Week Eight: Urinary System Flashcards
What is the function of the kidneys?
Maintain homeostasis
How do kidneys maintain homeostasis?
Through filtration, reabsorption, secretion
Fluid balance regulation
Acid-base balance regulation
Production of hormones
What cavity are the kidneys found in?
Retroperitoneal
In most domestic animals, right kidney is more ______ than the left
Cranial
Where is the hilus?
Indented area on medial side of the kidney (where ureters, nerves, blood, and lymph vessels enter and leave the kidney)
What is the renal pelvis?
Funnel-shaped area inside the hilus
Forms beginning of ureter
What type of cell is the renal pelvis lined with?
Transitional epithelium
What is the renal cortex?
Outer portion of the kidney
What is the renal medulla?
Inner portion around the renal pelvis
What is the calyx?
Cuplike extension of the renal pelvis where the medullary pyramids fit
Act as funnels to direct fluid into renal pelvis
What is a nephron?
Basic function unit of kidneys
What does a nephron consist of?
Renal corpuscle, proximal convoluted tubule, loop of Henle, and distal convoluted tubule
Where is the renal corpuscle located?
In renal cortex
What is the function of the renal corpuscle?
Filters blood in first stage of urine production
What is glomerular filtrate?
Fluid filtered out of blood
What are glomerulus?
“tuft” of capillaries
What is the renal corpuscle composed of?
Glomerulus and is surrounded by Bowman’s capsule
What is the proximal convoluted tubule? (PCT)
Continuation of capsular space of Bowman’s capsule
What type of cell is PCT lined with?
Cuboidal epithelial cells
What type of cell is the descending part of the Loop of Henle composed of?
Epithelial cells
At the bottom of the loop of Henle, the epithelial cells flatten to what type of cell?
Simple squamous epithelial cells
Where does the distal convoluted tubule (DCT) empty into?
Collecting ducts
Where does the renal artery enter the kidney at?
The hilus
The renal artery divides into smaller arteries and arterioles and ends as what?
Glomerulas
Afferent glomerular arterioles carry blood into…
Glomerular capillaries of renal corpuscle
Glomerular capillaries filter some of the plasma out of blood and put it in the capsular space of….
Bowman’s capsule
Efferent glomerular arterioles divide to form what?
Peritubular capillaries
Where does oxygen transfer take place in the urinary system?
Peritubular capillaries
Peritubular capillaries converge to form venules, then larger veins, and finally the…
Renal vein
The renal vein leaves the kidneys at the _______ and joins the ______ portion of the caudal vena cava
Hilus; abdominal
True or False
Glomerular capillaries contain fenestrations large enough to allow blood cells or large proteins to pass through
False, not large enough
What is Glomerular filtration rate (GFR)
How fast plasma is filtered through glomerulus
Glucose and amino acids attach to ____ carrier protein and follow sodium into the cell by passive transport
The same carrier
During sodium reabsorption, how is sodium moved into the PCT?
Sodium attaches to carrier protein that moves it into the PCT
During sodium reabsorption, sodium is pumped out of the cell into _____ _____, where it moves into peritubular capillaries
Interstitial fluid
Where are sodium ions reabsorbed?
Loop of Henle and DCT
Where do potassium and calcium reabsorption take place?
In the PCT, ascending loop of Henle, and DCT
Calcium moves from the filtrate under the influence of what three things?
Vitamin D, parathyroid hormone (PTH), and calcitonin
Where is magnesium reabsorbed from?
PCT, ascending loop of Hnele, and collecting duct
Where does secretion in the urinary system primarily occur?
In the DCT
What three things are eliminated by secretion in the urinary system?
Hydrogen, potassium, and ammonia
What is urine volume regulation determined by?
Amount of water contained in the tubular filtrate when it reaches renal pelvis
What is urine volume regulation controlled by?
Actions of ADH and aldosterone
Aldosterone _____ reabsorption of sodium
Increase or decrease
Increases
Ureters leave the kidney at the…
Hilus
What kind of muscle is found in the ureters?
Smooth muscle
What type of cell is the urinary bladder lined with?
Transitional epithelium
What is micturition or uresis?
Expulsion of urine from the urinary bladder into the urethra
A spinal reflex returns a motor impulse to bladder muscles causing them to…
Contract
What gives the sensation of having to urinate?
Contraction of the bladder
What carries urine from the urinary bladder to the external environment?
Urethra
