  • Anus: Expulsion of feces.
• Key Hormones:
  • Gastrin: Stimulates gastric secretion (pepsinogen, HCl).
  • Cholecystokinin (CCK): Stimulates gallbladder contraction (bile release) and pancreatic enzyme secretion.
  • Secretin: Regulates duodenal pH by inhibiting gastric acid and stimulating pancreatic bicarbonate production.
  • Insulin: Lowers blood glucose by facilitating uptake and storage.
  • Glucagon: Raises blood glucose by stimulating glycogen breakdown in the liver.
• Key Enzymes: Salivary amylase (carbohydrates), Pepsin (proteins), Bile (emulsifies fats).

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V. Endocrine System

• Function: Regulates body processes through hormones.
• Major Glands:
  • Brain: Hypothalamus, Pituitary Gland (anterior and posterior), Pineal Gland.
  • Neck: Thyroid Gland, Parathyroid Glands.
  • Chest: Thymus Gland.
  • Abdomen: Adrenal Glands (medulla and cortex), Pancreas.
  • Reproductive Organs: Gonads (Ovaries in females, Testes in males).
• Endocrine vs. Exocrine:
  • Endocrine: Release hormones directly into the bloodstream (ductless). (Mnemonic: Enter)
  • Exocrine: Use ducts to secrete substances onto body surfaces or cavities (e.g., sweat glands, mammary glands). (Mnemonic: Exit)
• Hormone Types: Amino acid-derived, polypeptide, lipid-derived (steroids).
• Key Hormones and Functions:
  • Hypothalamus: Produces releasing and inhibiting hormones for the pituitary.
  • Posterior Pituitary: Stores and releases hormones from the hypothalamus.
    • Oxytocin: Uterine contractions, milk letdown. (Mnemonic: Obstetrics)
    • Antidiuretic Hormone (ADH): Promotes water reabsorption by kidneys. (Mnemonic: Antidiuretic - Don't Have to pee)
  • Anterior Pituitary: Produces its own hormones.
    • Growth Hormone (GH): Promotes growth. (Mnemonic: Grow High)
    • Prolactin (PRL): Stimulates milk production. (Mnemonic: Produce Real Lactation)
    • Thyroid-Stimulating Hormone (TSH): Stimulates thyroid hormone release. (Mnemonic: Thyroid Secretion Helper)
    • Follicle-Stimulating Hormone (FSH): Stimulates ova and sperm production. (Mnemonic: Follicle Selection Hormone)
    • Luteinizing Hormone (LH): Triggers ovulation (females) and androgen production (males). (Mnemonic: Luteal Phase Hormone)
    • Adrenocorticotropic Hormone (ACTH): Stimulates adrenal cortex. (Mnemonic: Adrenal Cortex Triggering Hormone)
  • Pineal Gland: Melatonin (regulates circadian rhythm).
  • Thyroid Gland: T3 and T4 (metabolic rate), Calcitonin (lowers blood calcium). (Mnemonic: Thyroid Turns up metabolism; Calcitonin Down)
  • Parathyroid Glands: Parathyroid Hormone (PTH) (raises blood calcium). (Mnemonic: Parathyroid Pushes Up calcium)
  • Thymus Gland: Thymosin (stimulates T-cell production). (Mnemonic: Thymus Stimulates Immunity)
  • Adrenal Glands:
    • Medulla: Epinephrine, Norepinephrine (fight-or-flight). (Mnemonic: Epinephrine - No Rush)
    • Cortex: Glucocorticoids (Cortisol - stress, inflammation), Mineralocorticoids (Aldosterone - electrolyte balance, sodium reabsorption). (Mnemonic: Cortisol Controls Stress; Aldo Stores Na)
  • Pancreas: Insulin (lowers blood glucose), Glucagon (raises blood glucose). (Mnemonic: Insulin Puts Sugar In; Glucagon Raises Glucose)
  • Gonads:
    • Ovaries: Estrogen (uterine lining, female secondary characteristics), Progesterone (maintains uterine lining, fetal development).
    • Testes: Androgens (Testosterone - sperm production, male secondary characteristics).

