Chapter 23 Urinary System
The motor fibers of the renal plexus are branches of the ___ nervous system
sympathetic
In the kidney, the process by which fluid and solutes from the tubular fluid are moved to the blood is called tubular
reabsorption
The kidneys play a major role in the regulation of ____ and ____
acid-base balance
electrolytes
List, in order, the structures through which a drop of urine will flow after it drains from a renal papilla
minor calyx
major calyx
renal pelvis
ureter
The ____ of the kidney is the inner layer, while the ____ is the layer surrounding it
medulla; cortex
The renal pelvis funnels urine into the tube called the
ureter
List the functions of the kidneys
regulations of electrolyte balance
site of calcitriol activation
filtering blood to remove the metabolic waste
The glomerulus is a bed of capillaries surrounded by a
glomerular capsule
The functional unit of the kidney is called the
nephron
List solutes that are reabsorbed from the nephron loop
sodium
potassium
chlorine
The renal medulla is comprised of
renal pyramids and renal columns
The process by which water and some solutes in the blood plasma pass from the glomerular capillaries into the capsular space is called the glomerular
filtration
List some variables that affect the glomerular filtration rate
permeability of filtration membrane
surface area available for filtration
List in order, from the blood side to the capsular space, the structures through which any filtered substance must pass
fenestrated endothelium of the capillary
basement membrane
filtration slits
Activation of the renin-angiotensin mechanism initiates changes that will result in an _____ in blood pressure
increase
Urine is conveyed out of the body by a tube called the
urethra
The ____ can be described as a muscular sac on the floor of the pelvic cavity, inferior to the peritoneum and posterior to the pubic symhpysis
bladder
Nephrons classified as ____ nephrons have long nephron loops that extend deep into the medulla
juxtamedullary
The _____ _____ carries blood from the glomerulus into the peituibular capillaries
efferent arteriole
Filtration pressure at a glomerulus is determined by the balance of ____ pressure and ____ pressure
hydrostatic
colloid osmotic
The process of separating wastes from bodily fluids and elimination them from the body is called
excretion
Name the plasma protein that is converted by renin to angiotensin I
angiotensinogen
Renal clearance is the net effect of
glomerular filtration of waste
amount added by tubular secretion
amount removed by tubular reabsorption
List the order of arteries carrying blood from the renal artery into the renal cortex
segmental arteries
interlobar arteries
arcuate arteries
cortical radiate arteries
A nephron consists of ______ and ______
renal corpuscle and renal tubule
Clearing aspirin, penicillin, and other drugs from the blood stream via the kidneys are examples of tubular
secretion
Describe the location of the kidneys
retroperitoneal at the level of T12 to L3
Small molecules can pass freely through the filtration membrane into the capsular space. Those molecules that have passed through the filtration membrane include
electrolytes, water, glucose
The fluid in the glomerular capsule is formed by filtration at the glomerulus. This fluid is called _____
filtrate
The tubuloglomerular feedback mechanism of GFR regulation relies on the monitoring of tubular fluid by a renal structure called the _____ _____
juxtaglomerular apparatus
The amount of water reabsorption can be altered, allowing the production of either a concentrated or dilute urine. This is the role of the ____ ____ of the renal tubules
collecting duct
The primary function of the nephron loop is to generate a medullary ECF osmotic gradient that allows the ____ of urine
concentration
Tubular secretion is important for waste removal. Some of the substance that are secreted include
bile acids, ammonia, urea
From deepest to most superficial, list the layers of connective tissue that surround the kidney
fibrous capsule
perirenal fat capsule
renal fascia
Name the length of tube that includes the proximal convoluted tubule, nephron loop, distal convoluted tubule, and collecting duct
renal tubule
The kidneys regulate blood volume and blood pressure by
regulating water output
A chemical that increases urine volume is called a _____
diuretic
List some hormones that regulate the amount of water and salts that is reabsorbed by the distal convoluted tubule and collecting duct
aldosterone
antidiuretic hormone
atrial natriuretic peptide
List renal tubular segments that are influenced by aldosterone
ascending limb of nephron loop
collecting duct
distal convoluted tubule
Name the hormone that makes the collecting duct more permeable to water so water reenters the tissue fluid and blood rather than being lost in the urine
ADH
The blunt tips of the renal pyramids, from which urine is collected into the calyces, are called renal
papilla
Describe the benefit of renal autoregulation
GFR held steady regardless of changes in mean arterial pressure
