Module 16 - The Urinary System Flashcards
Where do the kidneys get their blood supply?
the renal arteries
Kidneys are intra or retroperitoneal?
retroperitoneal
What is a horseshoe kidney?
inferior aspects of the left and right kidneys fuse as they try to ascend into the abdominal cavity (the inferior mesenteric artery extends anteriorly so it acts as a hook)
What is a pelvic kidney?
when the kidney fails to migrate superiorly
What are the structural and functional units of the kidney?
nephrons
What is the difference between cortical and juxtamedullary nephrons?
-cortical nephrons are most common (85%), primarily in the cortex, and have a short nephron loop
-the juxtamedullary are less common (15%), have a long nephron loops that extend deep into the medulla and have a greater role in producing concentrated urine
What is the first capillary bed the afferent arteriole supplies?
the glomerulus which exists in the renal corpuscle for filtration (before exchange with cells)
What does the glomerulus capillary bed supply?
the efferent arteriole which exits and continues to feed the rest of the nephron
What is the second capillary bed the efferent arteriole supplies?
the pertibular capillaries or vasa recta which removes waste products
How is filtration regulated?
Filtration is regulated by fenestrations in capillary endothelial cells, podocytes with filtration slits, membrane charge, and the basement membrane between capillary cells
What is in the filtrate?
Filtrate that does not contain cells or large proteins and has a slight predominance of positively charged substances
What is the pathway of Urine?
After kidneys filter and reabsorb → collecting tubules → collecting ducts → minor + major calyx → renal pelvis → ureters → bladder → urethra
The ______ urethral sphincter contracts to store urine under _________ stimulation, preventing leakage.
internal; sympathetic
The detrusor muscle ______ to store urine to allow bladder expansion
relaxes
During urination, the _______ sphincter relaxes _______, while the detrusor _______ under _____________ control to generate pressure and expel urine.
externa, voluntarily; contracts, parasympathetic
What are the cups that hold drip?
the minor and major calyx
Blood pressure is high in what capillary that feeds the nephron? What does this do?
the glomerulus; forces filtrare out of blood into capsule
Which arteriole is larger - the afferent or efferent?
the afferent
The fenestrated endothelium of the glomerulus only allows 3nm molecules to pass. What are some examples?
water, amino acids, wastes, glucose
The proximal convoluted tubule is lined by what kind of epithelium and functions to do what?
simple cuboidal with tall microvilli; cells reabsorb almost all nutrients, ions, vitamins, water, and plasma proteins
What occurs in the nephron loop (loop of henle)?
it projects into the medulla and contains a descending limn which is water permeable and a ascending limb which is solute permeable. It allows filtrate to be returned to blood via the peritubular capillaries and/or vacta rescta
The distal convoluted tubule is lined by what kind of epithelium and functions to do what?
it is composed of simple cuboidal with sparse microvilli; it is specialized for selective secretion and reabsorption of ions
What are the last structures that modify the tubular fluid ad have a key role in conserving body fluid?
the collecting tubules and ducts
What is the urine path out of the kidney?
renal papilla → minor calyces → major calyces → renal pelvis → ureter
What is the first part of the urinary system to be lined with transitional epithelium?
the renal pelvis
The function of the ureters is to:
carry urine from the kidneys to the urinary bladder (propel urine to the bladder)
Renal calculi are:
kidney stones
At the proximal end of the urethra, the epithelium is ________ and near the distal end it is _________/
transitional; stratified squamous
During filling, _________ nerves contract the internal urethral sphincter and relax detrusor. ____________ nerves contract the external urethral sphincter
sympathetic; somatic (puedal)
The parietal layer of bowman’s capsule is lined with:
simple sqamous epithelium
What are the key differences between the male and female urethras?
female: only expels urine and is shorter/more prone to infection
male: expels semen and urine and is longer
