Human Anatomy & Physiology – Master Vocabulary

192 vocabulary flashcards covering essential terms across anatomical orientation, respiratory, cardiovascular, digestive, nervous, muscular, reproductive, integumentary, endocrine, urinary, immune, and skeletal systems to support TEAS A&P review.

Anatomical Position

Standard reference stance—body erect, facing forward, arms at sides, palms forward.

Coronal (Frontal) Plane

Vertical plane that divides the body into anterior (front) and posterior (back) portions.

Transverse (Horizontal) Plane

Plane that divides the body into superior (upper) and inferior (lower) portions.

Sagittal (Median) Plane

Vertical plane that divides the body into right and left portions.

Superior

Toward the head or upper part of a structure; above.

Inferior

Away from the head; toward the lower part; below.

Anterior (Ventral)

Toward the front of the body.

Posterior (Dorsal)

Toward the back of the body.

Medial

Toward the midline of the body.

Lateral

Away from the midline; toward the side.

Respiratory System

Organ system that exchanges oxygen and carbon dioxide between atmosphere and blood.

Ventilation

Mechanical movement of air into and out of the lungs.

Alveoli

Microscopic air sacs in the lungs where gas exchange occurs.

Surfactant

Lipoprotein secreted by type II alveolar cells that lowers surface tension in alveoli.

Diaphragm

Dome-shaped skeletal muscle that drives inspiration by increasing thoracic volume.

Tidal Volume

Amount of air inhaled or exhaled during a normal breath.

Residual Volume

Air remaining in the lungs after maximal exhalation.

Trachea

Windpipe; airway connecting larynx to primary bronchi.

Bronchioles

Small airway branches leading from bronchi to alveolar ducts.

Medulla Oblongata (Respiratory Center)

Brainstem region that monitors CO₂/pH and regulates breathing rate.

Pleura

Double-layered membrane surrounding the lungs; contains lubricating pleural fluid.

Diffusion (Gas Exchange)

Passive movement of gases across the alveolar–capillary membrane.

Asthma

Condition in which airway inflammation and narrowing impede airflow.

Pulmonary Artery

Vessel carrying deoxygenated blood from right ventricle to lungs.

Pulmonary Vein

Vessel carrying oxygenated blood from lungs to left atrium.

Cardiovascular System

Closed circulatory network that transports blood, nutrients, hormones, and wastes.

Pulmonary Circulation

Loop that carries deoxygenated blood from right ventricle to lungs and back to left atrium.

Systemic Circulation

Loop that carries oxygenated blood from left ventricle to body and back to right atrium.

Atrium

Upper heart chamber that receives returning blood.

Ventricle

Lower heart chamber that pumps blood out of the heart.

Systole

Phase of cardiac cycle when heart muscle contracts.

Diastole

Phase of cardiac cycle when heart muscle relaxes and fills with blood.

Sinoatrial (SA) Node

Heart’s natural pacemaker initiating electrical impulses.

Atrioventricular (AV) Node

Conductive node that delays impulse, allowing ventricles to fill.

Bundle of His

Conductive fibers transmitting impulses from AV node to ventricles.

Purkinje Fibers

Network delivering impulse to ventricular myocardium for contraction.

Hemoglobin

Iron-containing protein in red blood cells that binds and transports oxygen.

Plasma

Liquid component of blood carrying nutrients, hormones, and wastes.

Red Blood Cell (Erythrocyte)

Blood cell that transports oxygen via hemoglobin.

White Blood Cell (Leukocyte)

Immune cell that defends the body against pathogens.

Platelet

Cell fragment that initiates blood clotting.

Artery

Blood vessel with thick muscular walls that carries blood away from the heart.

Vein

Blood vessel with valves that returns blood to the heart.

Capillary

Microscopic vessel where exchange between blood and tissues occurs.

Blood Pressure

Force exerted by circulating blood on vessel walls.

Systolic Pressure

Peak arterial pressure during ventricular contraction.

Diastolic Pressure

Lowest arterial pressure during ventricular relaxation.

Electrocardiogram (ECG/EKG)

Recording of the heart’s electrical activity.

