Chapter 20 Flashcards
List the components of the urinary system.
Kidneys
Ureters
Urinary Bladder
Urethra
What is the ideal GFR?
Glomerular Filtration on average produces 125 ml of
fluid/minute, although most is reabsorbed.
Structural Components of Kidneys
Distinct features of those components?
-Renal Capsule : a fibrous membrane located around that renal cortex.
- Renal Cortex- forms a shell around the medulla and form renal columns.
- Renal columns the area located between renal pyramids.
- Renal Medulla - is composed of conical masses
called renal pyramids (inner portion).
-Renal Pyramids – cone shaped masses of tissue in
the renal medulla.
Ureter – muscular tubes extending from the kidneys
to the base of the urinary bladder.
Renal pelvis – superior end of ureter which is
expanded to form a funnel shape.
Major calyces (calyx)– divisions of the renal pelvis
(2-3 tubes)
Minor calyces (calyx)– divisions of major calyces
What is tubular secretion?
- The movement of substances from the blood within the peritubular capillary into the renal tubule (DCT).
- Tubular secretion accelerates the removal of certain compounds, such as hydrogen ions, andmaintains ion concentrations in the blood.
What is filtrate?
plasma pulled from blood
What are the functions of the kidney?
- maintenance of homeostasis through the regulation of composition, volume and pH of body fluids
- -Regulation of RBC formation via secretion of erythropoietin.
- Activation of Vitamin D.
- Maintenance of blood pressure (via blood volume).
- Removal of metabolic waste products from blood and body (urine).
What is the function of the urinary system?
To remove metabolic wastes from blood & remove from body
how does the kidney receives oxygenated blood?
- From renal arteries, which branch of abdominal aorta
- renal arteries enter the kidney through the
hilum and branches into the interlobar arteries,
which eventually lead to the nephron.
How does the kidney remove deoxygenated blood?
Deoxygenated blood is carried away from the
kidneys by the renal vein which joins with the
inferior vena cava.
What causes the release of renin?
The enzyme, renin, is secreted by the juxtaglomerular cells in response to:
- Drop in blood pressure – leads to decreased GHSP and GFR.
- Sympathetic stimulation
- Decrease in chloride, potassium, and/or sodium ions.
What is the functional unit of the kidney?
Nephron
What are the components of a Nephron?
Composed of a renal corpuscle and a renal tubule.
What is glomerulus?
Responsible for filtering the blood that is
received.
what are the components of JGA
Macula Densa:area where afferent & efferent arterioles & distal convulated tubule come together
Juxtagolmerular Cells-smooth muscle cells @ the afferent arteriole
What is the function of the JGA?
secrete renin
Which is involved w/ blood pressure & involved w/ glomerular filtration regulation
Blood Flow Pattern with Glomerulus
Glomerulus recieves blood from large afferent arteriole that turns into the capillaries that form the glomerulus
What Are the Steps of Urine Formation ?
Involves process of glomeruluar formation, tubular reabsorption, tubular secretion
What is Glomeruluar Filtration?
- First step of Urine Formation begins with filtrartion of plamsa by the glomerulular cappillaries
- Glomerular capillaries filter water & dissolves materials from blood (collected @ Bowman’s Capsule)
- Filtration due to force called glomerular hydrostatic pressure (GHSP)
Glomerular Hydrostatic Pressure (GHSP)
inside glomerular capillaries which is at a higher pressure than Bowman’s capsule.
- Pressure at glomerular capillaries = +60 mmHg
- Pressure at Bowman’s capsule = -18 mmHg
- Osmotic pressure at capillaries = -32mmHg
What is GFR?
The kidneys produce, on average, 125 ml of
fluid/minute, although most is reabsorbed at
the proximal convoluted tubule (PCT).
What Factors affect GFR?
Filtration Pressure
Glomerular Plasma Osmotic Pressure
Hydrostatic Pressure In The Glomerular Capsule
What is Urea?
By Product of Amino Acid Metabolism
What is Urine Acid?
By product of Nucleic Acid Metabolism
How are Urea & Urine Acid Eliminated?
Urea is passively reabsorbed by diffusion but
about 20% of urea is secreted back into the
urine.
Most uric acid is reabsorbed by active
transport and about 10% is secreted into the
renal tubule.
