Anatomy Lecture: Urinary System PART A

Main purpose of urinary system:

To remove wastes from the body and maintain homeostasis

6 functions of the kidneys:

Volume, concentration, pH, metabolic, excretory, endocrine

Volume function of kidneys:

Regulates the amount of water kept in the bloodstream to maintain blood pressure

Concentration function of kidneys:

Manages concentration of ions in blood

pH function of kidneys:

Acid-base balance regulation via H+ and HCO3-

Metabolic functions of kidneys:

Make new glucose/glycose, store glucose, break apart stored glycogen

Excretory functions of kidneys:

Gets rid of urea and creatine from muscle metabolism

Urea:

Product from breakdown of proteins into amino acids

Endocrine functions of the kidneys:

Produces reninn

Reninn:

Hormone that helps retain blood volume by managing Na+ and erythropoietin

Erythropoietin:

Signals production of RBCs

Kidneys main role in urinary system:

filter blood and remove wastes

Skin’s main role in urinary system:

Gets rid of excess water and salt through sweat

Liver’s main role in urinary system:

Breaks down toxins and produces urea

What cavity is the bladder located in?

pelvic cavity

Why is the left kidney more superior to the right one?

Due to the liver occuping the superior space of the right kidney

What body cavity is the kidneys located in?

The retroperitoneal

What is the name of the peritoneum that separates the kidneys from the digestive organs?

The parietal peritoneum

Why is perienal fat found in the renal sinus?

To provide insulation/protection

What can happen to your kidneys if there is too much perienal fat?

It can compress the kidneys and cause them to secrete inflamatory chemicals

Renal cortex:

Outer part of kidney

Renal medulla:

Inner part of kidney containing renal pyramids, ureters, etc

Ureter:

Takes urine from kidneys to bladder

Major calyx:

Connects minor calyx to ureter

Minor calyx:

Connects renal pyramids to major calyx

How much blood filters through the kidneys per min?

1.2-1.5 L

Nephrons:

Microscopic filtering units which clear waste from the blood and form urine

How many nephrons are approximately in each kidney?

1 million

What percent of a kidney is made up of cortical and juxtamedullary nephrons?

85% cortical, 15% juxtamedullary

Which has a longer loop of henle, cortical or juxamedullary nephrons?

Medullary nephrons

What are cortical nephrons surrounded by?

Peritubular capillaries

What is a juxtamedullary nephron surrounded by?

Vasa recta which runs parallel to the loop

Glomerulus:

Bundle of artieres of unfiltered blood that becomes filtered through tubules