Urinary System Flashcards

Flashcards reviewing the organs and functions of the urinary system.

What are the main organs of the urinary system?

Kidneys, ureters, urinary bladder, and urethra.

What are the primary functions of the urinary system?

Removal of waste products from blood, storage & expulsion of urine, and regulation of blood volume, erythrocyte production, ion levels, and acid-base balance.

What is the role of the kidneys in waste removal?

Filters the blood plasma to remove waste products and convert the resulting fluid into urine.

What is the function of the ureters?

Transports urine from the kidneys to the urinary bladder.

What is the role of the urethra?

Transports urine from the urinary bladder and expels it from the body through micturition/urination.

How do kidneys control blood volume?

Specific hormones and indirect influence on blood pressure changes.

What happens when the kidneys detect reduced oxygen levels in the blood?

It releases erythropoietin, which stimulates the production of erythrocytes (red blood cells).

What ions do the kidneys help control in the blood?

Sodium, potassium, calcium, and phosphate.

What ions are controlled by the kidneys to regulate blood's acid-base balance?

Hydrogen and bicarbonate ions.

Where are the kidneys located?

Paired retroperitoneal organs in the abdominal cavity, approximately between T12 and L3.

What is the primary function of the kidneys?

Regulate blood and remove waste products from the blood to produce urine.

What are the three tissue coverings of the kidneys?

Renal fascia, perirenal fat capsule, and fibrous capsule.

What is the function of the renal fascia?

Anchors the kidney to the posterior abdominal wall.

What is the function of the perirenal fat capsule?

Provides support to the kidneys, helping to keep it in place.

What is the function of the fibrous capsule?

Maintains the kidney's shape, provides protection from traumatic injury, and helps prevent infections from entering the kidney.

What are the two main regions of the internal anatomy of the kidneys?

Renal cortex (outer region) and renal medulla (inner region).

What are renal pyramids?

Structures that make up the renal medulla (8-15 per kidney).

What are renal columns?

Extensions of the renal cortex that project into the renal medulla between renal pyramids.

What is the renal papilla?

Apex of the renal pyramid.

What is a renal lobe?

Region of a kidney consisting of a renal pyramid and its surrounding cortical tissue.

What is a minor calyx?

A funnel-shaped space that each renal papilla projects into.

What do several minor calyces merge to form?

Merge to form a single space called the renal pelvis, which is continuous with the ureter.

What is the origin of the renal artery?

Branch of the abdominal aorta.

What is the role of the afferent arteriole?

Blood vessel that delivers blood to the nephron.

What is a nephron?

Functional unit of the kidney that filters blood plasma to produce urine.

What is the glomerulus?

Capillary network within the nephron where filtration of blood plasma occurs.

What are the three main processes performed by the nephron?

Filtration, reabsorption, and secretion.

What and where is the renal corpuscle?

Part of nephron where filtration of blood plasma occurs.

What are the two components of the renal corpuscle?

Glomerulus and the glomerular (Bowman's) capsule.

What is the renal tubule?

Part of nephron where reabsorption and secretion occur.

What are the three components of the renal tubule?

Proximal convoluted tubule, loop of Henle, and distal convoluted tubule.

What is the glomerular (Bowman's) capsule?

Surrounds the glomerulus; outer parietal layer made of simple squamous epithelium and inner visceral layer made of podocytes.

What is the capsular space?

Where filtrate collects before flowing into the proximal convoluted tubule.

What is the Loop of Henle involved in?

Reabsorption of water and essential solutes back into the blood and some secretion of hydrogen ions into tubular fluid.

Into what structures the tubular fluid drain into, after leaving the nephron?

Collecting tubules, collecting ducts, and papillary ducts.

What is the function of the ureters?

Transport urine from the kidneys to the urinary bladder.

What are the three layers of the ureters?

Inner mucosa, middle muscularis, and outer serosa or adventitia.

What is the mucosa of the ureters composed of?

Composed of transitional epithelium to allow for stretching.

What helps anchors the ureters to the posterior abdominal wall?

Anchors ureters to the posterior abdominal wall.

What is the urinary bladder?

Muscular sac that stores urine until it is ready to be expelled.

What is the role of rugae in the urinary bladder?

Increases distensibility of the urinary bladder.

What is the function of the detrusor muscle?

Squeezes urine out when it contracts during micturition.

What is the urethra?

Tube that transports urine from the urinary bladder to expel it.

What is the internal urethral sphincter?

Involuntary sphincter that keeps the urethra closed when urine is not being expelled.

What is the external urethral sphincter?

Voluntary sphincter composed of circularly arranged skeletal muscle fibers.

What are the two functions of the male urethra?

Transport urine out of the body and conduct semen during ejaculation (but NOT at the same time).

What are the three regions of the male urethra?

Prostatic, membranous (intermediate), and spongy urethra.