Urinary system

What is the primary function of the urinary system?

To remove nitrogenous waste products from the blood and maintain the balance of water and electrolytes.

What are the main nitrogenous waste products filtered by the kidneys?

Urea, creatinine, and uric acid.

How much blood do the kidneys process daily?

About 200 quarts.

How much urine do the kidneys produce daily?

Approximately 2 quarts.

What is homeostasis in the context of the urinary system?

The ability of the kidneys to maintain an equilibrium of water, electrolytes, and acids in body fluids.

What enzyme do the kidneys secrete to regulate blood pressure?

Renin.

What hormone is produced by the kidneys to stimulate red blood cell production?

Erythropoietin (EPO).

What is the function of calciferol secreted by the kidneys?

It is the active form of vitamin D necessary for calcium absorption from the intestine.

What are the two main regions of the kidney?

The outer cortex and the inner medulla.

What is the hilum of the kidney?

A depression on the medial border where blood vessels and nerves enter and exit.

What is the role of the ureters?

To carry urine from the kidneys to the urinary bladder via peristaltic waves.

What is the urinary bladder's function?

To serve as a temporary reservoir for urine.

What is the trigone in the urinary bladder?

A triangular region at the base of the bladder where the ureters enter and the urethra exits.

What is the urethra's function?

To carry urine from the urinary bladder to the outside of the body.

What is urination also known as?

Voiding.

How long is the male urethra?

About 8 inches long.

How long is the female urethra?

About 2 inches long.

What is the function of arterioles in the kidneys?

To regulate blood flow through the kidneys.

What happens when blood pressure falls in the kidney vessels?

The kidney produces renin to increase blood pressure and restore blood flow.

What are the three steps in the formation of urine?

1. Glomerular filtration; 2. Tubular reabsorption; 3. Tubular secretion.

What is a nephron?

The functional unit of the kidney, consisting of a glomerulus and a renal tubule.

What substances are filtered during glomerular filtration?

Water, sugar, wastes (urea and creatinine), and sodium.

What is tubular reabsorption?

The process of reabsorbing water, sugar, and sodium back into the bloodstream.

What is tubular secretion?

The process of secreting acids, potassium, and drugs into the urine.

What is the average weight of a kidney?

About 4 to 6 ounces.

What surrounds each kidney for protection?

A cushion of adipose (fatty) tissue and fibrous connective tissue.

What is the function of the kidneys in hormone regulation?

To degrade and eliminate hormones such as insulin and parathyroid hormone from the bloodstream.

What is the functional unit of the kidney?

Nephron

What is the role of the glomerulus in the kidney?

It is a tiny ball of capillaries that filters blood to form urine.

What structure surrounds each glomerulus?

Glomerular (Bowman) capsule

What is the process of filtration in the kidneys?

It allows water, salts, sugar, and urea to pass through the glomerular filter while preventing large substances like proteins from entering urine.

What happens during reabsorption in the renal tubule?

Water, sugar, and sodium are returned to the bloodstream.

What substances are secreted into the renal tubule?

Potassium, acids, and drugs.

What is the composition of urine?

95% water and 5% urea, creatinine, salts, and acids.

What is the renal pelvis?

The central collecting region in the kidney where urine collects before moving to the ureter.

What is the function of the ureter?

It carries urine from the kidneys to the urinary bladder.

What is the role of the urinary bladder?

It temporarily stores urine.

What is the process of urination?

The expulsion of urine from the bladder, also called micturition.

What is the function of the renal artery?

It carries blood to the kidney.

What is the role of the renal vein?

It carries blood away from the kidney towards the heart.

What is creatinine?

A nitrogenous waste excreted in urine, produced from muscle metabolism.

What are electrolytes?

Chemical elements that carry an electrical charge when dissolved in water, necessary for muscle and nerve function.

What hormone is secreted by the kidney to stimulate red blood cell production?

Erythropoietin (EPO)

What is the significance of potassium (K+) in the body?

It is essential for muscle contraction and conduction of nervous impulses.

What is sodium (Na+) needed for?

Proper transmission of nerve impulses, heart activity, and other metabolic functions.

What is the trigone?

A triangular area in the urinary bladder.

What is urea?

A major nitrogenous waste excreted in urine.

What is the role of renin?

An enzyme secreted by the kidney that raises blood pressure by influencing vasoconstriction.

What is the medulla in relation to the kidney?

The inner region of the kidney.

