The events of inspiration begins with the;
Impulses are conducted on the phrenic nerve to muscle fibers in the diaphragm contracting them.
As the dome shaped diaphragm moves downward the thoracic cavity expands.
At the same time the external intercostal muscles may contract raising the ribs and expanding the thoracic cavity further.
The intra-alveolar pressure decreases
Atmospheric pressure greater than intra-alveolar pressure forces the air into the respiratory tract through the air passages.
The lungs fill with air.
D. More economically developed countries
Answer:
The correct answer is option c. "Enzyme lowers the activation energy".
Explanation:
The activation energy is defined as the amount of energy needed for a reaction to take place. Enzymes catalyze reactions by lowering the activation energy, which speeds up the reaction and increases its rate. Enzymes put a substrate in its active site, which facilitates the reaction and makes more likely that it collides with its subsequent substrate.
