Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HAP 2 > week 12 > Flashcards

week 12 Flashcards

1
Q

what is an acid?

A

any substance which can DONATE a H+ ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is a base?

A

any substance which can ACCEPT a H+ ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how is acidity or alkalinity measured?

A

Acidity or Alkalinity of a solution is measured by
its pH
– pH is inversely proportional to the concentration of H+ ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

the more acidic a solution is …..

A
  • The more acidic a solution is, the greater the
    concentration of H+ ions - the lower its pH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  • The more alkaline a solution is…..
A
  • The more alkaline a solution is, the lower the
    concentration of H+ ions - the higher the pH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what does pH affect?

A

pH affects all functional proteins and biochemical
reactions in the body, so pH is closely regulated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the Normal pH of body fluids:

A

– Arterial blood: pH 7.4
– Venous blood and interstitial fluid: pH 7.35
– Intracellular fluid: pH 7.0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is Acidosis or acidemia?

A

Acidosis or acidemia: arterial pH <7.35
– the level of acidic compounds in the body rises or when the
level of alkaline compounds in the body falls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is Alkalosis or alkalemia?

A

Alkalosis or alkalemia: arterial pH >7.45
– the level of alkaline compounds in the body rises or when the
level of acidic compounds in the body falls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is most H+ produced by?

A

Most H+ is produced by metabolism.
Phosphorus-containing protein breakdown
releases phosphoric acid into extracellular fluid
– Lactic acid from anaerobic respiration of glucose
– Fatty acids and ketone bodies from fat metabolism
– H+ liberated when CO2 converted to HCO3
– in blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what diets = more acid in blood.

A

Western diets are
generally high in
proteins
– Tends to acidify blood
by releasing more acids
during metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is Concentration of hydrogen ions regulated
sequentially by:

A

Chemical buffer systems and Physiological Buffering Systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is Chemical buffer systems and its effect?

A

Chemical buffer systems: rapid; first line of
defence
* minimises change in pH but does not remove acids or
bases from the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is physiological buffering systems and its effects?

A

Physiological Buffering Systems
* Respiratory mechanisms: act within 1–3 min
– removes carbon dioxide (which is acidic)
* Renal mechanisms: most potent, but require hours to
days to effect pH changes
– removes hydrogen (acid) and bicarbonate (base)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what happens to strong acids in water?

A

Strong acids dissociate
completely in water; can dramatically affect pH.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what happens to weak acids in water?

A

Weak acids dissociate
partially in water; are
efficient at preventing pH
changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what happens to strong and weak bases in water?

A

Strong bases dissociate
easily in water; quickly tie
up H+. Weak bases accept H+
more slowly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Buffering a Solution diagram

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is a Chemical buffer?

A

system
of one or more
compounds that act to
resist pH changes when
strong acid or base is
added
– Bind H+ if pH drops;
release H+ if pH rises

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are some Chemical Buffer Systems?

A
  1. Bicarbonate buffer
    system
  2. Phosphate buffer system
  3. Protein buffer system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what does Bicarbonate Buffer System involve?

A
  • Involves carbonic acid/H2CO3 (weak acid) and
    bicarbonate/HCO3 (a weak base)
  • The major extracellular buffer system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what happens to bicarbonate buffer system if a strong acid is added?

A
  • If strong acid added:
    – HCO3
    – (bicarbonate) ties up H+ and forms H2CO3 (carbonic acid)
    – pH decreases only slightly
    – HCO3
    – concentration closely regulated by kidneys
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what happens to bicarbonate buffer system If strong base added?

A

– It causes H2CO3 (carbonic acid) to dissociate and
donate H+ to form HCO3
– (bicarbonate)
– pH rises only slightly

24
Q

Bicarbonate Buffer System equation

A
25
Q

Bicarbonate Buffer System flowchart

A
26
Q

what is the Phosphate Buffer System?

