Urinary system pt 1

Urinary System

The system responsible for excreting waste, composed of kidneys and the urinary tract.

Kidney Functions

Includes filtering blood, regulating fluid and electrolyte balance, maintaining acid-base homeostasis, influencing blood pressure, releasing erythropoietin, detoxifying substances, and activating Vitamin D.

Ureters

Tubes through which urine exits the kidneys, located on the posterior body wall.

Urinary Bladder

The organ where urine is stored, located on the floor of the pelvic cavity.

Urethra

The duct that allows urine to exit the body from the urinary bladder.

Renal Capsule

A thin layer of dense irregular connective tissue covering each kidney.

Adipose Capsule

A fatty layer that protects the kidneys from physical trauma.

Renal Fascia

A layer of dense irregular connective tissue that anchors the kidneys to surrounding structures.

Hilum

An opening on the medial surface of the kidney for entry and exit of vessels and ureters.

Renal Cortex

The outer region of the kidney where most kidney blood vessels are located.

Renal Medulla

The inner region of the kidney.

Renal Columns

Extensions of the renal cortex that pass through the renal medulla.

Renal Pyramids

Cone-shaped structures in the renal medulla, separated by renal columns.

Renal Papilla

The tapered end of each renal pyramid.

Nephron

The functional unit of the kidney, responsible for filtering blood and forming urine.

Renal Corpuscle

The part of the nephron that filters blood, composed of the glomerulus and Bowman’s capsule.

Podocytes

Cells in the visceral layer of the glomerular capsule that create filtration slits.

Proximal Tubule (PCT)

Part of the nephron involved in reabsorption and secretion, featuring microvilli.

Nephron Loop (Loop of Henle)

Part of the nephron that reabsorbs substances; consists of descending and ascending limbs.

Distal Tubule (DCT)

Part of the nephron involved in reabsorption and secretion, with fewer microvilli.

Juxtaglomerular Apparatus (JGA)

Regulates blood pressure and glomerular filtration rate via renin release.

Collecting System

Series of ducts that transport modified filtrate to the papillary duct, where it becomes urine.

Cortical Nephrons

Nephrons with renal corpuscles in the outer cortex and short loops.

Juxtamedullary Nephrons

Nephrons located near the cortex-medulla boundary with long loops into the medulla.

Arterial Pathway to Kidneys

Sequence of arteries supplying kidneys: renal artery → segmental artery → interlobar artery → arcuate artery → interlobular artery.

Venous Pathway from Kidneys

Sequence of veins draining kidneys: interlobular veins → arcuate veins → interlobar vein → renal vein.

Glomerular Filtration

The process of filtering blood based on the size of substances.

Tubular Reabsorption

Process of reclaiming water and solutes from tubular fluid back into blood.

Tubular Secretion

Process of adding substances from blood to filtrate for electrolyte and acid-base balance.