Phys. II Test One: Renal Flashcards
What is the function of the kidneys?
Regulate ECF water and concentrations of ions and regulate acid base balance as well as remove metabolic wastes.
What is gluconeogenesis?
During fasting glucose is synthesized from other molecules such as amino acids and released into the blood to keep blood glucose up.
What is the functional unit of the kidney?
Nephron. Which is made up of the renal corpuscle and renal tubule
What is the filtering component of the nephron?
Renal corpuscle
What extends out from the corpuscle and is surrounded by peritubular capillaries?
Renal tubule
What does the renal corpuscle consist of?
Glomerular capillaries with bowmans space and bowmans capsule
Where are renal corpuscles found?
Within the renal cortex
Where do Juxtamedullary nephrons have corpuscles?
Near the cortex/medulla junction
Where do cortical nephrons have their corpuscles?
Near the kidney surface
The renal tubule’s lumen is a continuation of what?
The space in Bowman’s capsule
What is the proximal tubule?
The first section of the tubule, it drains Bowmans capsule
What is the loop of henle?
The section following the proximal tubule it has a descending limb followed by an ascending limb
What is the distal convoluted tubule?
The section that follows the loop of henle ascending limb
What is the collecting duct?
The duct where the convoluted distal tubule drains. It is composed of a cortical collecting duct followed by a medullary collecting duct. IT contains the fluid that will be transported to the bladder and eliminated.
Afferent arteriole?
Carriesx blood into the glomerular capillaries
What is the efferent arteriole and what makes it?
Arteriole through which blood leaves the capillaries and it is formed by the glomerular capillaries recombining.
What does the efferent arteriole divide into?
Peritubular capillaries
What type of substances are filtered across the glomerular membrane?
Low molecular weight substances such as water, glucose, urea, and ions.
What is glomerular filtration?
The process of low weight molecular substances in the glomerular capillary plasma being filtered across the membrane of the capillaries and bowmans capsule into the space. This produces glomerular filtrate and will contain the substances in the same concentrations that they are found in the plasma.
Are there cells or proteins in the filtrate?
Neither because they are both too large to cross the membrane.
What is tubular re-absorption?
Selective movement of filtered substances from tubular lumen into the peritubular capillaries
What is tubular secretion?
Selective movement of nonfiltered substances from peritubular capillaries into the tubular lumen.
Give an example of total excretion?
Substance X is freely filterable and can’t be reabsorbed and undergoes 100% secretion
What is partial excretion?
When a substance is filterable and undergoes partial reabsorption and can’t be secreted
When would no excretion occur?
When a substance is filterable but undergoes 100% reabsorption and can’t be secreted. For example glucose.
What are filtration slits?
Spaces between foot processes
What is the force that drives filtration?
Glomerular capillary fluid pressure that is high comparted to pressure in other capillaries.
*Pressure gradient
What two forces oppose filtration?
The hydrostatic pressure in bowman’s space and the osmotic force from proteins in the plasma that aren’t seen in Bowman’s space.
What is the net pressure favoring filtration?
10 mmHg