The Urinary System ConnectHW

false statements about the kidneys

-both kidneys are found within the peritoneal cavity -the left kidney is located more inferior than the right kidney -the kidnyes are located completely within the level of the thoracic spine -on average, each kidney weights about 1 kg -the kidneys are superior to the adrenal glands

negative feedback control of GFR

-high GFR -increased NaCL load in nephron loop -macula densa secretes ATP -mesangial cells metabolize ATP to adenosine -adenosine stimulates granular cells -afferent arteriole constricts -reduced GFR

true statements about the kidneys

-the kidneys each have one ureter -the kidneys are retroperitoneal -the concavity of the kidney is called the hilus -the kidneys are bound to the abdominal wall by the renal fascia -a midsagittal section would not show either kidney

Renin Angiotension Aldosterone Mechanism

1.) A decrease in blood pressure is sensed by the macula densa, resulting in stimulation of granular cells. 2.) The granular cells respond by secreting renin into the plasma, which eventually encounters angiotensinogen from the liver. 3.) Angiotensinogen is converted to angiotensin I as a result of the action of the enzyme renin. 4.) Now 10 amino acids long, angiotensin I continues to circulate until being acted upon by ACE. 5.) ACE from the lungs finalizes the conversion to angiotensin II. 6.) Now in an active form, the hormone, angiotensin II binds to target cells in three distinct areas of the body. 7.) The resulting actions of angiotensin II cause the release of ADH from the hypothalamus, aldosterone from the renal cortex, and widespread vasoconstriction.

would decrease urine volume

A. increase permeability of water in collecting duct B. overexertion of aquaporins C. working outside without water access

would increase urine volume

A. taking a diuretic B. developing diabetes C. decreasing cAMP levels in collecting duct cells D. drinking large volume of water when you've rested all day

decreases filtration

- increase in capsular pressure - increase in plasma protein concentration - obstruction in the proximal tubule

the hormone _________ acts in this part of the nephron and has a big impact on Na+ and K+ levels in the filtrate

aldosterone

When blood pressure drops, renin is released into the blood, resulting in an increase in the hormone ----- , which acts to decrease GFR while simultaneously raising blood pressure.

angiotensin II

Overconsumption of alcohol can cause the hypothalamus to sense that the blood is too dilute, resulting in a decrease in the production of _________ This reduces the reabsorption of water, leading to dehydration.

antidiuretic hormone

heading up the _______ limb, urea is secreted

ascending

When the level of the hormone _______________ increases, a person will experience an increase in Na⁺ excretion in their urine.

atrial natriuretic peptide

negatively charged proteoglycans found in the _____ prevent most proteins in the blood from exiting the glomerular capillaries

basement membrane

what force opposes glomerular filtration

capsular hydrostatic pressure (HPc) and blood colloid osmotic pressure (OPg)

antidieuretic hormone

causes water to reenter the blood stream via the collecting duct

Angiotensin II triggers the __________________________ of the intraglomerular mesangial cells which results in a(an) _______________________________ of the filtration surface area.

contraction; decrease

If both the glomerular and capsular hydrostatic pressures remain unchanged, an increase in the blood colloid osmotic pressure results in a(n) _____________ in the net filtration pressure.

decrease

increase in ADH

decrease urine volume

increase in aldosterone

decrease urine volume

Proteinuria occurs when the filtration membrane becomes leaky, allowing proteins to cross. This impacts the blood colloid osmotic pressure by ____________________ the osmolarity gradient between the blood and filtrate, thereby ________________ the strength of this pressure.

decreasing; reducing

once in the nephron loop, the _______ limn reabsorbs water

descending

small window like openings in the capillary endothelium, called ______, are too small to allow cells to leave the glomerulus

fenestrae

a kidney infection or injury that results in damage to the ______ may result in proteinuria

filtration membrane

the volume of blood that enters the afferent arteriole is not equal to the volume of blood that travels through the efferent arteriole due to the process termed

glomerular filtration

conversely, there is a noticeable reabsorption of ______, amino acids, urea, and vitamins in the same region of the tubule

glucose

the afferent arteriole contains cells called ______ that secrete the enzyme renin

granular cells

parathyroid hormone

increaes phosphate levels in urine

an increase in the NFP would result in a _____ in the GFR

increase

increase filtration

increase in blood pressure and constriction of the efferent arteriole

increase in ANP

increase urine volume

increase in blood pressure

increase urine volume

Inhibiting the sodium-glucose symport SGLT2 is expected to cause a(n) __________________________ in the osmolarity of the tubular filtrate, and would thus _____________________ the risk of dehydration.

