Nephrons Flashcards
What does blood entering the kidneys for filtration pass through?
Knots of capillaries called glomeruli.
Where are the glomeruli contained within?
The bowman’s capsule.
What is filtered out of the blood in the glomerulus?
Almost all the constituents of plasma are filtered out of the blood, with the notable exception of large molecular weight proteins (>64KDa).
What molecules are re absorbed?
Useful molecules such as glucose and ions.
What happens in the proximal convoluted tubule?
Any substances that are useful to the body such as glucose and ions are reabsorbed.
What happens in the loop of Henle?
Water is reabsorbed.
What happens in the distal convoluted tubule?
Any waste products that were not filtered out in the capsule are secreted into the lumen of the nephron.
Where are the tubules and loop of henle located?
Proximal and distal tubules sit in the cortex, loop of henle passes through the medulla.
What happens in the collecting duct?
Water and ions are reabsorbed into the blood.
What controls the volume of urine produced?
The reabsorption in the collecting duct controls the volume of urine produced, the amount of water reabsorbed at the other sites remains constant.
What makes the collecting duct more permeable, allowing reabsorption of water?
The action of antidiuretic hormone released from the posterior pituitary.
Where does the blood supply of the kidney come from?
The renal arteries which are two large branches of the abdominal aorta that arise just below the level of L1.
What is the passage of the arterioles from the renal arteries on all the structures within the kidney?
The renal arteries divide into Afferent arterioles which feed into the glomeruli. Efferent arterioles run from the gromeruli and wrap around the nephron. Around the loop of henle these are called the vasa recta. The vasa recta drains into the renal veins which empty into the inferior vena cava.
