Buffers

Question 1

What is pH?

Answer 1

Amount of H+ ions

Question 2

Importance of pH in bio systems (blood)

Answer 2

Proper functionality
- bio systems cannot handle huge changes in pH

Question 3

Optimal pH level of blood

Answer 3

7.4 (more basic)

Question 4

What maintains blood pH?

Answer 4

3 different types of buffer systems
1) protein
2) phosphate
3) bicarbonate

Question 5

Buffer

Answer 5

A solution (or substance - made of weak acids and bases) that has the ability to MAINTAIN pH and BRING IT BACK to its OPTIMAL level

Question 6

How do buffers perform their function?

Answer 6

By adding or removing H+ ions

Question 7

How do protein buffers work in blood?

Answer 7

• lower pH if it rises above 7.4 by making the blood slightly more acidic (release more H+ ions)
• increase pH if falls below 7.4 by making it more basic/decreasing acidity (take up H+ ions)

Question 8

Protein role in Buffer Systems

Answer 8

Proteins are the most important and widely operating buffers in the body fluid

Question 9

Zwitterion

Answer 9

An ion that is simultaneously negatively and positively charged
- ex. amino acids
NH3(+)-CHR-COO(-)

Question 10

Types of protein buffers

Answer 10

Intracellular or extracellular

Question 11

Main protein buffer function

Answer 11

Intracellular
- includes hemoglobin (transport oxygen)
- plasma proteins function as buffers

Question 12

Protein buffers include

Answer 12

Basic and acidic protein buffer groups that acts as H+ depletors or doners

Question 13

Phosphate Buffer System ions

Answer 13

1. Hydrogen phosphate
   HPO4 (2-)
2. Dihydrogen phosphate
   H2PO4 (1-)

Question 14

How do phosphate buffers work in blood?

Answer 14

• if the pH drops below 7.4 (acidic), HYDROGEN PHOSPHATE accept all additional H+ ions to reestablish equilibrium between OH and H ions
• if the pH increases above 7.4 (basic), DIHYDROGEN PHOSPHATE releases H+ to increase pH

Question 15

Bicarbonate Buffer System function

Answer 15

• maintain pH in mammal blood
• major role in formaion of acid in stomach
• neutralise pH of chyme that enters small intestine
• manages acid/base imbalances
• manages release of excess CO2 (by-product of cellular respiration)