What is a catheter?

A tube for injecting or removing fluids, such as draining urine from the bladder.

What is the cortex of the kidney?

The outer region of the kidney.

What are calyces?

Cup-like regions of the renal pelvis.

What is the significance of nitrogenous waste?

Substances containing nitrogen that are excreted in urine, such as urea, uric acid, and creatinine.

What percentage of cardiac output goes to the kidneys?

25%

How much fluid is filtered daily by the kidneys?

About 200 quarts (189 L)

What is the typical daily urine output?

About 2 quarts (1500 mL)

What does the combining form 'cali/o' or 'calic/o' refer to?

Calyx (cup-shaped structure)

What does 'cystitis' mean?

Inflammation of the urinary bladder, often caused by bacterial infections.

What is a 'cystectomy'?

Surgical removal of the urinary bladder.

What does 'glomerul/o' refer to?

Glomerulus

What is 'nephropathy'?

Disease of the kidney.

What does 'nephroptosis' mean?

Downward displacement or dropping of a kidney.

What is 'hydronephrosis'?

Distention of the renal pelvis due to obstruction of urine flow.

What does the combining form 'pyel/o' refer to?

Renal pelvis

What is 'renal colic'?

Intermittent spasms of pain caused by kidney stones.

What does 'trigonitis' refer to?

Inflammation of the trigone region of the bladder.

What is 'albuminuria'?

Presence of albumin in the urine, indicating kidney malfunction.

What does 'azotemia' indicate?

Elevated levels of nitrogen in the blood, characteristic of uremia.

What is 'polydipsia'?

Excessive thirst, often a sign of diabetes.

What does 'hyperkalemia' mean?

Excess potassium in the blood due to kidney failure.

What is 'ketosis'?

A condition characterized by the accumulation of ketone bodies in the blood.

What does 'nephrolithiasis' refer to?

Presence of kidney stones.

What is 'nocturia'?

Frequent urination at night.

What does 'oliguria' mean?

Scanty urine production.

What is 'uremia'?

Toxic state resulting from the accumulation of nitrogenous waste in the blood.

What does 'diuresis' refer to?

Increased urine production, often caused by diuretics.

What is 'antidiuretic hormone' (ADH)?

A hormone that promotes water reabsorption in the kidneys.

What does 'urinary incontinence' mean?

Loss of control over urination.

What is 'enuresis'?

Bed-wetting, a condition of involuntary urination.

What does 'lithotripsy' refer to?

Crushing of stones in the urinary tract.

What is incontinence?

The inability to hold back urination when feeling the urge to void.

What is urinary retention?

A condition where the outflow of urine from the bladder is blocked.

What does the suffix '-uria' refer to?

It refers to urination or urine condition.

What is dysuria?

Painful or difficult urination.

What is anuria?

The absence of urine production, commonly caused by renal failure or urinary tract obstruction.

What is hematuria?

The presence of blood in urine.

What is microhematuria?

Hematuria that is only visible under a microscope.

What is glycosuria?

The presence of glucose in urine, often a sign of diabetes mellitus.

What is polyuria?

Excessive urination, a symptom of both diabetes insipidus and diabetes mellitus.

What is the difference between enuresis and nocturia?

Enuresis is involuntary urination, while nocturia is voluntary frequent urination at night.

What is urinalysis?

An examination of urine to determine the presence of abnormal elements indicating various pathologic conditions.

What does normal urine color indicate?

Normal urine color is yellow (amber) or straw-colored; colorless urine indicates high water content.

What does cloudy urine indicate?

Cloudy or turbid urine indicates a urinary tract infection with pus (pyuria) and bacteria (bacteriuria).

What is the normal pH of urine?

Normal urine has a slightly acidic pH of 6.5.

What does the presence of albumin in urine indicate?

Albuminuria may indicate a leak in the glomerular membrane, suggesting kidney damage.

What is the significance of glucose in urine?

Glycosuria indicates diabetes mellitus, as excess sugar spills into urine due to hyperglycemia.

What does specific gravity measure in urine?

It reflects the amounts of wastes, minerals, and solids in the urine.

What is ketonuria?

The presence of ketones in urine, indicating fat breakdown for energy, often seen in diabetes mellitus.

What is nephrolithiasis?

The presence of kidney stones, which may require removal by lithotripsy or surgery.

What is glomerulonephritis?

Inflammation of the glomeruli within the kidney, which can lead to hematuria and renal failure.