Week 18 / Renal system 1

Question 1

What organs are part of the urinary system ? [4]

Answer 1

Kidney :Produces urine and regulates body fluids

Ureter: Transport urine to bladder

Urinary bladder: reservoir for urine

Urethra: transport the urine to the outside

Question 2

Which organ is present in woman and not men in the urinary system ?

Answer 2

Ovary , left and right

Question 3

What are the shape of kidney ?

Answer 3

Paired , Bean shaped

Question 4

Where is the location of kidney ?

Answer 4

Located along the back body wall below the diaphragm and adjacent to the vertebral column

Question 5

Why is the right kidney lower than the left one ?

Answer 5

Because the left one occupies more space

Question 6

Whats the renal cortex?

Answer 6

the outer layer of the kidney, responsible for filtering blood and starting urine formation.

Question 7

Whats is the renal medulla ?
[what does it consist of]

Answer 7

the inner region of the kidney, consisting of cone-shaped structures called renal pyramids. It plays a key role in concentrating urine by reabsorbing water and electrolytes.

Question 8

What is the renal columns?

Answer 8

extensions of the renal cortex that project inward between the renal pyramids in the kidney. They provide structural support and house blood vessels that supply the renal cortex and medulla.

Question 9

What is the renal papilla

Answer 9

the tip of a renal pyramid in the kidney, where urine flows from the collecting ducts into the minor calyx.

Question 10

What is the renal capsule?

Answer 10

a tough, fibrous outer layer that surrounds the kidney, providing protection and maintaining its shape.

Question 11

What is the nephron?
What does it consist of? [6]

Answer 11

the functional unit of the kidney, responsible for filtering blood and forming urine.

It consists of the glomerulus, Bowman’s capsule, proximal tubule, loop of Henle, distal tubule, and collecting duct.

Question 12

Whats is the path of urine drainage ? [6]

Answer 12

1-Collecting duct
2-Minor calyx
3-Major calyx
4-Renal pelvis
5-Ureter
6-Urinary bladder

Question 13

What is the renal hilum?

Answer 13

The central indentation on the medial side of the kidney where structures such as the:
renal artery, renal vein, ureter, and nerves enter or exit the kidney.

Question 14

How do arterial flow into and venous flow out of the kidneys compare?

Answer 14

They follow similar paths, with arteries delivering blood to the kidneys and veins carrying filtered blood away, often running parallel to each other.

Question 15

How is the nerve supply to the kidneys provided?

Answer 15

The nerve supply is via sympathetic fibers from the renal plexus.

Question 16

What is the pathway of blood flow through the kidneys?

Answer 16

Artery:
1. Aorta
2. Renal artery
3. Segmental artery
4. Interlobar artery
5. Arcuate artery
6. Cortical radiate artery
7. Afferent arteriole
8. Glomerulus (capillaries)
9. Efferent arteriole
10. Peritubular capillaries and vasa recta
Vein:
11. Cortical radiate vein
12. Arcuate vein
13. Interlobar vein
14. Renal vein
15. Inferior vena cava

Question 17

What are the functions of kidney ? [3]

Answer 17

• Removal of toxins, metabolic wastes, and excess ions from the blood

*Regulation of blood volume, chemical composition, and pH

*Activation of vitamin D

Question 18

During Prolonged fasting what does the kidney do?

Answer 18

gluconeogenesis , by producing glucose from non-carbohydrate sources, such as amino acids, to help maintain blood glucose levels when liver glycogen stores are depleted.

Question 19

What are the endocrine functions of the kidney ? [2]

Answer 19

Renin: regulation of blood pressure and kidney function

Erythropoietin: regulation of BC production

Question 20

When PTH increases what happens? [3]

Answer 20

Increase in bone resorptions
Decrease in calcium
Increase in phosphate

Question 21

What are the functions of Nephron?

How many nephrons per kidney?