increase; increase

would promote increase in blood pressure

increased release of renin, vasoconstriction, increased production of angiotension II, increased activity of ACE, increasing levels of aldosterone, increased activation of the thirst mechanism

ADH

increases water permeability of the collecting duct; increases reabsorption of water via the collecting duct

natriuretic peptides

inhibit NaCl reabsorption by the collecting duct

natriuertic peptides

inhibits ADH secretion, increaes hydrostatic pressure in the golumerular capillaries, inhibits NaCl reabsorption via the collecting duct

the three components of the __________ are granular cells, the macula densa, and the mesangial cells

juxtaglomerular apparatus

epithelial cells found where the distal tubule passes between the afferent and efferent arterioles are called the ______

macula densa

The afferent arteriole reflexively contracts in response to a rise in blood pressure, thus preventing a rise in GFR. This form of regulation is called the

myogenic mechanism

pathway of urine formation to urine output

nephron collecting tubule collecting duct papillary duct minor calyx major calyx renal pelvis ureters bladder urethra

a person who experiences higher than normal levels of phosphate in their blood and higher than normal levels of Ca2+ in their urine, probably suffer from a defieciency in the production of _____

parathyroid hormone

filtration is a _______ process that depends on a _______ gradient

passive; pressure

filtration slits are formed by

podocytes

which of the following substances utilizes paracellular transport in order to cross the basolateral membrane of the tubule cell during the process of reabsorption?

potassium

Inactivating the sodium-glucose symport SGLT2 inhibits the reabsorption of glucose by

preventing glucose from entering the tubular cells

the cell type in the distal tubule and collecting duct that is responsible for Na+ and water reabsorption is the ______

principal cell

tubular ______ and secretion occurs with varying solutes in the renal tubules

reabsorption

When there is a drop in blood pressure, the juxtaglomerular cells respond by secreting which of the following?

renin

which of the following describes the location of the kidneys?

retroperitoneal at the level of T12 to L3

aldosterone characteristics

stimulated by angiotension II and last step of renin-angiotensin mechanism

aldosterone

stimulates sodium ion retention

renin is released in response to ______ stimulation

sympathetic

ACE inhibitors are prescribed to control blood pressure; these drugs work by reducing

the conversion of angiotension I to angiotension II

glomerulosclerosis results in a ________ of the basement membrane

thickening

Tubular reabsorption and tubular secretion differ in that __________________________.

tubular secretion adds materials to the tubular filtrate while tubular reabsorption removes materials from the tubular filtrate

the process whereby the flow of filtrate through the distal tubule results in changes in GFR is termed

tubuloglomerular feedback

nitrogenous wastes of the human body

uric acid, urea, creatinine

would promote a decrease in blood pressure

vasodilation, declining levels of ADH, decreased sodium reabsorption

in the ____ there is secretion of urea, H+, creatine, and uric acid

PCT

the flow of fluid through the renal tubules

1.) The glomerular capsule leads into the proximal convoluted tubule, the longest and most coiled of the four regions of the renal tubule. 2.) From there, the filtrate flows into the descending limb of the nephron loop, the first part of the U-shaped portion of the tubule found mostly in the medulla. 3.) Next, the flitrate makes a 180 degree turn into the ascending limb, returning to the renal cortex. 4.) The filtrate is funnelled into the distal convoluted tubule, the end of the nephron. 5.) The collecting duct receives the filtrate from the DCTs of several nephrons and funnels it toward the renal pyramid.

In the DCT, ____________ can be reabsorbed and secreted heading into the collecting duct.

K+

An increase in the rate of filtrate flow through the distal tubule results in contraction of the _____ and a decrease in GFR.

afferent arteriole

which blood vessel carries blood into a gloumerulus

afferent arteriole

When systemic blood pressure decreases, the result is that the ___________ arterioles change diameter by undergoing ______________.

afferent; vasodilation