Urinary System Flashcards
a system that rids the body of waste products.
Urinary System
Functions of the kidney:
- filters blood plasma
- separate wastes from useful chemicals
- returns useful substances to the blood
- eliminates wastes
- regulate blood volume and pressure by
eliminating or conserving water
from amino acids in extreme starvation
Gluconeogenesis
any substance that is useless to the body or present
in excess of the body’s needs
Waste
waste substance produced by the body
Metabolic waste
Product of nucleic acid catabolism
Uric acid
Product of creatine phosphate catabolism
Creatinine
expression of the level of nitrogenous waste in the blood
Blood urea nitrogen (BUN)
elevated BUN
Azotemia
syndrome of diarrhea, vomiting, dyspnea, and cardiac arrhythmia stemming from the toxicity of nitrogenous waste
Uremia
treatment of Uremia:
hemodialysis or organ transplant
separation of wastes from the body fluids and the elimination of them
Excretion
Four body systems carry out excretion:
- Respiratory system
- Integumentary system
- Digestive system
- Urinary system
The lateral surface is _______, and the medial is concave with a slit called the _______.
convex
hilum
Three protective connective tissue coverings:
- Renal fascia - immediately deep to the parietal peritoneum
- Perirenal fat capsule - cushions kidney and holds it into place
- Fibrous capsule - encloses kidney protecting it from trauma and infection
glandular tissue that forms urine
Renal parenchyma
contains blood and lymphatic vessels, nerves, and urine-collecting structures
Renal sinus
Two zones of renal parenchyma:
- Outer renal cortex
- Inner renal medulla
extensions of the cortex that project inward toward sinus
Renal columns
6 to 10 with broad base facing cortex and renal
papilla facing sinus
Renal pyramids
cup that nestles the papilla of each pyramid; collects it urine
Minor calyx
formed by convergence of two or three minor calyces
Major calyces
formed by convergence of two or three major calyces
Renal pelvis
a tubular continuation of the pelvis that drains the urine down to the urinary bladder
Ureter
Renal artery divides into segmental arteries that give rise to:
- Interlobar arteries: up renal columns, between pyramids
- Arcuate arteries: over pyramids
- Interlobular arteries: up into the cortex
-
Branch into afferent arterioles: each supplying
nephron - Leads to a ball of capillaries— glomerulus
empties into inferior vena cava
Renal vein
Each nephrons are composed of two principal parts
– Renal corpuscle: filters the blood plasma
– Renal tubule: long coiled tube that converts the filtrate
a layer of Bowman capsule that is simple squamous
epithelium
Parietal (outer) layer
a layer of Bowman capsule that consists of elaborate cells called podocytes that wrap around the capillaries of the glomerulus
Visceral (inner) layer
separates the two layers of the Bowman capsule
Capsular space
the side of the corpuscle where the afferent arterial enters the corpuscle and the efferent arteriole leaves
Vascular pole
the opposite side of the corpuscle where the renal tubule begins
Urinary pole
a duct that leads away from the glomerular capsule and ends at the tip of the medullary pyramid
Renal (uriniferous) tubule
arises from glomerular capsule
Proximal convoluted tubule (PCT)
long U-shaped portion of renal tubule
Nephron loop (loop of Henle)
begins shortly after the ascending limb reenters the cortex
Distal convoluted tubule (DCT)
receives fluid from the DCTs of several nephrons as it passes back into the medulla
Collecting duct
formed by merger of several collecting ducts
Papillary duct
the flow of fluid from the point where the glomerular filtrate is formed to the point where urine leaves the body:
glomerular capsule → proximal convoluted tubule → nephron loop → distal convoluted tubule → collecting duct → papillary duct → minor calyx → major calyx → renal pelvis → ureter → urinary bladder → urethra
85% of all nephrons
Cortical nephrons
15% of all nephrons
Juxtamedullary nephrons
nerves and ganglia wrapped around each renal artery
Renal plexus
