Chapter 23, Lesson 7: Urine Storage and Elimination

Flashcards from Chapter 23, Lesson 7 of McGraw Hill Anatomy and Physiology, Tenth Edition, by Kenneth S. Saladin.

Ureters

Muscular tubes that extend from the kidney to the urinary bladder; about 25 cm long with a flap of mucosa to prevent backflow

Urinary bladder

A muscular sac located on the floor of the pelvic cavity, has layers of the detrusor, trigone, and rugae

Detrusor

Three layers of smooth muscle in the urinary bladder wall

Trigone

A smooth triangular area marked by openings of the two ureters and the urethra

Rugae

Conspicuous wrinkles in the empty bladder for more surface area and extension

Renal calculus (kidney stones)

Hard deposits of minerals that form in the renal pelvis; can be small and pass unnoticed or larger, causing painful blockages in the renal pelvis or ureter

Kidney stone causes

Caused by:

• Hypercalcemia

• Dehydration

• pH imbalances

• Frequent UTIs

• Enlarged prostate causing urine retention

Kidney stone treatments

Treated with:

• Stone-dissolving drugs

• Surgery

• Shock wave lithotripsy (pulverization with ultrasound)

Urethra

A tube that conveys urine out of the body; female urethras as 3 to 4 cm long and male urethras are 18 cm long

External urethral orifice

Female urethra; between the vaginal orifice and clitoris

Male urethra region

1. Prostatic urethra (2.5 cm): passes through prostate

2. Membranous urethra (0.5 cm): passes through muscular pelvic cavity floor

3. Spongy urethra (15 cm): passes through penis in corpus spongiosum

Internal urethral sphincter

Urethral sphincter only in males with a thickened collar of muscle around the neck of the bladder, nearby urethra

External urethral sphincter

Urethral sphincter in both sexes where the urethra passes through the pelvic floor

Cystitis

Infection of the urinary bladder; common in females due to short urethra and an be triggered by sexual intercourse

Pyelitis

Infection of the renal pelvis

Pyelonephritis

Infection that reaches the cortex and nephrons; can result from blood-borne bacteria

Micturition

The act of urinating following the filling of the bladder; controlled by pons with stretch receptor signals to either relax or contract the sphincter for voiding or retention

Renal insufficiency

A state in which the kidneys cannot maintain homeostasis due to extensive nephron destruction; kidneys can regenerate or hypertrophy to compensate

Hemodialysis

A procedure for artificially clearing wastes from the blood; it is cleaned by a machine with dialysis fluid