What does each nephron consist of ? [2]

Answer 21

the structural and functional units that form urine.

1 million

Renal corpuscle: The initial filtering component.

Renal tubule: Extends from the renal corpuscle and processes the filtrate.

Question 22

Nephron:
What type of layer is surrounds the glomerular capsule?

Answer 22

parietal layer

Question 23

Nephron:
What are the components of the glomerulus and glomerular capsule in the nephron? [4]

Answer 23

• Basement membrane: A layer that supports the glomerular filtration barrier.
• Podocytes: Specialized cells with foot-like processes that wrap around the capillaries of the glomerulus.
• Fenestrated endothelium: The capillary walls of the glomerulus with pores that allow filtration.
• Glomerular capsule (visceral layer): The inner layer of the capsule that directly covers the glomerulus

Question 24

Nephron:
What are the key features of cells in the proximal convoluted tubule (PCT)? [3]

Answer 24

Microvilli: Increase the surface area for absorption.

Mitochondria: Provide energy for active transport processes.

Highly infolded plasma membrane: Enhances the cell’s ability to absorb substances from the filtrate.

Question 25

Where is the proximal convoluted tubule located and what is its function?

Answer 25

The proximal convoluted tubule (PCT) is located in the cortex of the kidney.
It is responsible for the reabsorption of water, ions, nutrients, and other small molecules from the filtrate back into the bloodstream.

Question 26

Nephron:
What are the thick and thin segments of the Loop of Henle in the medulla?

Answer 26

Thick segment: Located in the ascending limb, it actively reabsorbs ions like sodium and chloride, and is impermeable to water.

Thin segment: Found in the descending limb, it allows passive reabsorption of water and is permeable to water but not to ions.

Question 27

Nephron:

What are the components of the Loop of Henle?

Answer 27

• Descending limb: The part of the loop that extends down into the medulla, where water is reabsorbed.
• Ascending limb: The part of the loop that ascends back toward the cortex, where sodium and chloride ions are actively reabsorbed, but it is impermeable to water.

Question 28

Nephron:
What are the components of the renal corpuscle? [2]

Answer 28

Glomerular capsule (also called Bowman’s capsule): The structure that surrounds the glomerulus and collects the filtrate.

Glomerulus: A network of capillaries where blood filtration begins.

Question 29

Nephron:
What are the types of cells in the collecting duct?

Answer 29

Principal cells: Involved in sodium and water reabsorption, as well as potassium secretion. They help regulate fluid and electrolyte balance.

Intercalated cells: Involved in acid-base regulation, primarily by secreting hydrogen ions or bicarbonate ions to maintain pH balance.

Question 30

Q: What percentage of nephrons are cortical nephrons?

Q: Where are the renal corpuscles of cortical nephrons located?

Q: How long are the loops of Henle in cortical nephrons?

Q: What is unique about the ascending limb of the loop of Henle in cortical nephrons?

Q: Where do cortical nephrons receive their blood supply from?

Answer 30

A: About 80-85% of the 1 million nephrons.

A: In the outer portion of the cortex.

A: They have short loops that only penetrate a small way into the medulla.

A: It consists only of a thick segment and lacks any thin portions.

A: From peritubular capillaries that arise from efferent arterioles.

Question 31

Q: What percentage of nephrons are juxtamedullary nephrons?

Q: Where are the renal corpuscles of juxtamedullary nephrons located?

Q: How long are the loops of Henle in juxtamedullary nephrons?

Q: What is unique about the ascending limb of the loop of Henle in juxtamedullary nephrons?

Q: Where do juxtamedullary nephrons receive their blood supply from?

Answer 31

A: About 15-20% of the nephrons.

A: Deep in the cortex, close to the medulla.

A: They have long loops of Henle that extend into the deepest region of the medulla.

A: It consists of both thin and thick segments.

A: From the vasa recta, which arises from peritubular capillaries before becoming peritubular venules.