VESSELS & CIRCULATION
The largest artery in the body, carrying blood out of the left ventricle
The aorta
Gas exchange happens only in these tiny air sacs.
The alveoli
The functional (filtering) unit of the kidney.
The nephron
The muscular waves that push food along the tract.
Peristalsis
Sperm are made here, in the testes.
The seminiferous tubules
The one artery that carries oxygen-poor blood.
The pulmonary artery
The bean-shaped structure that filters lymph and swells during infection.
A lymph node
The four organs of the urinary system, in order of urine flow.
Kidneys → ureters → bladder → urethra
The organ that makes bile, and the one that stores it.
Liver makes it; gallbladder stores it
Fertilization normally happens in this region of the fallopian tube.
The ampulla
The three branches of the aortic arch, in order.
Brachiocephalic trunk, left common carotid, left subclavian
The main stimulus that drives breathing (not low oxygen).
Rising carbon dioxide (CO₂)
The three steps of urine formation, in order.
Filtration, reabsorption, secretion
About this percentage of absorption happens in the small intestine.
90%
The gland that adds fructose to energize sperm.
The seminal vesicles
The ring of arteries at the base of the brain that reroutes blood if one feeder is blocked.
The Circle of Willis
The largest lymphatic organ, in the left upper quadrant.
The spleen
The two things that should NOT normally enter the filtrate.
Blood cells and proteins
The three structures that multiply the small intestine's surface area.
Circular folds, villi, and microvilli
Estrogen builds the uterine lining; this hormone maintains it.
Progesterone
The vein that carries gut blood to the liver before it returns to the heart.
The hepatic portal vein
The type of immunity that is specific and has memory — the basis of vaccines.
Adaptive (specific) immunity
The fascia that encloses the kidney and defines the perirenal space.
Gerota's (renal) fascia
The organ that is both exocrine (enzymes) and endocrine (insulin/glucagon).
The pancreas
After ovulation, the ruptured follicle becomes this progesterone-maker.
The corpus luteum