Brainscape's Knowledge GenomeTM

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


See full index

Physiology: Exam 3 > Lecture 6a: Acid Base Balance I > Flashcards

Lecture 6a: Acid Base Balance I Flashcards

1
Q

Why is Acid-Base Balance
in the Body Important? (4 points)

A
  1. Our diets contain many acids and bases; cellular catabolism of foodstuffs produces the majority of acids and bases in our bodies.
  2. Bases normally lost in feces; the net effect of accumulation of acid in body fluids.
  3. Cellular functions are sensitive to pH.
  4. Acid must be excreted for the normal physiological function of cells and organs.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Acids ____ H+ ions. Bases ____ H+ ions

A

donate, receive

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

____ dissociate completely or almost completely into H+ and their conjugate base.

A

Strong acids

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

____ are only slightly ionized in aqueous solution

A

Weak acids

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

What is a buffer?

A

A mixture of substances in an aqueous solution that can resist changes in H+ ion concentration when strong acids or bases are added.

Buffers are usually a combination of a weak acid and its conjugate base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Acidity is determined by what?

A

The activity of H+ ions in a solution

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

What is the pH scale?

A

A convenient way to express a wide range of acidities

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

pH=

A

-log(H+ activity)

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

In the body, H+ activity is equal to _________. Therfore pH= _________

A
  • H+ concentration
  • pH=-log[H+]
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

pH of arterial blood is normally close to?

A

7.40

[ ]=40 nM

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

What is the normal range for pH of arterial blood?

A

7.35 to 7.45

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

Under pathologic conditions, the arterial blood pH can range from ____________.

A

6.9 to 7.8

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

What is the arterial blood pH w/ Acidemia?

A

pH<7.35

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

What is the arterial blood pH w/ Alkalemia?

A

pH>7.45

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

What are the sources of Acid in the body?

A
  1. Cellular metabolism (main source)
  2. Accidentally Ingested Fixed Acids
  3. Abnormally High Fixed Acid Production (e.g. Diabetic Ketoacidosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 5 types of cellular metabolism occuring in our body that serves as a source of acid?

A

1. Oxidation of glucose and fatty acids (major)
2. Oxidation of sulfur-containing amino acids
3. Oxidation of phosopholipids/phosphoprotein
4. Conversion of NH4Cl to Urea
5. Anaerobic metabolism of glucose

17
Q

Cellular Metabolism

Oxidation of glucose and fatty acids (major)

  1. Produces?
  2. Removed by lungs or kidneys?
  3. Volatile or Fixed acid?
A
  1. Produces CO2
  2. CO2 removed by lungs
  3. Volatile Acid
18
Q

Cellular Metabolism

Oxidation of sulfur-containing amino acids

  1. Produces?
  2. Removed by lungs or kidneys?
  3. Volatile or Fixed acid?
A
  1. Produces sulfuric acid (H2SO4)
  2. Removed by kidneys
  3. Fixed Acid
19
Q

Cellular Metabolism

Oxidation of phosopholipids/phosphoproteins

  1. Produces?
  2. Removed by lungs or kidneys?
  3. Volatile or Fixed acid?
A
  1. Produces phosphoric acid (H3PO4)
  2. Removed by kidneys
  3. Fixed Acid
20
Q

Cellular Metabolism

Conversion of NH4Cl to Urea

  1. Produces?
  2. Removed by lungs or kidneys?
  3. Volatile or Fixed acid?
A
  1. Produces HCl
  2. Removed by kidney
  3. Fixed Acid

Urea comes from liver

21
Q

Cellular Metabolism

Anaerobic metabolism of glucose

  1. Produces?
  2. Conversion?
  3. Volatile or Fixed acid?
A
  1. Produces Lactic Acid
  2. May be converted to CO2
  3. Can be Volatile or Fixed
22
Q

Which two organs use alot of bicarbonate?

A

Liver and Kidney

Liver uses bicarb + aluminum chloride to create urea

23
Q

Regulation of body pH is acheives by what 3 mechanisms?

Acid-Base Balance

A
  1. Chemical Buffering (immediate)
    Respiratory Compensation (fastest)
    Renal Compensation (Long-term)
24
Q

What does the graph below show?

A
  • Distilled water has no buffer system and you see the pH decrease very fast wehn around 25mEq H+ were added.
  • In vivo there is a buffering system so it can maintain pH and resist change in acidity
25
Q

What is the Henderson-Hasselbalch
Equation?

A
[A-]=conjugate base, [HA]=conjugate acid
26
Q

List the 3 main important buffer system pairs and their location

A
  • HCO3-/CO2: Plasma, Interstitial, Cells (mainly ECF)
  • Protein^n-/HnProteins: RBCs, Plasma, Cell; Hemoglobin & others (ECF + ICF)
  • Phosphate^n-/HnPhosphate (HPO42-/H2PO4): Intracellular (mainly ICF)
27
Q

What is the first line of defense to resist change in acidity?

A

Fast Chemical Buffering in plasma

  • Strong acid + Buffer salt -> Neutral salt + Weak acid

Review Slide 11

28
Q

Explain the Isohydric Princple

A
  • Each of the 3 major buffering systems all have different pK values each system changes concentration
  • All buffer to the same pH (7.4)
29
Q

What are 3 special characteristics of the
bicarbonate buffer system?

A
  • High [HCO3-]
  • [HCO3-]/CO2 = 20 : 1
  • Open System: Controlled pCO2

Review Slide 13, 14 &15

30
Q

What does this graph represent?

A

Titration Curves for the Bicarbonate
and Phosphate Buffer Systems.

  • By the time you lose all the acid or base the buffer system is gone.
  • That is why you see a significant pH jump on the left and most right of the graph.
  • The buffer system is in the middle area and you see a gradual change in pH
31
Q

What is essential for optimal physiological function of cells and organ?

A

Maintenance of an optimal plasma and ECF pH

32
Q

What accounts for most acid production in the body?

A

Catabolism of dietary foodstuffs

33
Q

Volatile acids result from what?

A

Aerobic carboyhdrate and lipid metabolism, and can be converted to gas and removed by the lungs

34
Q

Fixed acids result from what?

A

Other metabolic processes or direct intake, cannot be removed by the lungs, and are typically removed by the kidney

35
Q

____ prevents drastic changes in body fluid acidity.

A

Chemical Buffering

36
Q

True or false: A weak acid dissociates less in solution than a strong acid

A

TRUE

37
Q

Which is produced and excreted in greater quantity?
A. Volatile Acid
B. Fixed Acid

A

A. Volatile Acid

38
Q

What is the normal [HCO3-]/[CO2] ratio in arterial blood?

A

20:1

Physiology: Exam 3 (10 decks)

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