NUTRITION
THE HUMAN BODY
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
they increase the amount of energy transferred from the lungs to the blood.
|
|
|
they incrase the flexibility of the lungs as they expand during inhalation
|
|
|
they increase the volume of the lungs, allowing more oxygen to be inhaled
|
|
|
they incrase the surface area of the lungs, allowing efficient gas exchange
|
Detailed explanation-1: -The walls of the alveoli are very thin, which makes it easier for oxygen and CO2 to pass between the alveoli and very small blood vessels (capillaries). Oxygen can pass from the alveoli to the capillaries because the concentration of oxygen is lower in the capillaries than it is in the alveoli.
Detailed explanation-2: -Gas exchange occurs only in alveoli. Alveoli are made of thin-walled parenchymal cells, typically one-cell thick, that look like tiny bubbles within the sacs. Alveoli are in direct contact with capillaries (one-cell thick) of the circulatory system.
Detailed explanation-3: -The walls of the alveoli share a membrane with the capillaries. That’s how close they are. This lets oxygen and carbon dioxide diffuse, or move freely, between the respiratory system and the bloodstream.