Chapter 24: Urinary System

Normally urine is composed of which of the following: () Ions () Formed elements () Glucose () Waste products () Water

(x) Ions () Formed elements () Glucose (x) Waste products (x) Water

4 Steps of Micturition Reflex:

1. When volume of urinary bladder reaches 200-300mL, the bladder becomes distended, and baroreceptors in the bladder wall are activated 2. baroreceptors send nerve signals through visceral sensory neurons to stimulate micturition center within pons 3. micturition center alters nerve signals propagated down spinal cord through parasympathetic pelvic splanchnic nerves 4. parasympathetic stimulation causes smooth muscle cells composing detrusor muscle to contract and internal sphincter muscle to relax. in infants, urination occurs at this point because they lack voluntary control of external urethral sphincter

Condition of extreme dehydration result in subsequent high concentration of __________ in the blood.

ADH

When the urine is extremely dilute and appears a light pale color, a decrease in the release of _________ is evident.

ADH

Which type of nephron has relatively short nephron loops that extend into the medulla?

Cortical

_______ is only secreted.

Creatinine

Type B intercalated cells secrete _______ and reabsorb _________.

HCO3-, H+

Which type of nephron has a renal corpuscle that lies close to the corticomedullary junction with a long nephron loop that extends deep into the medulla?

Juxtamedullary

T/F: Filtration occurs in the renal corpuscle.

True

T/F: One of the kidneys' functions is the regulation of the body's acid-base balance.

True

________ cells reabsorb potassium (K+) continuously in the collecting tubule.

Type A intercalated

In the urinary system there are (____a____) kidney(s), (____b____) ureter(s), (____c____) urinary bladder(s), and (____d____) urethra(s).

a- 2 b- 2 c- 1 d- 1

One component of the juxtaglomerular apparatus is which of the following? a. granular cells b. renal papilla c. efferent arteriole

a. granular cells

Match the organ of the urinary system with its function: a. Reservoir for urine until micturition (urination) occurs b. Transports urine from kidney to urinary bladder via peristalsis c. transports urine from urinary bladder to outside the body d. filters blood and processes filtrate into tubular fluid, then urine

a. urinary bladder b. ureter c. urethra d. kidney

One component of the juxtaglomerular apparatus is which of the following? a. collecting tubule b. macula densa c. capsular space

b. macula densa

In the regulation of pH of both urine and blood, bicarbonate ions move freely across the filtration membrane and only small amounts of hydrogen ions are filtered, with most remaining in the blood. The filtered _______ must be reabsorbed to ensure blood pH does not become to acidic.

bicarbonate

The pH or urine, and consequently, the pH of blood, are regulated in the _________ .

collecting tubules

When a kidney is sectioned along a coronal plane, there is an outer renal ______ and an inner renal ______.

cortex; medulla

The epithelial cells of the collecting tubules are ________ but are __________ cell in the collecting ducts near the renal papilla.

cuboidal, columnar

Parathyroid hormone, PTH, is released from the parathyroid gland in response to __________.

decreased blood Ca2+

Each nephron loop has two limbs, a(n) ________ limb that extends from the cortex to the medulla and a(n) ___________ limb that returns blood back into the renal cortex.

descending, ascending

Blood vessels, nerves, and the renal pelvis enter/exit the kidney at the:

hilum

At the neck of the urinary bladder is the _____________ urethral sphincter.

internal

There are two types of nephrons, cortical nephrons and ________ nephrons.

juxtamedullary

The functional filtration unit of the kidney is the:

nephron

The most powerful stimulant to cause release of aldosterone from the adrenal cortex is an elevated ___________ blood level.

potassium (K+)

Approximately 60% of the Ca2+ in the blood becomes part of the filtrate while the remainder is bound to _______ in the blood and is prevented from being filtered.

protein

In the _______, 60-80% of the potassium (K+) in the tubular fluid is reabsorbed.

proximal convoluted tubule (PCT)

Substances are _______ when they move from the tubular fluid back into the blood.

reabsorbed

The two components of a nephron are the:

renal corpuscle and renal tubule

Collecting ducts and collecting tubules project through the _________ toward the ____________.

renal medulla, renal papilla

The major calyces merge to form a single, funnel-shaped:

renal pelvis

The granular cells of the JGA, synthesize, store, and release ____________.

renin

The distal convoluted tubule originates in the renal cortex at the end of the __________ .

thick ascending limb of the nephron loop

Approximately 10-20% of the potassium (K+) in tubular fluid is reabsorbed in the ________.

thick segment nephron loop ascending limb

When empty, the urinary bladder exhibits an __________ shape.

upside-down pyramid

The urinary tract consists of ___________, urinary bladder, and urethra.

ureters

The _________ is a fibromuscular tube that conducts urine outside of the body.

urethra

__________ _______ is the nitrogenous waste produced from nucleic acid breakdown.

uric acid

The body's main nitrogenous waste products are:

uric acid, creatinine, urea

The ________ _______ is an expandable, muscular sac that can store as much as 1L of urine.

urinary bladder