Human Anatomy & Physiology – Core Vocabulary

A comprehensive set of key vocabulary terms drawn from the lecture covering human anatomy, physiology, biochemistry, cell biology, tissues, organ systems, and foundational principles such as homeostasis and metabolism.

Anatomy

Scientific discipline that investigates body structures, often by dissection.

Physiology

Study of the functions and processes of living organisms.

Developmental Anatomy

Branch examining structural changes from conception to adulthood.

Embryology

Sub-field of developmental anatomy focusing on the first eight weeks after conception.

Cytology

Microscopic study of cell structure and function.

Histology

Microscopic study of tissues and the materials surrounding them.

Gross Anatomy

Study of structures visible without a microscope.

Systematic Anatomy

Approach that studies the body system by system.

Regional Anatomy

Approach that studies the body area by area.

Surface Anatomy

Examination of external structures as landmarks for deeper organs.

Chemical Level

Smallest level of organization; atoms interact to form molecules.

Cell Level

Basic structural and functional units—cells and their organelles.

Tissue Level

Groups of similar cells performing common functions.

Organ Level

Two or more tissue types working together as organs.

Organ System Level

Group of organs performing a common set of functions.

Homeostasis

Maintenance of a relatively constant internal environment.

Variable

Physical or chemical factor that can change and is regulated (e.g., temperature).

Set Point

Ideal normal value of a variable around which homeostasis is maintained.

Negative Feedback

Homeostatic mechanism that reduces or resists deviation from a set point.

Positive Feedback

Response that enhances or exaggerates the original stimulus.

Sagittal Plane

Vertical plane dividing the body into left and right portions.

Transverse (Horizontal) Plane

Plane that divides the body into superior and inferior parts.

Frontal (Coronal) Plane

Vertical plane dividing the body into anterior and posterior sections.

Thoracic Cavity

Body cavity enclosed by the rib cage above the diaphragm.

Mediastinum

Central compartment of the thoracic cavity housing heart, trachea, etc.

Serous Membrane

Double-layered membrane lining trunk cavities and covering organs.

Parietal Membrane

Serous layer lining the cavity wall.

Visceral Membrane

Serous layer covering an organ surface.

Pericardial Cavity

Serous cavity surrounding the heart.

Pleural Cavity

Serous cavity surrounding a lung.

Peritoneal Cavity

Serous cavity within the abdominopelvic cavity.

Element

Simplest type of matter with unique chemical properties.

Atom

Smallest particle of an element retaining its properties.

Proton

Positively charged subatomic particle in the nucleus.

Neutron

Neutral subatomic particle in the nucleus.

Electron

Negatively charged particle orbiting the nucleus.

Isotope

Atoms of the same element with different numbers of neutrons.

Ionic Bond

Chemical bond formed by transfer of electrons creating charged ions.

Covalent Bond

Bond formed by sharing electron pairs between atoms.

Hydrogen Bond

Weak attraction between a hydrogen atom and an electronegative atom.

Electrolyte

Ion in solution capable of conducting electricity.

Anabolism

Energy-using synthesis reactions building larger molecules.

Catabolism

Energy-releasing decomposition reactions breaking molecules apart.

Enzyme

Protein catalyst that speeds reactions by lowering activation energy.

pH Scale

Measurement of hydrogen-ion concentration from 0 (acidic) to 14 (alkaline).

Buffer

Substance that resists changes in pH when acids or bases are added.

Monosaccharide

Single sugar unit, e.g., glucose or fructose.

Disaccharide

Two monosaccharides joined (e.g., sucrose).

Polysaccharide

Long chain of monosaccharides (e.g., glycogen, starch).

Triglyceride

Lipid composed of glycerol plus three fatty acids; major fat storage.

Phospholipid

Lipid with two fatty acids and a phosphate group; forms cell membranes.

Hydrophilic

Water-loving; attracted to water (polar).

Hydrophobic

Water-fearing; repelled by water (non-polar).

Protein

Polymer of amino acids joined by peptide bonds.

Denaturation

Loss of protein shape (and function) due to heat or pH changes.

DNA

Double-stranded nucleic acid storing genetic information.

RNA

Single-stranded nucleic acid involved in protein synthesis.

ATP

Adenosine triphosphate; primary energy currency of the cell.

Plasma Membrane

Selectively permeable boundary of a cell.

Facilitated Diffusion

Passive transport using carrier proteins down a concentration gradient.

Active Transport

Energy-requiring movement of substances against a gradient via carriers.

Endocytosis

Bulk transport of material into a cell by vesicle formation.

Exocytosis

Vesicular release of material from a cell.

Cytoskeleton

Network of protein filaments (microtubules, microfilaments) supporting cell shape.

Mitochondrion

Organelle that produces ATP through aerobic respiration.

Transcription

Synthesis of RNA from a DNA template.

Translation

Assembly of a protein at a ribosome using mRNA codons.

Mitosis

Division of a nucleus into two genetically identical nuclei.

Apoptosis

Programmed cell death regulating cell numbers.

Epithelial Tissue

Sheet of cells covering surfaces and lining cavities.

Connective Tissue

Tissue with extensive extracellular matrix providing support and connection.

Muscle Tissue

Contractile tissue responsible for movement.

Nervous Tissue

Tissue capable of conducting electrical impulses.

Basement Membrane

Extracellular layer attaching epithelium to connective tissue.

Simple Epithelium

Single layer of epithelial cells.

Stratified Epithelium

Multiple layers of epithelial cells for protection.

Keratinized

Epithelium with dead, protein-filled surface cells (e.g., skin).

Endocrine Gland

Ductless gland releasing hormones into blood.

Exocrine Gland

Gland with ducts secreting onto surfaces or into cavities.

Cartilage

Supportive connective tissue with semi-rigid matrix and chondrocytes.

Spongy Bone

Porous bone tissue containing trabeculae; interior of bones.

Compact Bone

Dense bone tissue forming outer bone layers.

Neuron

Nerve cell specialized for signal conduction.

Action Potential

Rapid reversal of membrane potential propagating along an excitable cell.

Synapse

Junction where a neuron communicates with another cell.

Hormone

Chemical messenger secreted into blood to regulate distant cells.

Insulin

Pancreatic hormone that lowers blood glucose.

Glucagon

Pancreatic hormone that raises blood glucose.

Homeostatic Mechanism

Process that maintains internal stability (e.g., sweating, shivering).

Reflex Arc

Neuronal pathway mediating an automatic response to a stimulus.

Enamel

Hard crystalline covering of the tooth crown.

Peristalsis

Wave-like muscle contractions moving material through the digestive tract.

Alveolus (lung)

Microscopic air sac where gas exchange occurs.

Nephron

Functional unit of the kidney filtering blood and forming urine.

Glomerulus

Capillary knot where filtration of blood plasma begins in the nephron.

Spermatogenesis

Process of sperm cell production in testes.

Oogenesis

Formation and development of oocytes in ovaries.

Meiosis

Specialized cell division producing haploid gametes.

Zygote

Fertilized egg formed by union of sperm and oocyte.

Placenta

Organ that exchanges nutrients and wastes between mother and fetus.