Urinary System Flashcards
What are the components of the urinary system?
Kidneys
Ureters-conduct urine from kidneys to bladder
Urinary bladder-distensible reservoir for urine
Urethra-fibromuscular tube conveys urine from bladder to exterior
What are the functions of the kidneys?
Remove metabolic waste
Conserve body fluid, produce urine
Regulate pH and blood pressure
Endocrine organ that produce erythropoietin and renin
What are the parts of the kidney macrostructure?
Capsule formed by DICT made by collagen fibers, fibroblasts and myofibroblasts
Renal calyces consisting of minor and major calyces lined with transitional epithelium,no more change in urine
Renal pelvis larfer reservoir open into ureter
Hilum
What are the 2 parts of the kidney substance?
Cortex-external part- in fresh specimen more red than medulla
Medulla- Internal part
What are the parts of the kidney cortex?
Renal corpuscles only found in cortex
Renal tubules
Renal columns found between pyramids of medulla
What are the components of the renal tubules?
Cortical labyrinth made of convoluted tubules
Medullary rays formed by straight tubules and collecting dusts
What are the components of the medulla?
Pyramids (8-12) formed by the renal tubules
Papilla-tip of the pyramid formed by the perforated plate called the area cribosa where collecting ducts empty into minor calyces
What are the divisions of the medulla?
Outer medulla made of thick and thin tubules. Consists of 2 parts:
The outer stripe -only thick tubules present
The inner stripe- both thick and thin tubules present
Inner medulla made of only thin tubules
What is the nephron?
Functional unit of kidney.Consists of:
renal corpuscles
renal tubules with unclear lateral sides
Each nephron is unbranched
Several nephrons empty into a collecting tubule via connecting tubule
What are the characteristics of the renal corpuscle?
Spherical structure whose major function is filtration of blood
Consists of glomerulus surrounded by Bowman’s capsule
What are the characteristics of the Bowman’s capsule?
2 layers providing entry and exit for blood vessels and renal tubules
Parietal layer is a simple squamous epithelium
Visceral layer is formed by modified epithelial cells with processes called podocytes
Between the 2 layers is the urinary space
What are the processes of the podocytes?
Primary processes-larger
Secondary processes or pedicels envelop glomerular capillaries by interdigitating and leaving small gaps called filtration slits
Slit diaphragm is a negatively charged barrier located at the base of the filtration slits and formed by component of glycocalyx of adjacent cells
What is the vascular pole?
Area of Bowman’s capsule where blood vessels enter and exit corpuscle
What is the urinary pole?
Area of Bowman’s capsule where proximal convolute tubule draining urinary space originates
What are the characteristics of the glomerulus?
Cluster of fenestrated capillaries without diaphragm and a single basal lamina
Mesangial cells located at the end of capillaries
What are the functions of the mesangial cells?
Control glomerular flow
Possess angiotensin 2 receptors causing a reduction in blood flow
Structural support for glomerulus
Phagocytose of residue and protein trapped on basal lamina