List the components of a renal corpuscle
glomerular capsule
glomerulus
Describe collecting ducts
carry fluid from multiple nephrons to renal papillae
The kidneys produce _____, a hormone that stimulates the production of red blood cells
erythropoietin
Define transport maximum
the upper limit of amount of solute that can be reabsorbed
The detrusor muscle is thickend near the urethra to from an internal urethral sphincter which compresses the urethra and retains urine in the bladder. This sphincter is composed of _____ muscle
smooth
List some effects of activation of the renin-angiotensin system
increased water retention
increased BP
vasoconstriction
List two examples of nitrogenous wastes that are excreted by the kidneys
urea
creatinine
Plasma angiotensin II levels would be increased when mean arterial blood pressure is
decreased
The micturition center is located in the ____ of the brain stem
pons
The color of urine is due to the presence of a pigment called ____, produced during the breakdown of hemoglobin
urochrome
The longest and most coiled region of the renal tubule arises from the glomerular capsule and is called the
proximal convoluted tubule
List the three segments of the male urethra
prostatic urethra
membranous urethra
spongy urethra
When considering all of the pressures present within the renal corpuscle, the net filtration pressure causes the movement of fluid ____ the glomerular capillaries
out of
Water moves through specialized water channels called
aquaporins
The ___ segment of the nephron loop participates in active transport of salts
thick
Within the renal corpuscle, colloid osmotic pressure (COP) is an ____ pressure
inward
Name the effect of atrial natriuertic peptide
decreased sodium reabsorption
Name the symptoms of diabetes mellitus that are directly related to the high level of glucose in the renal tubules
polyuria
dehydration
glycosuria
Within the renal corpuscle, blood hydrostatic pressure is the pressure forcing fluid into the glomerular capsular
space
The ____ ____ consists of a descending limb and an ascending limb
nephron loop
The _____ nervous system causes vasconstriction of the afferent arterioles, reducing glomerular blood flow and GFR
sympathetic
Leaky junctions between epithelial cells in the proximal convoluted tubule that allow water to move are called
tight junctions
Angiotensin II causes vasoconstriction of
efferent arterioles and those throughout the body
Angiotensin II stimulates the posterior pituitary to secrete ____ hormone
ADH
A urine output of less than 500 ml/day is called ___ and can be due to kidney disease, dehydration, shock, and other cauess
oliguria
The pH of urine is usually mildly
acidic
The muscularis of the bladder is composed of three layers of smooth muscle called the ____ muscle
detrusor
Describe a renal calyx
cuplike or funnellike structure that collects urine
The most abundant cation in the glomerular filtrate is
sodium
Fluid and solutes reabsorbed at the proximal convoluted tubule (PCT) are picked up by what capillary bed?
peritubular capillaries
The region of the nephron that is adapted for reabsorption as seen in its length and prominent microvilli is the
proximal convoluted tubule
The capillaries forming a glomerulus have pores that allow filtration. Due to the presence of these pores, this type of capillary is classified as a ____ capillary
fenestrated
Contraction of aretiolar smooth muscle whn it is stretched allows adjustment of afferent arteriolar diameter with changes in blood pressure. This is the basis for the ____ mechanism of renal autoregulation
myogenic
Filling the bladder stimulates stretch receptors that, in turn, trigger a reflex that relaxes the internal urethra sphincter. This reflex is ____
parasympathetic
Glucose is cotransported with sodium by the sodium-glucose transporter and then removed from the basolaterial surface of thcell and into the blood by a process called
facilitated diffusion
The kidneys are about the size of a
bar of soap
The salts in the medullary ECF that contribute to its high osmolarity were transported into the ECF from the _____ limb of the nephron loops
ascending
As an enzyme, _____ functions to convert angiotensinogen to angiotensin I
renin
The hormone ____ causes increased reabsorption of sodium (and the water that follows) and secretion of potassium from the larger segments of the renal tubule
aldosterone
The collecting duct receives fluid from the
distal convoluted tube
Increased GFR results in ____ urine volume and ____ blood volume
increased; decreased
If glomerular filtration rate is too ___, fluid flows through the renal tubules too rapidly. Urine output will increase and electrolyte depletion may occur.
high
Describe the importance of the medullary ECF osmolarity gradient
allows production of very concentrated urine
Hyperglycemia in diabetes results in glucose in the urine, a condition called _____
glycosuria
Parathyroid hormone acts on the proximal convoluted tubule to inhibit ____ reabsorption and on the distal convoluted tubule to increase ____ reabsorption
phosphate; calcium