acid base balance

Question 1

what is an acid

Answer 1

any compound which forms protons in solution

Question 2

what is a base

Answer 2

any compound which combines with H+ in solution(then termed alkali)

Question 3

what is acididosis

Answer 3

low plasma pH

Question 4

alkalosis

Answer 4

high plasma pH

Question 5

what is normal pH range

Answer 5

7.35-7.45 avg 7.4

Question 6

what do fluctuations of protons have effects on

Answer 6

excitability of muscle and nerves
enzyme activities
K+ levels

Question 7

how do changes in protons affect K+ levels

Answer 7

too many/few ions on either side may affect the cotransport system

Question 8

sources of acid/alkali

Answer 8

volatile acids

fixed acids

Question 9

what is a volatile acid

Answer 9

will leave the solution

produced by oxidative metabolism

Question 10

what is a fixed acid

Answer 10

acid that don’t leave solution

generated by catabolism aa, phospholipids and nucleic acids

Question 11

what systems are involved to keep H+ levels

Answer 11

blood and tissue buffer
respiration
renal

Question 12

where are buffers present

Answer 12

blood
extra/intracelluar fluid
urine

Question 13

examples of buffers

Answer 13

HCO3-

hamoglobin

Question 14

explain carbonic acid use as a buffer

Answer 14

formed/broken down to water and carbon dioxide
also formed from H+ and bicarbonate ion (HCO3-)
i.e. mopping up the H+ ions

Question 15

what is the bicarbonate reserve

Answer 15

maintenance of a level of bicarbonate ions

sodium bicarbonate dissociates into sodium and bicarbonate ions

Question 16

explain haemoglobin buffering????

Answer 16

left over CO2 combines with water forming carbonic acid
dissociated to form proton and carbonate ions
released by erythrocytes to exchange for chloride ions

Question 17

phosphate buffering

Answer 17

able to pick up or release protons

acts as weak acid

Question 18

limitiations of buffering

Answer 18

only temporary solution to acid base imbalance
H+ ions not eliminated
supply of buffers limited§

Question 19

respiratory acid base control

Answer 19

can eliminate or retain CO2

CO2 can be used to make carbonic acid

Question 20

what would be there response to acidosis

Answer 20

stimulate brain and arteriole receptors
increase respiration
decrease in blood CO2
decease in carbonic acid 
increase in pH (homeostasis restored)

Question 21

Renal acid base control

Answer 21

3rd line
only mechanism to excrete fixed acids
regulates levels of bicarbonate

Question 22

regulating existing bicarbonate ions

Answer 22

cells line lumen of proximal tubule
protons generated and exchanged for sodium across membrane
filtrate from blood contains carbonate ions
binds with protons to form bicarbonic acid
enzyme able to act on and to form water and CO2 taken up by tubular epithelial cells
CO2 and water combine to form bicarbonate again

Question 23

other systems to remove protons in kidney

Answer 23

new dicarbonic acid is generated (H20 +CO2)
dissociates into H+ and carbonic acid
h+ joined with phosphate ion to be excreted

or glutamine broken down into ammonia and bicarbonate
ammonia joins with H+ for amminum to be excreted

Question 24

causes of acid base disturbances

Answer 24

metabolic
acidosis - lactic
alkalosis - intake of alkali
respiratory
acidosis - airway obstruction
alkalosis - breathing too much

Question 25

treatment

Answer 25

identify cause

use saline, potassium, dilute HCL, bicarbonate