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VI. Integumentary System (Skin)

• Functions: Homeostasis (temperature, fluid balance), protection (physical barrier, pathogen defense), Vitamin D synthesis, sensory perception.
• Layers of the Epidermis (Outer to Inner):
  • Stratum Corneum: Outermost layer, dead, hardened, keratinized cells (cornified cells).
  • Stratum Lucidum: Thickest skin areas (palms, soles), transparent, cornified cells.
  • Stratum Granulosum: Keratinocytes flatten, accumulate granules (water protection).
  • Stratum Spinosum: Keratinocytes, Langerhans cells (immune function).
  • Stratum Basale: Deepest layer, single layer of basal cells undergoing mitosis, melanocytes (produce melanin), Merkel cells (touch). (Mnemonic: Come Let's Get Sun Burned)
• Dermis: Connective tissue layer containing blood vessels, nerves, sweat glands, hair follicles. Composed of papillary (loose connective tissue) and reticular (dense connective tissue) layers. Contains collagen (strength) and elastin (elasticity).
• Hypodermis (Subcutaneous Tissue): Connective layer beneath the dermis, primarily adipose tissue (fat) for insulation.
• Accessory Structures:
  • Sweat Glands (Sudoriferous): Cool body through perspiration.
  • Sebaceous Glands: Produce oil (sebum) to waterproof and lubricate skin/hair.
  • Hair Follicles: Produce hair.
  • Nails: Protect fingertips/toes, originate from epidermis.
• Skin Conditions:
  • Skin Cancer: Uncontrolled cell division (basal cell carcinoma, squamous cell carcinoma, melanoma). Caused by UV radiation damage.
  • Burns: Classified by depth (first, second, third, fourth degree). Third and fourth-degree burns can cause less pain due to nerve damage. Impaired function, risk of infection.
  • Scars: Formed during deep wound healing in the dermis; fibroblasts produce collagen that doesn't align properly.

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VII. Urinary System

• Functions: Maintain osmotic pressure (water/solute balance), eliminate metabolic waste (CO2, nitrogenous waste).
• Organs: Kidneys, Ureters, Bladder, Urethra.
• Kidneys: Bean-shaped organs that filter blood and produce urine. Contain ~1 million nephrons (functional units).
• Nephron Function:
  • Glomerulus: Cluster of capillaries where filtration begins.
  • Bowman's Capsule: Encases the glomerulus; collects filtrate.
  • Filtration: Blood pressure forces fluid from glomerulus into Bowman's capsule. Filtrate contains water, glucose, amino acids, salts, ions, urea, vitamins, medications.
  • Reabsorption: Useful substances move from filtrate back into the blood.
  • Secretion: Substances move from blood into the renal tubule to be excreted.
  • Processing Journey:
    • Proximal Convoluted Tubule: Reabsorbs salt, water, glucose, amino acids, bicarb. Secretes hydrogen ions, ammonium. Crucial for pH regulation.
    • Loop of Henle:
      • Descending Limb: Permeable to water (reabsorbed); filtrate becomes more concentrated.
      • Ascending Limb: Permeable to salt (actively transported out); filtrate becomes more dilute.
    • Distal Convoluted Tubule: Reabsorbs salts, water, bicarbonate. Secretes hydrogen ions, potassium, ammonium. Further pH regulation.
    • Collecting Duct: Final urine concentration regulated by hormones (ADH). Urea reabsorption occurs. Transforms filtrate into urine.
• Urine Expulsion: Kidneys -> Ureters -> Bladder (storage) -> Urethra (excretion).