Coronary Arteries

Vessels supplying oxygenated blood to heart muscle.

Digestive System

System that ingests food, breaks it down, absorbs nutrients, and eliminates waste.

Peristalsis

Wave-like smooth-muscle contractions that move food through the GI tract.

Bolus

Chewed food mixed with saliva ready for swallowing.

Chyme

Semiliquid mixture of partially digested food in the stomach/small intestine.

Esophageal (Cardiac) Sphincter

Valve preventing gastric reflux into the esophagus.

Pyloric Sphincter

Valve controlling chyme passage from stomach to duodenum.

Duodenum

First section of the small intestine; receives bile and pancreatic juices.

Jejunum

Middle portion of small intestine; principal site of nutrient absorption.

Ileum

Terminal section of small intestine that absorbs vitamin B12 and bile salts.

Villi

Finger-like projections lining the small intestine that increase surface area.

Microvilli

Microscopic folds on villi cells that further increase absorptive area.

Bile

Emulsifying fluid produced by liver, stored in gallbladder, aiding fat digestion.

Gallbladder

Organ that stores and concentrates bile.

Pancreas (Digestive)

Gland that secretes digestive enzymes and bicarbonate into the duodenum.

Ghrelin

Stomach hormone that stimulates hunger.

Leptin

Adipose-derived hormone that promotes satiety.

Insulin

Pancreatic hormone that promotes cellular uptake of glucose.

Glucagon

Pancreatic hormone that raises blood glucose by stimulating glycogen breakdown.

Gastrin

Stomach hormone that stimulates acid and pepsinogen secretion.

Cholecystokinin (CCK)

Hormone that triggers bile release and pancreatic enzyme secretion.

Secretin

Hormone that stimulates pancreatic bicarbonate to neutralize chyme.

Nervous System

Network coordinating body activities via electrical and chemical signals.

Central Nervous System (CNS)

Brain and spinal cord.

Peripheral Nervous System (PNS)

All neural tissue outside the CNS.

Neuron

Functional nerve cell that transmits electrical impulses.

Synapse

Junction where a neuron communicates with another cell.

Sensory (Afferent) Neuron

Neuron carrying impulses from receptors to CNS.

Motor (Efferent) Neuron

Neuron carrying impulses from CNS to effectors.

Somatic Nervous System

PNS division controlling voluntary skeletal muscles.

Autonomic Nervous System

PNS division regulating involuntary functions.

Sympathetic Division

Branch of ANS mediating fight-or-flight responses.

Parasympathetic Division

Branch of ANS promoting rest-and-digest activities.

Myelin Sheath

Insulating lipid layer that speeds impulse conduction along an axon.

Action Potential

Rapid electrical signal traveling along a neuron’s membrane.

Cerebellum

Brain region coordinating balance and fine motor control.

Pons

Brainstem structure relaying signals between forebrain and cerebellum.

Medulla Oblongata (Brainstem)

Brainstem area controlling breathing, heart rate, and blood pressure.

Hypothalamus

Brain region linking nervous and endocrine systems; regulates homeostasis.

Thalamus

Brain relay station for sensory information.

Limbic System

Group of brain structures governing emotion and memory.

Skeletal Muscle

Striated voluntary muscle attached to bones for movement.

Cardiac Muscle

Striated involuntary muscle forming the heart wall.

Smooth Muscle

Non-striated involuntary muscle in walls of hollow organs.

Sarcomere

Contractile unit of a muscle fiber, between two Z discs.

Myofibril

Bundle of actin and myosin filaments within a muscle fiber.

Actin

Thin filament that interacts with myosin during contraction.

Myosin

Thick filament whose heads hydrolyze ATP to power contraction.

Tendon

Dense connective tissue connecting muscle to bone.

Sliding Filament Theory

Model describing actin and myosin sliding past each other to shorten sarcomere.

ATP (Muscle Contraction)

Energy molecule required for cross-bridge cycling and muscle relaxation.

Neuromuscular Junction

Synapse between a motor neuron and skeletal muscle fiber.