ANS230 Lecture 20/21 : Acid and Base I + II

What does pH stand for?

Potential of Hydrogen

What is the formula for pH?

-log (hydronium concentration)

Is the hydrogen ion concentration in physiological fluids large or small?

Small

What can if the hydrogen ion concentration is too high in a body.

It could bind to proteins, resulting in the alteration of shape, change, and function. This could result in animal death

What is physiological pH?

pH = 7.35

What are the two important aspects of the log function for pH?

• It is a NEGATIVE log function, so as Hydrogen ions increase, pH decreases

• Non-linear relationship

What two molecules are produced constantly by cells during normal metabolism?

CO2 and Hydrogen

What carries oxygen to the cells and CO2 out of the cells?

Red blood cells

What are the 3 ways in which CO2 is removed?

• Dissolved in Plasma (10%)

• As Bicarbonate Ions - Primary Buffer System (70%)

• As Carbaminohemoglobin RBC (20%)

What is the main route of hydrogen disposal or utilization?

Bicarbonate Buffer System

What is the main source of bicarbonate?

Saliva

What does carbonic anhydrase do?

It is an enzyme that moves CO2 in acid form to Carbonic Acid

In the Bicarbonate Buffer System, if you have a rapid buildup of CO2, what happens?

↑ CO₂ → shifts the reaction to the right

More carbonic acid (H₂CO₃) forms

This dissociates into H⁺ (hydrogen ions) and bicarbonate

↑ H⁺ → pH decreases

How long does it takes chemical buffers to take effect?

Seconds

What are the three examples of chemical buffers?

• Bicarbonate

• Phosphate

• Proteins (Hemoglobin)

How long does it take the Respiratory System to adjust in the bicarbonate system?

Minutes

How are CO2 levels adjusted in the bicarbonate system?

Ventilation (breathing)

How long does it take the renal/urinary system to adjust in the bicarbonate system?

Hours to Days

How does the Renal/Urianry System work in in the bicarbonate system?

Excretes H+ and reabsorbs HCO3-

What results as a result of low HCO3-, and how does the body respond to it?

Metabolic Acidosis, Hyperventilation (blow off CO2)

What results as a result of high HCO3-, and how does the body respond to it?

Metabolic Alkalosis, Hypoventilation (retain CO2)

What results as a result of high CO2 and how does the body respond to it?

Respiratory Acidosis; Kidneys excrete H+, retain HCO3-

What results as a result of low CO2, and how does the body respond to it?

Respiratory Alkalosis; Kidneys retain H+, excrete HCO3-

What two groups on proteins are a good source of buffering?

The Carboxyl Group and Amine Group

True/False, Proteins function as acids or bases anda re not limited to one or the other

True

What is the noninvasive biological sample you can get from about any species to determine pH?

Urine

What pH is a high protein diet associated with?

low pH (acidic)

What pH is a diet consisting of plants and fibers (or any higher structural carb) associated with?

High pH (alkaline)

What pH level is associated with the consumption of milk?

Acidic urine

What common system illness affects acid-base balance in the urine?

UTI ((Urinary Tract Infection)

How do UTI’s affect pH

They increase the pH due to urease-producing bacteria that converts urea to ammonia

What is Glucosuria

Excess glucose excretion in the urine

When does glucosuria particularly occur?

During diabetes

What particular animal is susceptible to glucosuria during stress?

Cat

What set of compounds are good to monitor in the urine?

Ketone Bodies/Ketones

What ketone is measured in the pH strip tests?

Acetoacetic Acid

What are ketone bodies linked to in urine/

Metabolic Acidosis, as they lower pH levels

What level of pH is needed in the lumen of the stomach for digestion?

Low

What is needed to initiate the digestion of proteins?

A very high concentration of H+

What anion is secreted by the stomach alongside H+

Cl-

What does HCl do in aqeuous solutions?

Disassociates Completely (ex H+ and Cl-)

Are there buffers in gastric fluid?

No

What does the free hydrogen ion do in the body?

It binds to proteins, breaks them down, and allows the enzymes to further denature the protein and prepare it for absorption

Which has a higher pH curve, high forage or high grain?

High Forage

What does fermentation result in?

A drop in pH

Is a drop in rumen pH recieved well by microbial populations?

No

What do cellulolytic bacteria need to do their job?

Relatively higher pH