HESI ANATOMY & PHYSIOLOGY URINARY SYSTEM Flashcards
Cortex
Outer portion of the kidney
Medulla
Inner portion of the kidney
Nephron
Microscopic structure in kidney that produces urine
Peritoneum
Membrane surrounding abdominal cavity
Retroperitoneal
Behind the peritoneum
Genitourinary system
consists of the kidneys, ureters, urinary bladder, and urethra.
vital to maintaining fluid, electrolyte and pH balance, activates vitamin D, helps to stimulate red blood cell development and removes toxins from the blood.
Kidneys
Paired organs located behind the peritoneal membrane (retroperitoneal)
Bean shaped
Outer layer of the kidney consists of a layer of fibrous connective tissue called the renal capsule.
Located in the low back area and extend just below the ribs. They are behind the abdominal membrane (retroperitoneal).
Inside of the kidney
divided into an outer cortical region (cortex) and an inner medulla. The medulla contains conical structures called renal pyramids.
The Nephron
functional unit of the kidney is a microscopic structure called the nephron
consists of a renal tubule and a renal corpuscle
renal corpuscle
is a spherical structure that consists of a capillary network called the glomerulus surrounded by a fibrous capsule called the glomerular capsule (Bowman’s capsule).
capillary network
fed by an afferent arteriole
Urine
flows from the collecting duct to the renal papilla, minor calyx, major calyx, renal pelvis, ureter, bladder and urethra.
3 processes of urine formation that all occur in the nephron.
Filtration occurs in the glomerulus and glomerular capsule. Substances move from higher to lower pressure and are sorted by size.
Tubular reabsorption
occurs in the proximal and distal convoluted tubules and collecting duct.
Aquaporin:
Transport protein located in the descending limb that transport water.
Ascending Limb:
Thick segment of the nephron loop.
thick segment of the ascending limb inhibits the passage of water by diffusion and contains a series of active transport proteins that selectively move substance
Descending Limb
Thin segment of the nephron loop.
contains a thin layer of epithelium that is more permeable to water than the thick portion of the ascending limb
Isotonic
A solution that is the same concentration as body fluid.
Hypertonic:
A solution that is more concentrated than body fluid.
Hypotonic
A solution that is less concentration than body fluid.
NKCC
Sodium, potassium, chloride, co-transporter protein that actively transports these substances out of the ascending limb.
The Nephron Loop: Consist of two segments
descending and ascending segment each with different characteristics.
Nephron loop assists
urine formation by transporting water and electrolytes in opposite directions (countercurrent mechanism), creating a hypertonic environment in the medulla
Ureters carry
urine from the kidney to the bladder
Ureters have
smooth muscle layer that is capable of producing peristaltic contractions that occur once every two to three minutes
Urinary bladder
hollow organ that resides in the pelvic cavity.
Male bladders contain
area of smooth muscle and elastic tissue called the internal urinary sphincte
Not present in female
function of this structure is to keep semen from entering the urinary bladder during intercourse
male urethra consists of three parts.
prostatic urethra exits the bladder and extends to the inferior prostate gland.
Micturition (urination)
a voluntary reflex that is under control of the parasympathetic nervous system.
