Anatomy of the Organ Systems – Foundations 1

Vocabulary flashcards summarizing key anatomical terms, tissue types, organ functions, circulations, and drug-related pathways discussed in the lecture.

Superior

An anatomical direction meaning toward the head or upper portion of the body.

Inferior

An anatomical direction meaning toward the feet or lower portion of the body.

Anterior (Ventral)

An anatomical direction referring to the front of the body.

Posterior (Dorsal)

An anatomical direction referring to the back of the body.

Medial

Closer to the midline of the body.

Lateral

Farther from the midline of the body.

Proximal

Closer to the point of attachment or origin (typically used for limbs).

Distal

Farther from the point of attachment or origin (typically used for limbs).

Superficial

Toward or at the body surface.

Deep

Away from the body surface; more internal.

Sagittal (Midline) Plane

An anatomical plane that divides the body into right and left portions.

Coronal (Frontal) Plane

An anatomical plane that divides the body into anterior and posterior portions.

Horizontal (Transverse) Plane

An anatomical plane that divides the body into superior and inferior portions.

Epithelial Tissue

Tissue composed of cells with a free surface that line cavities, ducts, tubes, and external surfaces.

Connective Tissue

Tissue that supports, binds, or separates other tissues and organs.

Muscle Tissue

Contractile tissue responsible for movement; includes skeletal, cardiac, and smooth types.

Nervous Tissue

Tissue specialized for signal transmission and processing.

Simple Epithelium

A single layer of epithelial cells.

Stratified Epithelium

Multiple layers of epithelial cells.

Cuboidal Cells

Epithelial cells roughly equal in height and width, cube-shaped.

Columnar Cells

Tall, rectangular epithelial cells lining many GI and respiratory surfaces.

Squamous Cells

Flat, thin epithelial cells; can be simple or stratified.

Loose Connective Tissue

Loose matrix of cells and collagen fibers; commonly underlies epithelium.

Dense Connective Tissue

Tissue with densely packed collagen and fewer cells than loose CT.

Skeletal Muscle

Voluntary, striated muscle attached to bones for body movement.

Cardiac Muscle

Striated, involuntary muscle found in the heart wall.

Smooth Muscle

Involuntary, non-striated muscle in walls of hollow organs and vessels.

Endothelium

Simple squamous epithelium lining all blood vessels.

Artery (Histology)

Blood vessel with thick smooth-muscle wall and smaller lumen, lined by endothelium.

Vein (Histology)

Blood vessel with thinner muscle wall, larger lumen, and thicker outer connective tissue.

Capillary

Smallest blood vessel (~1 RBC wide) consisting of endothelium plus a thin basement membrane.

Arteries (Function)

Carry blood away from the heart; systemic arteries carry oxygenated blood, pulmonary carry deoxygenated.

Veins (Function)

Return blood to the heart; systemic veins carry deoxygenated blood, pulmonary carry oxygenated.

Capillaries (Function)

Sites of exchange of gases, nutrients, and waste between blood and tissues.

Systemic Circulation

Circuit that delivers oxygenated blood from the left heart to the body and returns deoxygenated blood to the right heart.

Pulmonary Circulation

Circuit that carries deoxygenated blood from the right heart to the lungs and returns oxygenated blood to the left heart.

Portal Circulation

Venous system in which blood passes through two capillary beds (e.g., GI tract to liver) before reaching the heart.

Hepatic Portal Vein

Vein that carries nutrient-rich, deoxygenated blood from the GI tract to the liver.

Hepatic Veins

Veins that return blood from the liver to the inferior vena cava.

Pleura

Two-layered serous membrane (visceral and parietal) surrounding each lung and forming pleural cavities.

Pericardium

Two-layered serous membrane (visceral and parietal) enclosing the heart and forming the pericardial cavity.

Mediastinum

Central thoracic space between pleural cavities; contains heart, great vessels, trachea, esophagus, vagus nerves, sympathetic trunk, and more.

Stomach

Upper GI organ that mechanically and chemically digests food using acid and muscular contractions.

Duodenum

First part of the small intestine, divided into four parts; receives bile and pancreatic enzymes in second part.

Jejunum

Middle segment of the small intestine; major site of nutrient absorption via villi and microvilli.

Ileum

Distal segment of the small intestine; continues nutrient absorption and leads to large intestine.

Large Intestine

GI segment that reabsorbs water/electrolytes and eliminates waste; includes cecum, colon, sigmoid, and rectum.

Teniae Coli

Longitudinal smooth-muscle bands that contract and move feces along the large intestine.

Haustra

Pouch-like sacs of the large intestine created by teniae coli.

Epiploic Appendages

Small fatty projections on the surface of the large intestine.

Liver

Large RUQ organ that metabolizes toxins, stores glycogen, produces bile and plasma proteins.

Gall Bladder

Organ that stores and concentrates bile produced by the liver.

Pancreas

Gland that secretes digestive enzymes (exocrine) and hormones such as insulin and glucagon (endocrine).

Bile

Digestive fluid produced by the liver and stored in the gall bladder; aids fat digestion and drug excretion via bile route.

Autonomic Nervous System (ANS)

Involuntary motor system with two-neuron chains (preganglionic and postganglionic) controlling glands, smooth and cardiac muscle.

Sympathetic Nervous System (SANS)

“Fight or Flight” branch of ANS; preganglionic neurons in spinal cord, postganglionic neurons in sympathetic trunk or on aorta; uses norepinephrine at targets.

Parasympathetic Nervous System (PANS)

“Rest and Digest” branch of ANS; preganglionic neurons in CN III, VII, IX, X; postganglionic neurons on or near target organs; uses acetylcholine at targets.

Preganglionic Neuron

First neuron in autonomic pathway; cell body in CNS; releases acetylcholine at autonomic ganglion.

Postganglionic Neuron

Second neuron in autonomic pathway; cell body in ganglion; extends to target organ (NE in SANS, ACh in PANS).

Oral Drug Administration

Drug delivery route through mouth → GI lumen → epithelial layers → blood; subject to first-pass metabolism.

Intravenous Drug Administration

Direct drug delivery into a vein (e.g., median cubital) → systemic circulation, bypassing GI tract and first-pass effect.

First-Pass Effect

Initial metabolism of orally administered drugs in the liver via portal circulation before reaching systemic circulation.

Kidney

Organ that filters blood, forms urine, and serves as a major route for drug excretion.

Ureter

Muscular tube that carries urine from kidney to urinary bladder.

Urinary Bladder

Storage organ that holds urine prior to excretion through urethra.

Hepatopancreatic Ampulla

Union of common bile duct and pancreatic duct that releases bile and enzymes into the duodenum.

Microvilli

Microscopic projections on intestinal epithelial cells that increase surface area for absorption.

Basement Membrane

Thin layer of loose connective tissue anchoring epithelium (and endothelium) to underlying tissues.

Oral Cavity

Mouth region including hard palate, soft palate, tongue, and leading to pharynx; entry point for oral drugs.