Question 1 In the nephron, filtrate that leaves the Bowman’s capsule then enters the ________. A. loop of Henle B. distal convoluted tubule C. proximal convoluted tubule D. collecting tubule E. glomerulus

Answer: C

Question 2 What would happen to the function of the nephron if the pH of the blood were decreased?

Answer Low pH means excess of H + ions in the blood. The kidney’s function is to remove those ions from the blood and put them into the filtrate in the nephrons, eventually expelling them from the body through urine.

Question 3 What is the purpose of the tubules/loop of Henle?

Answer Tubules and Loop of Henle are sites of excretion and reabsorption, through diffusion. They allow water, ions, urea, and waste to be filtered into filtrate that becomes urine. They also allow reabsorption of water and ions to maintain correct balance.

Micturition Micturition= urination, or voiding the bladder Begins with involuntary contractions of detrusor muscle of bladder wall

Micturition Increased volume of urine in bladder causes increased bladder pressure This triggers parasympathetic stimulation of involuntary contractions of detrusor muscles in bladder What is parasympathetic nervous system?

Micturition Parasympathetic reflex causes relaxation of internal urethral sphincter muscles- ring structure in bladder wall We can consciously control voluntary contraction of external urethral sphincter muscles- using skeletal muscle of pelvic floor Both muscles must relax for micturition

CNS must mature and grow sufficiently for conscious control of urination Infants and those with CNS injury can’t control Incontinence: involuntary micturition

Question Why do you think nervousness can make micturition more difficult?

Answer Nervousness invokes the “fight or flight” response in the body. When stressed, the ANS turns the body’s attention toward survival, making digestion and urination difficult.

Urinary Disorders

Case of the Crying Baby Initial symptoms: colic, constant crying, fever, rash, discharge, hernia How real are the reactions of the parents and medical professionals?

Duplex Kidney

Duplex Kidney/Collecting System Urinary defects can causes duplicated kidneys and ureters= more that normal number present Sometimes causes no symptoms Ureter can have dead end, stenosis (narrowing), or leaky valves, causing urine to back up into kidney, then infection

Renal Calculi (Kidney Stones) Made of crystals of calcium phosphate and uric acid that collect in renal pelvis, then break off into urine Larger stones can block ureters Causes severe pain: renal colic Other symptoms: nausea and vomiting, frequency, chills, fever, hematuria (blood in urine)

Renal Calculi Diagnosis by symptoms, ultrasound, or x-ray Rx –increase fluids to flush out stone, medications, and if needed LITHOTRIPSY Lithotripsy=Shock waves hit dense stones and break them up

Urinary Tract Infections Urethritis Cystitis Nephritis All inflammation/infection of different parts of Urinary system

Urethritis Inflammation of urethras Caused by bacterial infection, often Gonorrhea or Chlamydia More common in males

Cystitis Inflammation of the mucous membrane lining of the urinary bladder Caused by bacteria – usually E.Coli Sym- DYSUIA (painful urination) and frequency Usually in females (shorter urethra) Rx - antibiotics

Nephritis Inflammation of the kidney (kidney infection) Usually caused by bacteria Can also result from virus, fungus, calculi, tumors, or pregnancy

Hemodialysis Used for kidney failure Involves the passage of blood through device with semipermeable membrane Dialysis serves as substitute kidney Blood from patient flows through machine and is filtered Can be done at home or in clinic Takes 2-4 hours, 2-3 times a week.

What is Kidney Failure? Causes? Stages? Treatment? Prognosis?