Urinary Flashcards
What is the primary function of the urinary system?
Regulate body fluid, excretion, and endocrine functions
What are the 2 hormones that the urinary system secretes?
Erythropoietin and Renin
What are some waste products that are excreted through the urinary system?
Nitrogenous wastes, detoxification products, drugs and inorganic ions
Where are the kidneys located?
In the retroperitoneal area, right kidney is more cranial while the left one is more caudal
What are the structures inside of the kidney starting at the most superficial portion?
Capsule to cortex to medulla and finally to the pelvis where urine is collected
What species has a lobulated external surface on their kidneys?
Bovine and avian species
What species has a smooth external surface on their kidneys?
Canine and Equine species
What are 3 different ways the internal structures of a kidney could vary between species?
They could be homogenous (no separation), have papillae or calyx
What is the course that the ureter takes from the kidney to the bladder?
Starts at the renal pelvis, to the hilus, in the retroperitoneal fold, and then finally to the bladder passing through the intramural tunnel while forming the trigone
What is the ureter made up of?
3 layers of smooth muscle that contracts through peristalsis
What kind of tissue lines the ureter?
Transitional epithelium
What is the anatomical location of the bladder?
At the pelvic inlet, along the midline, just in front of the pubis
What suspends the bladder in place?
A middle ligament, lateral ligament and the urethra
How many layers of muscle does the bladder contain and what is it called?
The Detrusor muscle is made up of 3 layers of smooth muscles
How many sphincters does the bladder contain?
Two sphincters, an internal (smooth muscle) and an external sphincter (skeletal muscle) that close the bladder just where it meets up with the urethra
What are the 3 types of nerve supply in the bladder?
Parasympathetic, sympathetic, and somatic
What is the parasympathetic nervous system responsible for in the bladder?
Contraction of the bladder and relaxation of the internal sphincter
What is the sympathetic nervous system responsible for in the bladder?
Vasculature
What is the somatic nervous system responsible for in the bladder?
The skeletal muscle on the external sphincter (voluntary control)
Where is the urethra located in a female?
Pelvic canal
Where is the urethra located in a male?
In the prostatic, pelvic canal and penile region
Why do males have less bladder infections than females?
Males have longer urethras
Where does the urethra enter the reproductive tract?
Pelvic floor
What kind of tissue are the mucosal folds in the urethra lined with?
Transitional epithelial, but stratified squamous at the external opening
What openings into the urethra do males have?
Accessory glands, ductus deferens and the external meatus
How much of the cardiac output do the kidneys receive?
1/5th or 20% of all blood volume makes its way to the kidney
What is the pathway that the blood takes through the kidney?
Renal artery, reducing branches, afferent arterioles, glomerulus, efferent arterioles, peritubular capillaries, vasa recti, enlarging branches and then finally the renal vein
What makes up the renal corpuscle?
The glomerulus, Bowman’s capsule, and the capsular space
What is Bowman’s capsule?
Structure surrounding the glomerulus (where the afferent and efferent arterioles meet)
What kind of muscle do both the afferent and efferent arterioles contain?
Smooth muscle that allows for contraction and relaxation, so in other words, regulation of the flow of the fluid
What is in glomerular filtrate once it has entered the Bowman’s capsule?
Water, electrolytes, waste, toxin metabolites, glucose, amino acids, etc.
What are the different parts of the nephron?
The renal renal corpuscle (glomerulus, Bowman’s capsule, & capsular space), proximal convoluted tubule, loop of Henle, distal tubule, and collecting duct
What is the proximal convoluted tubule?
The first segment of a renal tubule that is responsible for reabsorption of things the body wants to keep and secretion of things it doesn’t
What is the Loop of Henle?
It is a concentration regulator that follows the proximal convoluted tube consisting of 3 segments, the descending thin, ascending thin and ascending thick portion
What is the descending thin portion of the Loop of Henle able to do?
It pulls out water, meaning that it is H2O permeable
What is the ascending thin portion of the Loop of Henle?
It is H2O impermeable, meaning water can’t enter or exit the tubule
What is the ascending thick portion of the Loop of Henle?
The final portion of the Loop of Henle that is impermeable to water but can absorb electrolytes
What is the distal convoluted tubule?
Follows after the Loop of Henle and it functions more in secretion than reabsorption
What is the difference between the early and late distal convoluted tubule?
The early DCT reabsorbs electrolytes, while the late DCT absorbs NaCl and bicarbonate. the late DCT also secretes electrolytes to regulate pH.
What are two of the main nitrogenous waste products that the kidneys normally eliminate through secretion?
urea and creatinine (both byproducts of protein metabolism)
What is the collecting duct?
Receives fluid from the DCTs of several nephrons as it passes back into the medulla
Filtration control in the kidney is autoregulated, how does it achieve this?
Through the juxtaglomerular apparatus
What is the juxtaglomerular apparatus?
A system that regulates the rate of filtrate formation and systemic blood pressure, reacting to the concentration levels and acting accordingly. This will tell the body to retain/release fluid.
What hormone is responsible for water control in the kidney?
Antidiuretic hormone
What are some things that can trigger antidiuretic to be activated?
Increase in NaCl, decrease in either blood pressure or blood volume
What is the end product of the kidney at work?
Urine with a variable concentration of H2O, Na+, Cl-, H+, HCO3, Urea, creatinine, etc.