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VIII. Immune System

• Function: Defend against pathogens (viruses, bacteria, fungi, parasites).
• Lines of Defense:
  • First Line (External Defenses): Non-specific barriers.
    • Skin: Physical barrier.
    • Mucous Membranes: Trap pathogens.
  • Second Line (Internal Non-specific Defenses):
    • Inflammatory Response: Histamine release causes vasodilation and increased permeability, allowing white blood cells (macrophages) to reach the site.
    • Complement System: Enhances immune response, aids in pathogen elimination.
  • Third Line (Specific/Adaptive Immunity): Targets specific antigens.
    • Cell-Mediated Immunity: Involves Cytotoxic T cells that destroy infected cells by inducing apoptosis. Activated by antigens presented on infected cells or by macrophages. Helper T cells assist in activating cytotoxic T cells and B cells.
    • Humoral Immunity: Involves B cells that produce Antibodies.
      • Antibodies (Immunoglobulins - IgG, IgA, IgM, IgE, IgD): Bind to antigens, neutralize pathogens, mark for destruction by macrophages, activate complement.
      • B cell activation: Can be T-cell dependent or independent (direct antigen binding).
• Memory Cells: Memory B and T cells retain memory of encountered antigens for faster future responses.
• Types of Immunity:
  • Active Immunity: Body produces its own antibodies (natural exposure or vaccination). Long-lasting.
  • Passive Immunity: Antibodies are received from an external source (mother to baby, antibody therapies). Immediate but temporary.

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IX. Skeletal System

• Functions: Support, protection of organs, mineral reservoir, blood cell production (hematopoiesis), movement (with muscles).
• Bone Count: Adults typically have 206 bones.
• Divisions:
  • Axial Skeleton: Skull, ear ossicles, hyoid bone, vertebral column, rib cage. Forms the central axis.
  • Appendicular Skeleton: Arms, shoulder girdle, legs, pelvic girdle.
• Bone Classifications (Shape):
  • Long Bones: Longer than wide, cylindrical (e.g., femur, humerus, phalanges). Primarily involved in movement.
  • Short Bones: Cube-shaped, roughly equal length and width (e.g., carpals, tarsals). Provide stability.
  • Sesamoid Bones: Small, round, embedded in tendons (e.g., patella). Handle pressure.
  • Flat Bones: Thin, curved (e.g., cranial bones, scapulae). Provide structure and protection.
  • Irregular Bones: Complex shapes that don't fit other categories (e.g., vertebrae).
• Bone Tissue:
  • Compact Bone: Outer layer, hard and durable.
  • Spongy Bone (Cancellous/Trabecular): Inner layer, honeycomb-like structure containing bone marrow.
• Bone Marrow:
  • Yellow Marrow: Rich in fat, long-term energy storage.
  • Red Marrow: Site of hematopoiesis (production of red blood cells, white blood cells, platelets).
• Bone Cells:
  • Osteoblasts: Bone builders, create new bone matrix.
  • Osteocytes: Mature bone cells, maintain bone tissue.
  • Osteoclasts: Bone resorbing cells, break down bone tissue.
• Bone Remodeling: Continuous process of old bone removal and new bone formation, regulated by hormones. Involves resting, resorption, reversal, formation, and mineralization phases.
• Fractures: Breaks in bones.
  • Closed (Simple): Bone does not penetrate skin.
  • Open (Compound): Bone penetrates skin, high infection risk.
  • Comminuted: Bone shatters into three or more pieces.
  • Impacted (Buckle): Bone ends driven into each other.
  • Greenstick: Bone bends or cracks but doesn't break all the way through (common in children).
• Bone Healing: Involves hematoma formation, callus formation (internal cartilage, external cartilage/bone), osteoblast activity for repair, and mineralization.

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X. Muscle Tissue

• Types of Muscle Tissue:
  • Cardiac Muscle: Found in the heart. Branched, striated, single nucleus, involuntary control. Connected by intercalated discs for coordinated contraction.
  • Smooth Muscle: Found in walls of organs (digestive tract, blood vessels), iris. Non-striated, spindle-shaped, single nucleus, involuntary control.
  • Skeletal Muscle: Attached to bones and skin. Long, cylindrical fibers, striated, multiple nuclei, voluntary control.
• Muscle Fiber Characteristics: Extensibility (stretch), Elasticity (return to original shape), Excitability (respond to stimuli), Contractility (ability to shorten).
• Mechanism of Contraction (Sliding Filament Model):
  • Sarcomere: Basic contractile unit of muscle fiber.
  • Filaments: Actin (thin filaments), Myosin (thick filaments).
  • Process: Myosin heads bind to actin, forming cross-bridges. ATP hydrolysis energizes myosin heads. Power stroke pulls actin filaments towards the center of the sarcomere, causing shortening. ATP binding detaches myosin heads.
  • Rigor Mortis: Muscle rigidity after death due to lack of ATP to detach myosin heads.

