Chapter 26 - The Urinary System

Is blood flow through the kidney the same as urine flow?

No, it is not

Where in the body does blood for the arteries come from to the kidneys?

Abdominal aorta

Where in the body does blood flow from the kidneys go to?

Inferior vena cava

What is the order of arteries to the glomerulus starting from the abdominal aorta?

Renal artery → Segmental (lobar) arteries → Interlober arteries → arcuate artery → CRA (interlobular) artery → vasa recta

How does blood leave the kidney?

Interlobular vein → Arcuate vein → interlobar vein → renal vein → IVC

What are the blood supplies that go into the glomerulus?

Afferent and efferent arterioles

What muscle leads the afferent arteriole to the glomerulus?

The sphincter muscle

What is a glomerulus?

A ball of fenestrated capillaries

What surrounds in the visceral layer of the glomerulus?

Podocytes with pedicells that have filtration slits which is the action of the glomerulus

How does urine leave the glomerulus?

PCT → DL → AL → DCT → CD

What is apart of the nephron loop?

The descending and ascending limb

Where do all distal convoluted tubules exit with their urine?

Into the collecting ducts (multiple DCT’s enter into one collecting duct)

What covers a kidney?

Multiple layers of deep fascia and fat (capsule, perirenal fat, adipose capsule, and perarenal fat)

How do you damage your kidneys?

By damage to the posterior abdominal cavity

How many pyramids should you roughly have?

~5

Where is the base of a renal pyramid?

Close to the cortex

Where is the apex of a renal pyramid?

At the renal papilla

How do the ureters enter the urinary bladder?

Posteriorly

Where do most bladder problems come from?

The trigone area of the urinary bladder

What are the vital excretory functions performed by the urinary system?

• Regulating plasma concentrations of ions

• Regulating blood volume and blood pressure by adjusting the volume of water lost in the urine, releasing erythropoietin, and releasing renin

• Contributing to the stabilization of blood pH

• Conserving valuable nutrients

• Eliminating waste products

• Synthesizing calcitriol

• Assisting the liver in detoxifying poisons

Can we live without your kidneys?

NO, but you can live without one

What is typical blood pH?

7.35/7.45

What are two issues based on blood with the kidney?

1. More urine = more blood, high BP

2. Less urine = less blood, low BP

Are the kidneys retroperitoneal?

Yes, they are behind the body wall

Is the left kidney higher than the right?

Yes, it is because of the liver on the right

How many nephrons are there?

Millions

How does the ureter transport urine toward the urinary bladder?

Peristalsis

What do kidney stones block?

Calyces

Where does the suparenal artery go after it branches off the renal artery?

The suparenal gland

What is the segmental artery also called?

Lobar artery

Where does the renal vein go?

To the IVC to the heart

Blood flow through the kidney from renal artery → renal vein

1. Renal Artery

2. Segmental (lobar) arteries

3. Interlobar arteries

4. Arcuate arteries

5. Cortical radiate arteries (interlobular arteries)

6. Afferent arterioles

7. Glomerulus

8. Efferent arteriole

9. Peritubular capillaries (VASA RECTA)

10. Venules

11. Interlobular veins

12. Arcuate veins

13. Interlobar veins

14. Renal vein

Where does filtration occur in the glomerulus?

Visceral layer of podocytes and pedicells that cover the glomerulus with filtration slits

Where does the collecting duct take the urine to?

The minor calyces

Where does filtration occur in the blood?

Vasa recta, peritubular capillaries

What color should your urine be in the collecting duct?

Clear yellow, not blood (if it is dark or there is blood you could be dehydrated or there is kidney damage)

Is the efferent arteriole thinner or thicker than the afferent?

Thinner, because you are secreting out ions, nutrients and water, so as it leaves the BP must remain the same

Where is urine carried after filtrated in Bowman’s capsule?

Capsular space

Does the uterus lie retroperitoneally?

Yes, it does

What are rugae in the urinary bladder?

Invaginations in mucosa

What is the internal urethral sphincter made out of?

Smooth muscle

What is the external urethral sphincter made out of?

Skeletal muscle

Should urination be voluntary?

Yes, but there are cases where it is not (men with prostate gland malfunction and children)

Are females or males harder to give a catheter to?

Females

What do contractions do in the bladder?

Move urine to the posterior wall of the bladder

what happens as you age with the bladder?

• Decline in number of functional nephrons

• Reduction in glomerular filtration

• Reduced sensitivity to ADH

• Loss of tone in sphincter muscles leading to incontinence

• Strokes, Alzheimer’s disease, or other CNS problems impair ability to control bladder reflex

• Urinary retention may develop in men whose prostate glands are enlarged.