1Q: What are the two major components of a nephron?
A:
• Glomerulus (filtering system)
• Tubule (processing system)
2Q: What happens to substances as liquid moves through the nephron?
A: Useful substances are reabsorbed; wastes are excreted
3Q: What structures make up the renal corpuscle?
A:
• Glomerulus
• Bowman’s capsule
4Q: Where does blood enter the glomerulus?
A: Through the afferent arteriole
5Q: Where does blood leave the glomerulus?
A: Through the efferent arteriole
6Q: What happens to water and solutes in the glomerulus?
A: They are filtered into Bowman’s space
7Q: What segments make up the renal tubule?
A:
• Proximal convoluted tubule
• Loop of Henle
• Distal convoluted tubule
8Q: Where does urine finally drain before entering the bladder?
A: From collecting ducts → papillary ducts → renal pelvis → ureter → bladder
9Q: What structures make up the renal tubule?
A: The nephron and the collecting tubules.
10Q: Where does urine formation occur and where is it emptied?
A: Urine formation occurs in the renal tubule and is emptied into the renal pelvis.
11Q: How many nephrons are found per kidney?
A: Approximately 1 to 1.5 million nephrons per kidney.
12Q: What structures does each nephron consist of?
A:
• Glomerulus
• Bowman’s capsule
• Proximal convoluted tubule
• Loop of Henle
• Distal convoluted tubule
13Q: What is the juxtaglomerular complex?
A: A specialized collection of two cell types: macula densa cells and juxtaglomerular cells.
14Q: Where is the juxtaglomerular complex located?
A: At the juncture of the afferent and efferent arterioles with a portion of the distal convoluted tubule of the nephron.
15Q: What are the three major functions of the juxtaglomerular complex?
Regulation of systemic blood pressure and blood volume via the renin–angiotensin system
Local control of glomerular filtration rate (GFR) by tubuloglomerular feedback using nitric oxide (NO)
Hematopoiesis via erythropoietin production by peritubular capillary endothelium cells of the kidney
16Q: What is the glomerulus?
A: A network of capillary endothelial cells covered by a layer of specialized epithelial cells (podocytes).
17Q: What function do podocytes perform?
A: They allow water and small dissolved solutes to pass into the capsular space of the renal corpuscle through filtration slits.
18Q: What is unique about the glomerular capillaries?
A: They have unusually high blood pressure.
19Q: Why is high blood pressure necessary in the glomerulus?
A: To maintain an effective glomerular filtration rate (GFR) for plasma filtrate production.
20Q: Approximately how many capillaries does a single glomerulus contain?
A: About 50 capillaries.
21Q: What is the total surface area of all glomerular capillaries in both kidneys?
A: Approximately 2.0 m².
22Q: How much filtrate is produced daily by the glomeruli?
A: Approximately 45 gallons (180 liters) per day.
23Q: What is another name for Bowman’s capsule?
A: The glomerular capsule.
24Q: What structure does Bowman’s capsule surround?
A: The glomerulus.
25Q: What type of structure is Bowman’s capsule?
A: A double-walled cup.
26Q: What cells compose the inner (visceral) layer of Bowman’s capsule?
A: Podocytes.
27Q: What do podocytes form to assist filtration?
A: Foot processes that interdigitate to form filtration slits.
28Q: What is the function of the filtration slit system?
A: To act as a filtration barrier that restricts passage of large molecules.
29Q: What is the proximal convoluted tubule responsible for?
A: Reabsorption of the majority of the filtrate.
30Q: Approximately what percentage of the glomerular filtrate is reabsorbed in the PCT?
A: About 75%.
31Q: Where is the proximal convoluted tubule primarily located?
A: In the cortex of the kidney.
32Q: What type of epithelial cells line the PCT?
A: Cuboidal and pyramidal epithelial cells.
33Q: What surface feature enhances reabsorption in the PCT?
A: Microvilli on the luminal surface of epithelial cells.
34Q: What substances are reabsorbed in the PCT?
A:
• Glucose
• Amino acids
• Inorganic solutes
• Water
35Q: Where is the loop of Henle located?
A: In the medulla of the kidney.
36Q: What is the shape of the loop of Henle?
A: A hairpin curve.
37Q: What segments make up the loop of Henle?
A:
• Descending thin segment
• Ascending thick segment
38Q: Why is the permeability of the loop of Henle important?
A: It allows diffusion and transport phenomena to concentrate the urine.
39Q: What role does the medullary interstitial fluid play?
A: Its high concentration helps produce concentrated urine.
40Q: What effect does the loop of Henle have on urine volume and concentration?
A: Produces low volume, concentrated urine.
41Q: How does the distal convoluted tubule compare structurally to the PCT?
A: It has fewer convolutions.
42Q: What type of epithelial cells line the DCT?
A: A single layer of cuboidal cells.
43Q: What happens to urine in the distal convoluted tubule?
A: It is converted into collecting tubule fluid.
44Q: Which hormone affects the distal convoluted tubule?
A: Antidiuretic hormone (ADH).
45Q: What does aldosterone do in the distal tubule?
A:
• Increases sodium and chloride reabsorption
• Increases excretion of hydrogen, potassium, and ammonia ions
46Q: What do collecting tubules receive?
A: Fluid from the distal convoluted tubules.
47Q: Where do collecting tubules transport fluid?
A: To the calyces of the renal pelvis.
48Q: How do collecting tubule cells respond to ADH?
A: They reabsorb water.
49Q: What is the effect of water reabsorption in collecting tubules?
A: Increases the concentration of the fluid.
50Q: What is the fluid called after it is delivered to the calyces?
A: Urine.