Question

LABORATORY 9 Lab Report: Respiratory System: Physiology 1. Purpose of this exercise: Procedure 1. View histological slides pertaining to the respiratory system. 2. View torso and Respiratory models and diagrams. Questions 1. State the role carbon dioxide plays in maintaining a consistent blood pH. 2. There are two pairs of vocal folds. Which pair are the true vocal cords (superior/inferior)? Explain how the vocal cords produce speech?

Answer 1

1.CO2 plays a major role in the maintenance of blood PH levels. Blood pH is tightly regulated by a system of buffers that continuously maintain a normal range of PH 7.35 to 7.45. Carbon dioxide in the blood is a by-product of metabolism. In blood Carbon dioxide (CO₂) is stored mostly as bicarbonate (HCO₃). Bicarbonate is an alkaline substance that helps the body to maintain its pH levels or the balance between acid and alkaline.

The buffer that maintains the pH of human blood involves carbonic acid (H₂CO₃), bicarbonate ion (HCO₃^–), and carbon dioxide (CO₂). When bicarbonate ions combine with free hydrogen ions and become carbonic acid, hydrogen ions are removed, moderating pH changes. Similarly, excess carbonic acid can be converted into carbon dioxide gas and exhaled through the lungs; this prevents too many free hydrogen ions from building up in the blood and dangerously reducing its pH; likewise, if too much OH^– is introduced into the system, carbonic acid will combine with it to create bicarbonate, lowering the pH. .

The role of CO2 in PH regulation was noted by the  Danish physiologist Christian Bohr. The Bohr effect states that arterial hypocapnia will cause reduced oxygen release in tissue capillaries.As hemoglobin's oxygen binding affinity is inversely related both to acidity and to the concentration of carbon dioxide. Since carbon dioxide reacts with water to form carbonic acid, an increase in CO₂ results in a decrease in blood pH, resulting in hemoglobin proteins releasing their load of oxygen. Conversely, a decrease in carbon dioxide provokes an increase in pH, which results in hemoglobin picking up more oxygen.