Lecture 37 Flashcards
what are the 5 main functions of kidneys
Fluid and ion homeostasis
Waste excretion
Drug removal
Hormone production
Glucose synthesis
what percentage of cardiac output enters kidney
20%
what is The Nephron
Functional unit of the kidney; where fluid control occurs
what are the parts of the nephron
Renal corpuscle:
Made of the glomerulus and Bowman’s capsule
Tubule:
Proximal
descending/ascending Loop of Henle
Distal
Collecting duct
The Pathway of Filtration through Nephrons
Renal corpuscle
Proximal tubule
Loop of Henle
Distal Tubule
Collecting Duct
Renal blood supply pathway
Renal Artery
Afferent Arteriole
Glomerulus (i.e., capillaries)
Efferent Arteriole
Peritubular Capillaries Or Vasa Recta
Venules
Renal Vein
what are the two types of nephron
Cortical and Juxtamedullary nephrons
how is the Type of nephron is dictated
by the length of the Loop of Henle
Cortical nephrons:
Located in outer ⅔ of cortex
80%
Juxtamedullary nephrons:
Located in inner ⅓ of cortex
Long Loop of Henle
Produce concentrated urine
20%
3 Critical Functions of Nephrons
Filtration: The first function of nephrons is to filter blood plasma. The glomerulus, a cluster of blood vessels, filters blood through a semipermeable membrane, which allows water, ions, and small molecules to pass through but prevents larger molecules like proteins from passing through. The filtered blood enters the Bowman’s capsule and forms a filtrate, which contains water, glucose, salts, and waste products.
Reabsorption: The second function of nephrons is to reabsorb useful substances from the filtrate back into the blood. The filtrate passes through a series of tubules where various substances like glucose, amino acids, and electrolytes are reabsorbed into the blood. This process helps maintain the body’s fluid and electrolyte balance.
Secretion: The third function of nephrons is to secrete waste products and excess ions into the filtrate. Substances like creatinine, urea, and excess ions like potassium and hydrogen are secreted from the blood into the filtrate to be excreted from the body in urine. This process helps regulate the body’s acid-base balance and removes waste products from the body.
3 Critical Functions of Nephrons
Filtration: The first function of nephrons is to filter blood plasma. The glomerulus, a cluster of blood vessels, filters blood through a semipermeable membrane, which allows water, ions, and small molecules to pass through but prevents larger molecules like proteins from passing through. The filtered blood enters the Bowman’s capsule and forms a filtrate, which contains water, glucose, salts, and waste products.
Reabsorption: The second function of nephrons is to reabsorb useful substances from the filtrate back into the blood. The filtrate passes through a series of tubules where various substances like glucose, amino acids, and electrolytes are reabsorbed into the blood. This process helps maintain the body’s fluid and electrolyte balance.
Secretion: The third function of nephrons is to secrete waste products and excess ions into the filtrate. Substances like creatinine, urea, and excess ions like potassium and hydrogen are secreted from the blood into the filtrate to be excreted from the body in urine. This process helps regulate the body’s acid-base balance and removes waste products from the body.
The pathway for glomerular filtration
Movement of filtrate
Through the pores between endothelial cells
Through the basement
membrane matrix
Through the
podocyte filtration slits