Nephron Flashcards
What is the nephron,and what is its function?
The nephron is the structure in the kidney that filters blood to remove water, salts, and metabolic wastes.
What is the Bowman’s capsule, and what happens inside it?
The Bowman’s capsule is a cup-like structure in the nephron that surrounds the glomerulus and collects the filtrate.
What is the glomerulus, and why is its structure important?
The glomerulus is a network of capillaries inside the Bowman’s capsule; its high pressure helps filter plasma from the blood.
What is ultrafiltration, and how does it work?
Ultrafiltration is the process where high blood pressure forces plasma fluid through the glomerulus into the nephron, filtering out waste but retaining larger molecules.
What substances can pass through the fenestrated capillary walls of the glomerulus?
Water, salts, small molecules (like glucose), and metabolic waste (urea) can pass through the capillary walls, but larger molecules such as proteins and blood cells cannot.
What role does the basement membrane play in filtration?
The basement membrane acts as an additional filter, preventing large molecules from passing through while allowing smaller molecules to pass.
What are podocytes, and what is their function?
Podocytes are specialized cells that wrap around capillaries in the Bowman’s capsule and help with the filtration process.
What happens in the proximal tubule of the nephron?
In the proximal tubule, water, salts, and nutrients are selectively reabsorbed into the renal cortex.
What is the difference between passive and active transport in the proximal tubule?
Passive transport allows substances like water to move freely, while active transport requires energy to move solutes like glucose and salt.
How does the microvilli in the proximal tubule help with reabsorption?
Microvilli in the proximal tubule increase the surface area, enhancing the reabsorption of nutrients.
What is the function of the loop of Henle?
The loop of Henle creates a high solute concentration in the filtrate by removing water and salts, helping with urine concentration.
How does the loop of Henle create a high solute concentration?
The descending limb allows water to pass through, increasing solute concentration, while the ascending limb pumps out salts, reducing solute concentration.
What is the difference between the descending and ascending limbs of the loop of Henle?
The descending limb is permeable to water, while the ascending limb is permeable to salts but not water.
What happens in the distal tubule of the nephron?
In the distal tubule, water is reabsorbed by passive transport, while salts and ions are actively transported.
What is the collecting duct, and what happens to the filtrate there?
The collecting duct collects filtrate from multiple nephrons and reabsorbs water and some urea to maintain homeostasis.
