Nursing Fund. Ch. 28

Front 1

List the organs of the Urinary System that help to excrete wastes and maintain a balance of chemicals and water in the body:

Back 1

1. Kidneys

2. Ureters

3. Bladder

4. Urethra

Front 2

List the functions of the Kidneys:

Back 2

1. Filter metabolic wastes, toxins, excess ions and water from the bloodstream and excrete them as urine.

2. Help to regulate blood volume, BP, electrolyte levels, and acid-base balance by selectively reabsorbing water and other substances.

3. Produce erythropoietin

4. Secrete renin

5. Activate vitamin D3

Front 3

Describe the structure of the kidney:

Back 3

1. Outer layer (Cortex): composed of millions of nephrons.

2. Inner layer (Medulla): consist of renal pyramids that are made up of bundles of collecting tubules.

3. Renal Pelvis: innermost area.

4. Calyces: enclose the central potion of each pyramid and direct urine into the renal pelvis.

Front 4

Define the structure of the nephrons:

Back 4

1. A doubled-walled capsule (Bowman's capsule) enclosing a glomerulus.

2. A series of filtrating tubules.

3. A collecting duct.

Front 5

List the three steps by which urine is formed:

Back 5

1. Filtration

2. Reabsorption

3. Secretion

Front 6

Describe Glomerular Filtration:

Back 6

Filtration occurs in the glomeruli. Blood enters the kidney and blood pressure forces plasma, dissolved substances, and small proteins to form a liquid called filtrate. Glomerular filtrate resembles blood plasma, except that it contains much less protein and no blood cells.

Front 7

Define Glomerular filtration rate:

Back 7

Is the amount of filtrate formed by the kidneys per minute.

Front 8

Describe Tubular reabsorption:

Back 8

The filtrate moves into the proximal convoluted tubule (99% is reabsorbed into the peritubular capillaries, 1% return as urine). Wastes and toxins that remain in the blood after filtration are actively transported into the filtrate to the distal and collecting tubules. Water and sodium are reabsorbed when ADH and aldosterone are secreted.

Front 9

What happens when the amount of fluid in the body decreases?

Back 9

The posterior pituitary gland secretes more ADH. This causes the distal and collecting tubules to reabsorb more water into the blood. At the same time, the renal cortex secretes more aldosterone, which increases the reabsorption of sodium.

Front 10

List the functions of ADH and aldosterone:

Back 10

Have the effect of maintaining normal blood volume and blood pressure.

Front 11

What happens when water in the body increases?

Back 11

ADH is suppressed and urine becomes more dilute and water continues to be eliminated.

Front 12

Describe Tubular secretion:

Back 12

Some substances (waste products and some medications) are actively secreted from the blood in the peritubular capillaries into the renal filtrate and then eliminated in urine.

Front 13

How do the kidneys help maintain normal pH balance?

Back 13

By secreting Hydrogen ions.

Front 14

How is urine transported through the ureter?

Back 14

From the collecting tubules, urine travels into the renal pelvis and enters the ureter. The ureters contract in peristaltic waves to more urine toward the bladder.

Front 15

How is urine stored in the bladder?

Back 15

The urinary bladder is a sac-like organ that receives urine from the ureters and stores it until discharged from the body. The bladder can normal store 500 mL of urine.

Front 16

How is urine transported through the urethra?

Back 16

The urethra transports urine from the bladder to the body's exterior.

Front 17

Differences between female and male urethra

Back 17

1. Female urethra is only 3-4 cm long, anchored to the anterior wall of the vagina.

2. Male urethra is about 20 cm long and passes through a surrounding gland (prostate). The male urethra also carries semen.

Front 18

How does urine leaves the bladder?

Back 18

When the internal urethral sphincter is closed, urine is kept in the bladder. When the bladder contains 200 to 450 mL or urine, the distention activates stretch receptors in the bladder wall. These receptors send sensory impulses to the voiding reflex center in the spinal cord. These impulses cause the detrusor muscle to contract and the internal urethral sphincter to relax.

Front 19

Why voiding occurs?

Back 19

When contraction of the detrusor muscle pushes stored urine through the relaxed internal urethral sphincter into the urethra.

Front 20

How is voiding voluntarily delayed?

Back 20

By inhibiting release of a second, external urethral sphincter. When the person is ready to urinate, the brain signals the external sphincter to relax, and urine flows through the urethra.

Front 21

What are the normal urination patterns?

Back 21

The kidneys produce urine at a rate of 50 to 60 mL per hour, or 1500 mL per day. When fluid intake is increased, urination will be more frequent.