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XI. Reproductive System

• Function: Facilitate mating, combination of genetic material, and reproduction.
• Components: Gonads (testes, ovaries), hormones, gametes (sperm, eggs), glands, ducts, external genitalia.
• Gametes: Haploid cells (sperm, ova) produced by meiosis.
• Fertilization: Fusion of sperm and egg to form a zygote.
• Male Reproductive System:
  • Gonads: Testes (produce testosterone, sperm).
  • Scrotum: External pouch holding testes (cooler temperature for sperm development).
  • Spermatogenesis: Sperm production within seminiferous tubules of testes.
  • Sperm Pathway: Seminiferous tubules -> Rete testis -> Epididymis (storage/maturation) -> Vas deferens -> Ejaculatory duct -> Urethra -> Penis.
  • External Genitalia: Scrotum, Penis (copulatory organ).
  • Accessory Glands:
    • Seminal Vesicles: Secrete fluid (semen) that nourishes sperm and aids motility.
    • Prostate Gland: Secretions activate sperm.
    • Bulbourethral Glands: Produce mucus for lubrication.
• Female Reproductive System:
  • Gonads: Ovaries (produce ova, estrogen, progesterone).
  • Oogenesis: Maturation of egg cells (oocytes).
  • Ovarian Structures: Follicles (contain oocytes), antrum (fluid-filled cavity in mature follicle).
  • Ovulation: Release of oocyte from ovary.
  • Pathway: Ovary -> Fallopian tubes (fertilization typically occurs here) -> Uterus (womb; implantation and development) -> Cervical canal -> Vagina (copulatory organ, birth canal).
  • External Genitalia (Vulva): Mons pubis, Labia majora, Labia minora, Vestibule (urethral and vaginal orifices).
  • Hormonal Regulation: Hypothalamus-pituitary-gonadal axis controls reproductive functions.

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XII. Anatomical Terminology

• Regional Terms:
  • Head: Cephalic, Cranial, Facial, Frontal, Temporal, Orbital/Ocular, Optic, Buccal, Nasal, Oral, Mental.
  • Trunk/Limbs: Cervical (neck), Axillary (armpit), Brachial (arm), Antibrachial (forearm), Carpal (wrist), Palmar (palm), Pollex (thumb), Digital/Phalange (fingers/toes), Sternal (breastbone), Thoracic (chest), Mammary (breast), Abdominal (abdomen), Umbilical (navel), Coxa (hip), Femoral (thigh), Patellar (front of knee), Crural (shin), Pedal (foot), Tarsal (ankle), Dorsum (top of foot/back of hand), Hallux (great toe), Manual (hand), Pelvic (pelvis), Inguinal (groin), Pubic (pubis).
  • Posterior (Back): Occipital (base of skull), Acromial (shoulder), Scapular (shoulder blade), Vertebral (spinal column), Dorsal (back), Olecranal/Cubital (back of elbow), Lumbar (loin), Sacral (between hips), Coccygeal (tailbone), Gluteal (buttocks), Perineal (between anus and genitalia), Popliteal (back of knee), Sural (calf), Plantar (sole of foot), Calcaneal (heel).
• Planes:
  • Transverse Plane: Horizontal division into superior and inferior parts. Allows rotational movements.
  • Frontal (Coronal) Plane: Divides body into anterior and posterior parts. Allows side-to-side movements (abduction, adduction).
  • Sagittal Plane: Divides body into left and right sides. Allows forward and backward movements (flexion, extension).
• Directional Terms:
  • Anterior (Ventral): Front of the body.
  • Posterior (Dorsal): Back of the body.
  • Medial: Closer to the midline of the body.
  • Lateral: Further away from the midline of the body.
  • Superior (Cranial): Above another body part.
  • Inferior (Caudal): Below another body part.
  • Proximal: Closer to the point of attachment to the body.
  • Distal: Further away from the point of attachment to the body.