Exam 3 LO Flashcards
What are the two kinds of nephrons?
- Cortical= 80%, short loops of henle (reabsorption)
- Juxtamedullary= 20%, long loops of Henley ( control urine concentration)
Renal cortex and renal medulla: iso-osmotic or hyper osmotic
Cortex= iso-osmotic and medulla= hyper-osmotic
Describe bowman’s capsule
Encloses glomerular fenestrated capillaries
The proximal convoluted tubule within the
Loop of henle within the
Distal tubule within the
Renal cortex
Extends into medulla then to cortex
Renal cortex
Fluid from renal corpuscle enters ___
Proximal tubule
Contains the ascending and descending loops
Loop of henle
Fluid enters __ from loop of henle
Distal tubule
The distal tubule contains what cells? What do those cells do?
Macula densa cells, sense ions
Forms ducts that drain into major calyces
Collection duct
Carries blood to the glomerulus, entering the capillary
Afferent arteriole
Capillary network, positioned between 2 arterioles
Glomerulus
Carries blood away from the glomerulus (leaving capillary)
Efferent arteriole
What cells do the afferent arteriole contain? Function of cells?
Juxtaglomerular cells, sense mean arterial pressure
Short loops of henle of cortical nephrons that extend from cortex to medulla
Peritubular capillaries
What is the juxtaglomerular apparatus?
Coordinates ions and blood pressure; macula densa cells plus juxtaglomerular cells
Explain the slits of podocytes
Surrounded by glomerular capillaries, contain pedicels and wrap around capillaries (spaces between pedicels are filtration slits)
Describe the fenestrated endothelium (glomerular endothelial cells) of the filtering membrane
allows for filtration of ions, water, small molecules, single amino acids, and drugs
What is the GFR?
Measure of kidney function, amount of filtrate formed per minute (120-125 mL/min)
What is the major determinant of GFR
Glomerular capillary hydrostatic pressure (P gc)
What is the GFR regulated by
Auto regulation of intrinsic factors, tubuloglomerular feedback, and extrinsic factors (neural and hormones)
Extrinsic factors regulate what
Blood pressure
What is RAAS
Renin, angiotensin, aldosterone, system
Ways to increase the GFR?
- Vasoconstrict efferent arteriole
- Vasodilator afferent arteriole
(Increase filtration: increase Pgc)
Ways to decrease GFR?
- Vasoconstrict afferent arteriole
- Vasodilate efferent arteriole (blood flowing out of capillary increases)