Urinary System

autoregulation

when an increase in blood pressure stretches arterioles in the kidneys, this describes the fact that they vasoconstrict to reduce flow without feedback from the rest of the body

How many nephrons does the average adult human kidney contain (a nephron is the main functional unit of the kidney)? A Exactly 1 (Choice B) B Roughly 100,000 (Choice C) C Roughly 1,000,000 (Choice D) D Roughly 1,000

(Choice C) C Roughly 1,000,000

Presence of what in the urine, even in small amounts, is indicative of a possible problem in the renal system of a patient?

glucose

retroperitoneal

meaning "behind the abdominal cavity", this term describes organs like the kidneys that lie posterior to the abdomen serous membrane

urea cycling

the act of drawing urea out of the collecting duct, to draw water out of the nephron loop, only to put that urea back in the filtrate a few steps back

glomerulus

the ball of blood capillaries in each nephron of a kidney where bulk filtration occurs

proximal convoluted tubule

the first part in the nephron tubule, it uses active transport to reabsorb sodium and chloride ions, sugars and water from the filtrate

glomerular filtration rate

the total amount of blood that passes through the kidney's filtration organs every minute

ureter

the tube that carries urine from the kidney to the urinary bladder

Which of the following is least likely to be present in the glomerular filtrate (the filtrate produced by the nephron before it enters the loop of Henle) of a healthy adult nephron? (Choice A) A Amino acids (Choice B) B Glucose (Choice C) C Electrolytes (Choice D) D Large molecular weight protein

(Choice D) D Large molecular weight protein

Urine is formed in a three-step process: give the correct order in which these steps take place in the nephron.

Glomerular filtration, tubular reabsorption, tubular secretion

pontine micturition center

the area of the pons in the brainstem that activates detrusor activity and relaxes the internal sphincter to encourage, and allow, urination

pontine storage area

the area of the pons in the brainstem that inhibits detrusor activity and decreases the urge to pee, by increasing sympathetic nervous system activity to the urinary bladder

vasa recta

the blood vessels in the kidney that carry blood after filtration, and follow the nephron to pick up reabsorbed materials

urea

the compound made from nitrogenous metabolic wastes that the kidneys are responsible for filtering out

distal convoluted tubule

the final part of the nephron tubule that does some final reabsorption and excretion, and carries urine to the collecting duct

nephron

the functional unit within a kidney

renal pelvis

the funnel-shaped tube at the center of the kidneys that delivers urine to the exit

micturation

the official name for urination, or the release of urine from the urinary bladder

nephron loop

the part of the nephron tube that dips into the renal medulla, and returns to the renal cortex, actively removing salts from the filtrate to build up a concentration gradient

aquaporins

the protein channels that allow water molecules to cross cell membranes, their positioning is important for regulating water reabsorption in the kidneys' collecting ducts

glomerular capsule

the proximal end of the nephron tube that surrounds the ball of blood capillaries.

internal urethral sphincter

the ring of smooth muscle, therefore under the control of the autonomic nervous system, that controls the exit of the urinary bladder to the urethra

The renal system does not play a direct role in regulating which of the following? (Choice A) A Blood solute concentrations (Choice B) B Blood temperature (Choice C) C Blood pressure (Choice D) D Blood pH

(Choice B) B Blood temperature

Which of the following choices correctly traces the route of glomerular filtrate on its path to the collecting duct of a nephron? A proximal tubule, Bowman's capsule, descending loop of Henle, ascending loop of Henle, distal tubule (Choice B) B Bowman's capsule, proximal tubule, descending loop of Henle, ascending loop of Henle, distal tubule (Choice C) C Bowman's capsule, distal tubule, descending loop of Henle, ascending loop of Henle, proximal tubule (Choice D) D Bowman's capsule, proximal tubule, ascending loop of Henle, descending loop of Henle, distal tubule

(Choice B) B Bowman's capsule, proximal tubule, descending loop of Henle, ascending loop of Henle, distal tubule

As glomerular filtrate moves through the ascending loop of Henle, the filtrate becomes more dilute: why? A The ascending loop of Henle is permeable to water and ions (Choice B) B The ascending loop of Henle is permeable to ions but impermeable to water (Choice C) C The ascending loop of Henle is impermeable to water and ions (Choice D) D The ascending loop of Henle is permeable to water but not to ions

(Choice B) B The ascending loop of Henle is permeable to ions but impermeable to water

Which of the following anatomical portions of a nephron connects the Bowman's capsule to the loop of Henle? A Distal convoluted tubule (Choice B) B Connecting tubule (Choice C) C Proximal convoluted tubule (Choice D) D Collecting duct

(Choice C) C Proximal convoluted tubule

Which of the following has a rate of urinary excretion (units of solute per unit time) that is almost always identical to its rate of glomerular filtration in a healthy adult? A Sodium (Choice B) B Glucose (Choice C) C Chloride (Choice D) D Creatinine

(Choice D) D Creatinine

Which of the following has a rate of urinary excretion (units of solute per unit time) that is always much lower than its rate of glomerular filtration in a healthy adult? A Urea (Choice B) B Potassium (Choice C) C Sodium (Choice D) D Glucose

(Choice D) D Glucose

antideuretic hormone

the hormone secreted by the posterior pituitary gland in reaction to low blood pressure, this triggers the kidneys to reabsorb more water from urine

renal medulla

the inner layer of the kidneys housing the deeper nephron loops and collecting tubules that deliver urine to the center

renal corpuscle

the nephron structure that consists of a ball of blood capillaries and the surrounding tube that is the start of the nephron

urinary bladder

the organ lined with transitional epithelium, that stores urine produced in the kidneys until it can be excreted

kidney

the organ responsible for filtering toxins out of the blood, regulating water, salt, and pH in the blood, and for making urine

renal cortex

the outermost layer of the kidneys housing the glomeruli and convoluted tubules of every nephron

externa urethral sphincter

the ring of the skeletal muscle, therefore under voluntary control, that controls the exit of the urinary bladder to the urethra

detrusor

the smooth muscle layer around the urinary bladder; when it contracts it creates pressure in the bladder to force urine out

urethra

the thin tube surrounded with smooth muscle that carries urine from the urinary bladder to the outside world