Exam 1 Flashcards
The urinary system is composed of four main components:
the kidneys, where urine is formed from the filtration of blood
the ureters that carry the urine to the bladder
the bladder that stores the urine produced
the urethra that delivers the urine for excretion outside the body
Primary function of kidneys
Removal of waste products
Acid-base balance
Retention of essential nutrients
Water, electrolyte balance
Hormone production
Production of vitamin D
Functional Unit of Kidney
Nephron
Two types of nephrons
Cortical nephrons
Juxtamedullary nephrons
This is controlled in the nephron by the following renal functions:
-renal blood flow
-glomerular filtration
-tubular reabsorption
-tubular secretion
% of the blood leaving the left ventricle of the heart enters the kidneys via the renal arteries.
20-25
Afferent arteriole means
Blood enters
Efferent arteriole means
Blood exits
the major exchanges of water and salts take place
Loop of Henle
Factors that influence filtration
Cellular structure of capillary walls
Hydrostatic pressure
Oncotic pressure
Renin-Angiotensin-Aldosterone system (RAAS)
Three cell layers of glomerulus
Capillary wall membrane
Basement membrane
Visceral epithelium
Shield of Negativity
cations and neutral pass thru repels anion plasma proteins
Hydrostatic pressure:
Pressure exerted by liquid = enhances filtration
Oncotic pressure:
Pressure exerted by the presence of unfiltered plasma proteins in glomerular capillaries
“the osmotic pressure of a substance in solution caused by the presence of colloids”
Systemic BP ↓
Less blood flowing into kidney
Toxic materials accumulate in blood