mastering a&p urinary system

renal cortex

-most superficial region of kidney -filtration of blood

functions of the urinary system

-regulates plasma concentrations of electrolytes -contributes to stabilizing blood pH -regulates blood volume -eliminates organic waste products

parts of the urinary system

-ureter. -urethra. -kidney. -urinary bladder.

A healthy adult typically produces ________ of urine per day.

1200 mL

Typical renal blood flow is about ________ percent of cardiac output under resting conditions.

25

order in which blood passes through these vessels to the kidney

4. renal artery 3. interlobar artery 2. arcuate artery 6. cortical radiate artery 1. afferent arteriole 5. glomerulus 7. efferent arteriole 8. peritubular capillary

flow of newly produced urine

5) renal papilla 1) minor calyx 4) major calyx 2) renal pelvis 3) ureter

direction of urine flow from formation to exiting the kidney

Cortex, medulla, renal pelvis, ureter

cortex

Eighty-five percent of nephrons in the human kidney are located in the ________ and have short nephron loops.

Where filtration exclusively occurs in the kidney

across the filtration membrane in the renal corpuscle

Substances larger than ________ do not pass through the filtration membrane.

albumin

diffuse into the bloodstream as diffusion takes place across the dialysis membrane

bicarbonate ions

When the level of ADH (antidiuretic hormone) decreases,

both more urine is produced and the osmolarity of the urine decreases.

The ability to form concentrated urine depends on the functions of

both the distal convoluted tubule and the collecting duct.

minor calyx

collects the urine produced by a single kidney lobe

mesangial cells

control capillary diameter and the rate of capillary blood flow.

Juxtamedullary nephrons

essential to water conservation and the production of concentrated urine

The nephron loops of juxtamedullary nephrons have an important function that other parts of the nephron do not share. What is this function?

establishing the concentration gradient in the renal medulla

not a function of the urinary system

excretes abundant protein molecules

glomerular hydrostatic pressure

favors the filtration pressure

renal corpuscle

filters the blood

three distinct processes of urine formation in the kidney

filtration, reabsorption, and secretion

structures of the renal corpuscle

glomerular capsule and glomerulus

chronic renal failure

gradual loss of renal function

Acute renal failure

immediately life-threatening condition. However, if an individual survives the incident, full recovery is often possible

Stretch receptor impulses activate sympathetic outflow.

inhibits micturition by relaxing the detrusor and contracting the internal urethral sphincter

uric acid

lowest concentration (mg/dL) in normal urine

urea

most abundant waste solute in urine

dysuria

painful or difficult urination

proximal convoluted tubule

portion of the nephron and collecting system where the most reabsorption occurs

hilum

prominent indentation on the medial surface of the kidney

NOT a normal constituent of urine

proteins

filtrate first passes from the glomerular capsule to the

proximal convoluted tubule

primary function of the proximal convoluted tubule

reabsorbing nutrients

filtration

results from blood pressure that forces water and solutes across the membranes of the glomerular capillaries and into the capsular space

The left kidney lies ________ to the right kidney.

slightly superior

secretion (kidney function)

solutes are transported from the peritubular fluid across the tubular epithelium and into the tubular fluid

renin

triggers formation of angiotensin I

normal constituents of urine

uric acid. urea. hydrogen ions. creatinine.

produced by kindeys in response to increased levels of aldosterone

urine with a lower concentration of sodium ion

When does urine production end?

when the fluid enters the renal pelvis

Renal medulla

where renal columns are located

pyelogram

x-ray image of the urinary system

All of the following are true of the kidneys except that they are

TRUE: -held in place by the renal fascia. -surrounded by a fibrous capsule. -located in a position that is retroperitoneal. -covered by peritoneum. NOT TRUE: -located partly within the pelvic cavity.

Blood colloid osmotic pressure tends to draw water out of the filtrate and into the plasma. Why?

The solute concentration in the blood exceeds that within the filtrate.

renal pyramids

Triangular or conical structures located in the renal medulla

nephron loop

U-shaped segment of the nephron

collecting system

Variable secretion of potassium and hydrogen ions is a specific function of which renal structure?

fibrous capsule

Which structure is composed of a layer of collagen fibers that covers the entire outer surface of the kidney?

acute renal failure

sudden loss of renal function

renal failure

the inability of the kidneys to excrete adequately to maintain homeostasis

Dialysis

the process of using an artificial semipermeable membrane to remove wastes and retain plasma proteins in the blood of a person whose kidneys are not functioning properly.

What structures enter and exit the kidney at the hilum?

the renal artery and renal nerves enter; the renal vein and ureter exit at the hilum

renal papilla

tip of the medullary pyramid

What is the function of the vasa recta?

to collect and transport water and solutes within the renal medulla in association with the juxtamedullary nephron