urinary Flashcards
the urinary system is involved in the regulation of what?
blood glucose levels
electrolyte balance
pH of blood
how is the kidneys involved in maintaining normal body fluid composition and pH?
by adjusting composition of the urine produced
how is the kidneys involved in the regulation of red blood cell production.
produces the hormone erythropoietin
how is the kidneys involved in blood-pressure regulation?
- altering the volume of urine produced
- producing the enzyme renin, which catalyzes the production of angiotensin I.
how is the kidneys involved in the absorption of calcium from the digestive tract?
activate vitamin D
Describe the composition of glomerular filtrate
Like plasma but lacking larger protein molecules
fill in the blank
Vasoconstriction of the afferent arteriole and/or vasodilation of the efferent arteriole will cause a(n) __________ in glomerular filtration rate (GFR).
decrease
Why is there a greater amount of filtration occurring at glomeruli compared to other capillary beds of the body?
Glomeruli have a higher hydrostatic pressure.
what substances are reabsorbed from filtrate
water
glucose
HCO3-
Na+
amino acids
what substances are secreted into filtrate
NH4+
H+
drugs
fill in the blank
Water reabsorption from the proximal convoluted tubule is closely linked to the active reabsorption of __________.
sodium ions
When the urinary bladder becomes stretched, there is an increase in the frequency of action potentials traveling from where to where?
The urinary bladder to the sacral region of the spinal cord
In response to activation of the micturition reflex, __________ stimulate the smooth muscle of the urinary bladder to contract.
parasympathetic neurons
When urination is desired, decreased action potentials along which nerve pathway cause relaxation of the external urinary (urethral) sphincter?
Somatic motor neurons from the spinal cord
In order for urination to occur, the _______ must relax, and the ________ must contract.
- urethral sphincters
- detrusor muscle
which part of the nephron filters fluids and solutes from plasma
glomerulus
which part of the nephron receives plasma filtrate
glomerular capsule
which part of the nephron reabsorbs nutrients, glucose, various ions, and water
Proximal convoluted tubule
which part of the nephron reabsorbs of only water
Descending limb of nephron loop
which part of the nephron does selective reabsorption of sodium, potassium, and chloride ions
Ascending limb of nephron loop
which part of the nephron reabsorbs sodium and water and secretes of hydrogen and potassium ions
distal convoluted tubule
what’s the definition of homeostasis
the maintenance of a stable internal environment. The function of the kidneys is important in maintaining the internal environment.
As water volume in the blood decreases and the osmolarity increases, the hormone _______ is released, causing the kidneys to retain water.
ADH
what is the role of aldosterone when sodium levels are decreased
It causes an increase in sodium reabsorption by the distal convoluted tubule and collecting duct.
As blood pH decreases, the secretion of _______ by the renal tubules increases, producing a more acidic urine.
hydrogen ions
the kidneys are able to handle each component independently. Those that are too abundant in the blood are _______, and those whose levels are dropping are _______
- excreted
- reabsorbed
The descending limb of the nephron loop is permeable to ________ which will _______ the renal tubule.
- water
- leave
The ascending limb of the nephron loop is permeable to ______ which will _______ the renal tubule.
- salts
- leave
What are the components of a nephron?
renal corpuscle
renal tubule
is the external urethral sphincter under voluntary or involuntary control
voluntary
The major regions of the kidney are the outer region called the __________ and the inner region called the __________.
cortex
medulla
Water and sodium ions are reabsorbed from the proximal tubule in a process that results in a(n) __________ in tubular fluid volume that is __________ to plasma.
decrease
isotonic
Stimulation by __________ motor impulses causes the detrusor muscle to contract rhythmically.
parasympathetic
what does GFR depend on
pressure in the afferent arterioles
Which of the following is NOT a stage of urine formation?
Glomerular filtration
Tubular secretion
Glomerular secretion
Tubular reabsorption
Glomerular secretion
Lasix is a diuretic that blocks the reabsorption of sodium in the ascending limb of the nephron loop. What would be the result of giving lasix?
Increased urine output
What determines the composition of urine?
The ratio of water and solutes eliminated to maintain internal environment
An increase in the amount of protein in the diet would lead to an increased concentration of which of the following in the urine?
urea
When there is an excess of water in body fluid, ADH secretion __________.
decreases
structures and characteristics of the renal medulla
medulla
nephron loops
collecting ducts
site of reabsorption
site of secretion
structures and characteristics of the renal cortex
cortex
renal corpuscle
PCT
DCT
collecting ducts
nephron loops
site of filtration
site of reabsorption
site of secretion
