Renal System and Urinary Anatomy

Vocabulary flashcards covering key terms and definitions related to the renal system and urinary anatomy.

Renal System

The organ system that includes the kidneys, ureters, bladder, and urethra, functioning to filter blood and produce urine.

Nephron

The microscopic functional unit of the kidney that filters blood to produce urine; each kidney contains over 1 million nephrons.

Urinary Bladder

A hollow, muscular sac that stores urine before it is eliminated from the body.

Urethra

The thin-walled tube that carries urine from the bladder to the outside of the body; longer in males than in females.

Glomerulus

A ball of capillaries in the nephron where filtration of blood takes place.

Bowman's Capsule (Glomerular Capsule)

The cup-shaped end of the renal tubule that surrounds the glomerulus and receives the filtrate.

Filtration

The nonselective, passive process by which blood pressure in glomerular capillaries pushes fluids and small solutes out of the blood into the glomerular capsule.

Reabsorption

The process of diffusion and active transport of useful substances from the filtrate back into capillary blood.

Secretion

The active transport of additional substances from the blood into the renal tubule to become part of urine.

Antidiuretic Hormone (ADH)

A hormone produced by the hypothalamus that causes the kidneys to reabsorb more water, producing more concentrated urine.

Electrolytes

Substances that form ions in solution; essential for proper body function.

Renin

An enzyme produced by the kidneys in response to low blood pressure that triggers a series of reactions to constrict blood vessels.

Kidney Stones

Hard mineral or salt deposits that form in the kidneys, potentially causing severe pain.

Urinary Tract Infection (UTI)

A bacterial infection in the urinary tract that leads to frequent and painful urination.

Incontinence

An inability to hold urine in the bladder resulting in the involuntary loss of urine.

Adrenal Gland

An endocrine gland that sits atop the kidneys and produces hormones like aldosterone, which regulates salt and water balance.

Renal Capsule

A fibrous external covering that protects the kidneys.

Renal Cortex

The outer functional tissue of the kidney.

Renal Medulla

The inner functional tissue of the kidney, containing renal pyramids.

Renal Calyx

The cup-shaped area that collects urine from the base of the renal pyramids, draining into the renal pelvis.

Ureters

Tubes that transport urine from the kidneys to the urinary bladder.

Detrusor Muscle

The smooth muscle layer of the bladder that contracts to expel urine.

Trigone

The triangular area of the bladder wall formed by the ureter openings and the urethra.