Urinary System Flashcards
List the organs that make up the Urinary system
Kidney
Ureters
Urinary Bladder
Urethra
How large is an average sized kidney
11cm long
6cm wide
3cm thick
Where are the kidneys located in the body
Posterior to (behind) abdominal wall Inferior to (below) diaphragm
What is the Hillum?
Site of the kidney where renal arteries enter and veins and ureters leave
Which border is the Hillum of the kidney located?
Medial
What is the function of the Ureters?
Carry urine from Kidney to Bladder
How long are the Ureters?
25-30cm long
Which ureter is longer and why?
The right ureter because the right kidney is positioned higher than the left.
What movement occurs in the ureter and how often?
Peristalsis
4-5 times per minute
Describe the structure of a ureter.
Thick walled, narrow tube - 3mm diameter
What is the function of the Urinary bladder?
Storage of urine
How much urine can the bladder hold
Normally 230-300ml
Up to 500ml but this is painful
How many layers of tissue does the bladder have and what are they known as?
3 layers
Serous
Muscular
Inner mucous coat
What is the function of the uretha?
Pass urine to exterior
How long is the urethra in men and women?
Men - 18-20cm long
Women - 4cm long
How does the male and female urethra differ in function?
In women it serves the urinary system only
In men it is a common canal for reproductive and urinary system
List the functions of the Kidney
Body fluid Volume and osmolality Regulation
Electrolyte balance
Formation of urine through which metabolic waste products and toxins are released
Acid-base balance
Production of hormones and enzymes
What is Osmolality?
The concentration of solutes in the body fluid
What is the functional unit of the kidney known as?
Nephron
What are the component parts of the nephron in order?
Glomerulus Bowman's Capsule Proximal Convoluted Tubule Loop of Henle (Descending Limb) Loop of Henle (Ascending Limb) Distal convoluted Tubule Collecting Duct
Name the four stages of blood filtration occurring in the nephron.
Glomerular Filtration
Tubular Reabsorption
Tubular Secretion
Water Conservation
What type of arteriole enters the glomerular capsule?
Afferent
What type of arteriole leaves the glomerular capsule?
Efferent
How is kidney disease diagnosed?
By reference to Glomerular Filtration rate
What is the definition of chronic kidney disease?
GFR <60ml /min for more than 3 months
How many stages are there to kidney disease?
5
What is stage 5 kidney disease more commonly known as?
Renal failure or end stage renal disease
What are the only available treatments for stage 5 kidney disease?
Renal dialysis or transplantation
What is a normal GFR?
90-140 ml / min
Which two parts of the nephron are particularly important in urine production?
Proximal Convoluted Tubule
Loop of Henle
Distal Tubule
Collecting duct
Why do microvilli line the PCT?
Create a greater surface area for reabsorption
Why are there lots of mitochondria in the PCT?
Because solutes are reabsorbed in the PCT by the process of active transport
What are type of substances absorbed by the PCT?
Sodium
Glucose
Amino Acids
Water
How is sodium absorbed by the PCT?
Active transport
How is Glucose and Amino Acids absorbed by the PCT?
Secondary Active Transport
Water is absorbed by the PCT as a result of which transport method (form of diffusion)?
Osmosis
With regard to reabsorption of substances in the PCT, what happens when transport proteins in the plasma membrane are saturated?
Glycosuria can occur as no more glucose can be reabsorbed
Where in the nephron does counter current exchange take place?
Loop of Henle in Nephron
What substances are absorbed in the Loop of Henle and the distal tubule and collecting ducts?
Sodium
Water
How is sodium and water reabsorption regulated in the distal tubule and collecting ducts?
By hormones
Why is counter current exchange useful?
It allows the kidneys to produce concentrated urine when there is a need to conserve water
Where is potassium secreted in the nephron?
Distal Tubule and Collecting ducts
Release of what hormone increases blood volume?
Aldosterone
What effect does aldosterone have on electrolytes in the nephron?
Stimulates sodium reabsorption and potassium excretion in the distal tubule and collecting duct
Release of what hormone leads to a decrease in blood volume?
Atrial Natriuetic Peptide
What effect does Atrial Natriuetic Peptide have on Sodium?
It increases it’s excretion
What is ADH?
Anti-diuretic Hormone
What effect does an increase in ADH have on the nephrons?
The collecting ducts reabsorb more water
What effect does a decrease in ADH have on the nephrons?
It causes a decrease in water reabsorption in the collecting ducts
