Chapter 38 Flashcards
Structure and Function of the Renal/Urologic & Digestive System
What are the primary functions of the Kidney’s?
- Maintain a stable internal environment for optimal cell and tissue metabolism.
- Balance solute and water transport.
- Excrete metabolic waste products.
- Conserve nutrients.
- Regulate acids and bases
What hormones do the kidneys secrete as their endocrine functions?
- Renin: Regulation of blood pressure
- Erythropoietin: Production of erythrocytes
- 1,25-dihydroxyvitamin D3: Metabolism of calcium
Synthesis of glucose from amino acids.
Gluconeogenesis
What substance forms in the kidneys and drains into the bladder?
Urine
Define the structure of the kidneys.
Paired organs located in the posterior region of the abdominal cavity behind the peritoneum (retroperitoneal).
What is a tightly adhering capsule that surrounds each kidney; each kidney is then embedded in a mass of fat.
Renal Capsule
What is the fibrous tissue that attaches each kidney to the posterior abdominal wall?
Renal Fascia
This is where the renal blood vessels, nerves, lymphatic vessels, and ureter enter and exit the kidneys.
Hilum
This is the outer layer of each kidney. It also contains all the glomeruli, most of the proximal tubules, and some segments of the distal tubule.
Renal Cortex
This is the inner part of each kidney that contains tubules and the collecting duct. It also consists of the regions called the pyramids.
Renal Medulla
Extends from the cortex down between the renal pyramids.
Renal Columns
Apexes of the pyramids that projects into a cup-shaped cavity that joins together to form a major calyx?
Minor Calyx
Joins to form the renal pelvis.
Major Calyx
Joins the proximal end of the ureter.
Renal Pelvis
What is the functional unit of the kidney? (Hint, each kidney contains 1.2 million)
Nephron
This makes up 85% of all nephrons, which extend partially into the medulla.
Superficial Cortical Nephrons
These have short or long loops.
Midcortical Nephrons
Lie close to and extend deep into the medulla and are important for the process of concentrating urine.
Juxtamedullary Nephrons
Three main components of the Renal Corpuscle.
- Glomerulus
- Bowman Glomerular Capsule
- Mesangial Cells
Tuff of capillaries
Glomerulus
Bowman space; Circular space between visceral and parietal epithelium
Bowman Glomerular Capsule
- Secrete mesangial matrix; lie between and support the glomerular capillaries. Some of these contracts like smooth muscle cells to regulate glomerular capillary blood flow.
- Have phagocytic properties and release inflammatory cytokines and growth factors.
Mesangial Cells
Filters selected blood components through its three layers
Glomerulus
What are the three layers of the glomerular filtration membrane?
- Inner Capillary Endothelium
- Middle Glomerular Basement Membrane (GBM)
- Outer Layer: Visceral Epithelium that forms the inner layer of the Bowman’s capsule.
- Synthesize Nitric Oxide (a vasodilator)
- Synthesize Endothelin-1 (a vasoconstrictor)
- Regulate glomerular blood flow.
Glomerular endothelial cells
- What part of the Nephron: Is composed of cells bodies called podocytes, which are foot like projections?
- Form an elaborate network of intercellular clefts called filtration slits, modular filtration.
- Supplied by the afferent arteriole and drained by the efferent arteriole.
Visceral Epithelium of the Bowman’s Capsule
What are the two components of the Juxtaglomerular Apparatus?
- Juxtaglomerular Cells
- Macula Densa
These specialized cells are located around the afferent arteriole where the afferent arteriole enters the glomerulus.
Juxtaglomerular Cells
Between the afferent and efferent arterioles of the distal convoluted tubule; sodium-sensing cells.
Macula Densa
What three things are controlled by the Juxtaglomerular Apparatus (JGA) at this site?
- Renal Blood Flow (RBF)
- Glomerular Filtration
- Renin Secretion
This is where substances are reabsorbed from the filtrate or secreted into the filtrate.
Renal Tubules
Is the only surface inside the nephron covered with microvilli?
Proximal Convoluted Tubule