Overview of Urine Formation- Exam 2

Question 1

What are some of the function of the kidney? (major functions)

Answer 1

Control volume and concentration of body fluids
Maintains environment cells need for proper function
Rid body of waste materials produced by body or ingested
filters the plasma
resorb much of the filtrate (return to blood)
secrete some substances (remove from blood)
substances that are secreted or not reabsorbed are excreted in the urine

Question 2

What are some of the more specific functions of the kidney?

Answer 2

Excretion of metabolic waste products and foreign chemicals
Regulation of water and electrolyte balances
Regulation of body fluid osmolality and electrolyte concentrations
regulation of blood pressure
regulation of acid-base balance
secretion, metabolism, and excretion of hormones
gluconeogenesis

Question 3

What does urea reflect??

Answer 3

Amino acid metabolism

Question 4

What does creatinine reflect?

Answer 4

from muscle creatine

Question 5

What is creatine used for?

Answer 5

create phosphocreatine which serves as energy source for production of ATP in muscle.

Question 6

What day, what percent of creatine is converted to creatinine?

Answer 6

1 to 2 %

Question 7

What is uric acid from?

Answer 7

nucleic acids

Question 8

What is the end product of hgb breakdown?

Answer 8

Bilirubin

Question 9

What does fluid/salt intake usually depend on?

Answer 9

Individual eating/drinking habits

Question 10

What responds to changes in intake?

Answer 10

Kidneys

Question 11

How does acid-base regulation occur in the body?

Answer 11

Kidneys work with lungs and body-buffer systems

Question 12

What do lungs do to contribute to acid base regulation?

Answer 12

Remove carbon dioxide

Question 13

What doe kidneys do to contribute to acid base regulation?

Answer 13

Control hydrogen ion and bicarb concentration

kidneys only way to remove sulfuric and phosphoric acid; byproducts of protein metabolism

Question 14

How doe kidneys regulate erythrocyte production?

Answer 14

Secrete erythropoetin (almost all) which stimulates RBC production

Question 15

What is the major stimulus for RBC production?

Answer 15

Hypoxia

Question 16

What will have to patients will severe renal disease?

Answer 16

Develop anemia due to lack of erythropoetin production

Question 17

What happens with glucose during prolonged fasting?

Answer 17

New glucose is produced from amino acids and other items

significant quantities can be produced

Question 18

What percent of CO is renal blood flow?

Answer 18

22%

Question 19

How many mls/min is renal blood flow?

Answer 19

1100 mls/min

Question 20

What is the pressure in glomerular capillaries?

Answer 20

60mmHg; produces high rate of filtration

Question 21

What is the pressure in peritubular capillaries?

Answer 21

13 mmHg; low pressure produces high rate of fluid reabsorption

Question 22

What percent of nephrons are juxtamedullary nephrons?

Answer 22

20-30%

Question 23

What kind of reflex is micturition reflex emptying the bladder?

Answer 23

Nervous reflex

Question 24

What controls filling/emptying of the urinary bladder?

Answer 24

Autonomic spinal cord reflex

Input from cerebral cortex or brain stem

Question 25

What is the smooth muscle of the bladder?

Answer 25

Detrusor muscle

Question 26

What is the tone that holds urine in the bladder?

Answer 26

Internal sphincter; smooth muscle

Question 27

What is the voluntary control by the nervous system; conscious prevention of urination?

Answer 27

Externer sphincter; skeletal muscle

Question 28

What nerves are the primary supply to the bladder?

Answer 28

Pelvic nerves

Question 29

What is responsible for initiation micturition reflex?

Answer 29

Sensory fibers from posterior urethra

Question 30

What nerve controls the skeletal muscle fibers that provide voluntary control of external sphincter?

Answer 30

Pudendal nerve

Question 31

How is sympathetic control accomplished in the bladder?

Answer 31

Hypogastric nerves; controls blood vessels

Question 32

When are pain nerves in the ureters stimulated?

Answer 32

Blocked ureters response with intense reflex constriction which sends sympathetic stimulation back to kidneys to constrict renal arterioles (ureterorenal reflex)

Question 33

What does the composition of urine not change?

Answer 33

once it leaves the collecting ducts

Question 34

What acts as pacemaker for peristaltic contraction of smooth muscle?

Answer 34

Renal calyces

Question 35

What do renal calyces do?

Answer 35

Force urin down into renal pelvis down the ureters into the bladder

Question 36

What does increased stretch of calyces do?

Answer 36

Increases peristaltic rate

Question 37

What are renal calyces innervated by?

Answer 37

Parasympathetic (enhances peristalsis) and sympathetic (inhibits peristalsis) nerves

Question 38

What muscle prevents backflow from bladder to ureters?

Answer 38

Detrusor muscle; especially during bladder contraction

Question 39

What increases pressure with ureter to open passage to bladder?

Answer 39

Peristaltic waves down ureter

Question 40

What will occur if ureter is not long enough to pass through wall of the bladder?

Answer 40

Reflux will occur