Urinary system. Functions of Urinary System Removes waste Maintains acid-base balance of body Parts...
Transcript of Urinary system. Functions of Urinary System Removes waste Maintains acid-base balance of body Parts...
Urinary system
Functions of Urinary System
• Removes waste• Maintains acid-base
balance of body• Parts include:
– 2 KIDNEYS
– 2 URETERS
– BLADDER
– URETHRA
Kidneys
• 2 bean shaped organs• Protected by ribs and fat• Each kidney is found in mass of fatty tissue
(adipose capsule)• 2 main sections:
– Cortex: outer layer, contains most of the neurons that aid in production of urine
– Medulla: inner layer, contains most of tubes that carry urine from the nephrons through the kidneys
Nephrons• Microscopic filtering units• Over 1 million/kidney• Contains glomerulus
– Cluster of capillaries that filter waste
• Bowman’s capsule– Surround glomerulus picks
up filtered materials and passes it to the convoluted tubule
– Substances needed by the body are reabsorbed and returned to the capillaries
• At the end, most of the water, sugar, vitamins and salts have been reabsorbed
• Excess salts, water, wastes remain in the tubule and become urine
• Urine enters collecting ducts (tubes) in the medulla
• Collecting tubes empty into the renal pelvis (first section of the ureter)
Ureters• 2 muscular tubes 10-12
inches long
• One extends from the renal pelvis to the bladder
• Peristalsis: a wavelike motion of the involuntary muscle that moves urine through the ureter from the kidney to the bladder
Bladder
• Hollow muscular sac• Lining folds called rugae –
disappears as muscles of bladder allow it to expand and fill with urine
• 3 layers of visceral muscle• Urge to void occurs when
bladder contains 1 cup• Circular sphincter muscle
– Control bladder opening– Can’t be controlled by
infants
• FUNCTIONS:– Receives urine from
ureters
– Stores urine until eliminated from body
Urethra
• Tube carries urine from bladder to outside
• External opening called meatus
• Different in male/females– Females shorter– Opens in front of vagina or
passes through the penis– Male: carries both urine
from urinary system and semen from the reproductive system
• Liquid waste
• 95% water
• Excess useful products like sugar can be found, but usually indicates disease
• 1 ½ - 2 quarts produced daily
• 150 quarts filtered through kidneys
Urine
Key Terms
• Polyuria: excess urination• Oliguria: below normal urination• Anuria: absence of urination• Hematuria: blood in urine• Nocturia: urination at night• Dysuria: painful urination• Retention: inability to empty bladder• Incontinence: involuntary urination
Diseases
• Inflammation of the bladder
• More common in females due to shortness of urethra
Symptoms:
• Frequent urination
• Dysuria and burning
• Bladder spasm
• Hematuria
• ? Fever ?
Treatment:
• Antibiotics and increased fluid intake
Glomerulonephritis
• Inflammation of the glomerulus• Usually follows strep infection• Can be acute or chronic• Symptoms: hematuria, hypertension, edema,
fatigue, congestive heart failure, renal failure, death
• Treatment: treat symptoms– Low salt diet, high blood pressure medicine, dialysis,
transplant
Pyelonephritis
• Inflammation of kidney tissue and renal pelvis
• Usually caused by pus forming bacteria
• Symptoms: chills, fever, back pain, dysuria, hematuria and pyuria
• Treatment: antibiotics, increased fluid intake
Renal Calculi
• Kidney stone formed when salts in urine settle
• Small stones can be eliminated in urine• Large stones may become lodged• Symptoms: sudden pain, hematuria and
retention• Treatment: increase fluids, pain meds, strain
urine w/ gauze, lithotripsy, possible surgery
Renal Failure
• Kidneys stop functioning• Acute
– Caused by injury, poisoning, dehydration
– Prompt treatment leads to good prognosis
• Chronic– Progressive loss of kidney function caused by
glomerulonephritis, hypertension, toxins and endocrine disease.
– Waste accumulates and affects body systems
Uremia• Toxic condition where urinary waste is in
bloodstream• Caused from any condition that affects
proper function of kidneys• Symptoms: n/v, ammonia breath, anuria,
headache and confusion, coma/death• Treatment: restrictive diet, dialysis, transplant
Urethritis
• Inflammation of the urethra
• Caused by bacteria, viruses or chemicals
• Symptoms: painful urination, redness, itching at meatus, ?discharge
• Treatment: sitz baths or warm compresses, antibiotics, increased fluid intake
Identify parts of Urinary system
• Use handout to label all parts of the urinary system
• Use handout to trace flow of urine through the urinary system (name all parts as you go)