A

Action nearly identical to bicarbonate buffer
* Involves dihydrogen phosphate/H2PO4
– (weak acid)
and monohydrogen phosphate/HPO4
2– (a weak base)
* Effective buffer in urinary system and intracellular fluid,
where phosphate concentrations are high

27
Q

what happens to Phosphate Buffer System if strong acid is added?

A
  • If strong acid added:
  • HPO4
    2– (monohydrogen phosphate) ties up H+
    and forms H2PO4
    – (dihydrogen phosphate)
  • pH decreases only slightly
28
Q

what happens to Phosphate Buffer System if strong base is added?

A
  • If strong base added:
  • It causes H2PO4
    – (dihydrogen phosphate) to
    dissociate and donate H+ to form HPO4
    2–
    (monohydrogen phosphate)
  • pH rises only slightly
29
Q

Phosphate Buffer System equation

A
30
Q

what does the Protein Buffer System include?

A

Intracellular proteins are most plentiful and powerful
buffers; plasma proteins also important
* Protein molecules are amphoteric (can function as
both weak acid and weak base)
– When pH rises (more alkaline), organic acid or carboxyl
(COOH) groups release H+
– When pH falls (more acidic), NH2 groups bind H+ to make
NH3 (Ammonia)
– Haemoglobin functions as intracellular buffer

31
Q

What is physiological buffering systems?

A
  • Chemical buffers cannot eliminate
    excess acids and bases from the body
  • Respiratory and renal systems can
    eliminate excess acids or bases from body
    – Regulate amount of acid or base in body
    – Act more slowly than chemical buffer systems
    – Have more capacity than chemical buffer systems
32
Q

What are some examples of Physiological Buffering Systems?

A

– Respiratory System
* Lungs eliminate volatile carbonic acid by eliminating CO2
– Renal System
* Kidneys eliminate nonvolatile acids produced by cellular metabolism
(phosphoric, uric, and lactic acids and ketones) to prevent metabolic
acidosis
* Kidneys also regulate blood levels of alkaline substances; renew
chemical buffers

32
Q

Respiratory Regulation of H+: what happens during co2 unloading and loading

A
  • During CO2 unloading (in the lungs), reaction shifts
    to left (and H+ incorporated into H2O)
  • During CO2 loading (in the tissues), reaction shifts
    to right (and H+ buffered by proteins)
33
Q

what is Respiratory Regulation of H+?

A

Respiratory system eliminates CO2 (“acidic”)
* A reversible equilibrium exists in blood

34
Q

Respiratory system impairment causes …

A
  • acid-base imbalances
    – Hypoventilation –> respiratory acidosis
    – Hyperventilation –> respiratory alkalosis
35
Q

what 2 types does Respiratory Regulation of H+ involve?

A

Hypercapnia (CO2 retention) and Hypocapnia (low CO2)

36
Q

what does Hypercapnia (CO2 retention) involve?

A

– Rising plasma CO2 (which leads
to rises in H+ - acidosis) activates
peripheral chemoreceptors
–> Increased respiratory rate and
depth
–> More CO2 is removed from the
blood
–> H+ concentration is reduced

37
Q

what does Hypocapnia (low CO2) involve?

A

Decreasing plasma CO2 (which
leads to decreases in H+ -
alkalosis) activates peripheral
chemoreceptors
–> decreased respiratory rate
and depth
–> More CO2 is retained in the
blood
–> H+ concentration increases

38
Q

what are the Most important renal mechanisms of acid-base balance?

A
  • Most important renal mechanisms:
    – Conserving (reabsorbing) or generating new HCO3-
    – Excreting HCO3-
39
Q

what happens When the body is in alkalosis:

A

When the body is in alkalosis:
– Kidneys secrete HCO3-
– Reclaim H+ to acidify blood

40
Q

what happens when the body is in acidosis:

A

– Kidneys secrete H+
– Reclaim HCO3- to increase the alkalinity of the blood

41
Q

how does Rate of H+ secretion change with extracellular fluid
CO2 levels?

A

– ^ CO2 in peritubular capillary blood –> ^ rate of H+ secretion
– System responds to both rising and falling H+ concentrations

42
Q

what are the Abnormalities of Acid-Base
Balance?

A
  • Effects of Acidosis and Alkalosis.
43
Q

what are the Effects of Acidosis and Alkalosis?

A

– Blood pH below 6.8 –> depression of CNS –> coma –> death
– Blood pH above 7.8 –> excitation of nervous system –>
muscle tetany, extreme nervousness, convulsions,
death often from respiratory arrest

44
Q

what is Respiratory acidosis and alkalosis caused bu and what is it?

A

Respiratory acidosis and alkalosis
* Caused by failure of respiratory system to perform pHbalancing role
* Single most important indicator is blood PCO2

45
Q

what is Metabolic acidosis and alkalosis?

A
  • All abnormalities other than those caused by PCO2 levels in
    blood; indicated by abnormal HCO3- levels
46
Q

what is the most important indicator of adequacy of
respiratory function?

A

Most important indicator of adequacy of
respiratory function is PCO2 level (normally
35–45 mm Hg)

47
Q

what does PCO2 above 45 mm Hg mean?

A

PCO2 above 45 mm Hg –> respiratory acidosis
* Common cause of acid-base imbalances
* Due to decrease in ventilation or gas exchange
* CO2 accumulates in blood
* Characterised by falling blood pH and rising PCO2

48
Q

what does PCO2 below 35 mm Hg mean?

A

– PCO2 below 35 mm Hg–>respiratory alkalosis
* Common result of hyperventilation often due to stress or
pain
– CO2 eliminated faster than produced

49
Q

what is Metabolic acidosis and what does it cause?

A
  • Metabolic acidosis – low blood pH and HCO3
    – Causes:
  • Ingestion of too much alcohol (–> acetic acid)
  • Excessive loss of HCO3- (e.g., persistent diarrhea)
  • Accumulation of lactic acid (exercise or shock), ketosis in
    diabetic crisis, starvation, and kidney failure
50
Q

what is Metabolic alkalosis and what does it cause?

A

Metabolic alkalosis (much less common than
metabolic acidosis)
– Indicated by rising blood pH and HCO3-
– Causes include vomiting of acid contents of stomach or
by intake of excess base (e.g., antacids)

51
Q

what happens when there is a acid-base imbalance due to malfunction of
physiological buffer system?

A

If acid-base imbalance due to malfunction of
physiological buffer system, other one tries to
compensate
– Respiratory system attempts to correct metabolic
acid-base imbalances
– Kidneys attempt to correct respiratory acid-base
imbalances
* Respiratory system cannot compensate for
respiratory acid-base imbalances
* Renal system cannot compensate for acid-base
imbalances caused by renal problems

52
Q

what does changes in respiratory rate and depth mean In renal metabolic acidosis?

A

– In metabolic acidosis:
* High H+ levels stimulate respiratory centres
* Rate and depth of breathing elevated
* Blood pH is below 7.35 and HCO3
– level is low
* As CO2 eliminated by respiratory system, PCO2 falls below
normal

53
Q

what does changes in respiratory rate and depth mean In renal metabolic alkalosis?

A

– In metabolic alkalosis:
* Slow, shallow breathing
* Allows CO2 accumulation in blood
* Blood pH is over 7.45 and HCO3
– level is high
* As CO2 is retained, PCO2 rises to normal levels

54
Q

what is the Renal Compensation for
Respiratory Acid-Base Imbalance.

A
  • Hypoventilation causes elevated PCO2 and low
    pH
    – Respiratory acidosis
    – Renal compensation: increases HCO3
    – levels by
    retaining HCO3
    – and secreting H+
  • Hyperventilation causes low PCO2 and high pH
    – Respiratory alkalosis
    – Renal compensation: decreases HCO3
    – levels by
    increasing the secretion of HCO3
    – and retaining H+
55
Q
A

HAP 2 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions