Describe two effects of smoking on gas exchange in the alveoli. [2 marks]?

Question

Please take care in consideration of the marks.

Answer 1

ventilation; narrower airways, pressure on lungs, fill alveoli
- perfusion; distorts, compresses, and reduces blood vessels (hemorrhaging)
- diffusion; thickens alveolar walls, replaces alveolar walls

gas exchange—the respiratory system—and the means of delivery—the circulatory system

The human respiratory system is similar to the respiratory system of other mammals. Air moves through the nostrils into the nasal cavity, where dirt and other particles in the air are trapped by hairs andmucus. The air is also warmed, humidified, and tested for odors. The nasal cavity leads to the pharynx, where it meets air and food arriving from themouth. Air continues flowing down, passing by the larynx. The vocalcords are in the larynx. When air moves out of the body, it passes over the vocal cords. The air causes the vocal cords to vibrate, producing the sounds of our voice. The hollow voice box formed by the flexible cartilage that sur-rounds the larynx helps amplify the sounds. In males, hormones increase the size of the voice box. This enlarged voice box is called the Adam’sapple. Continuing down the tube, the trachea is surrounded by rings ofstiff cartilage that act like the rings on a vacuum-cleaner hose. The rings help maintain the tube like shape of the trachea, thus keeping it open.
In the lungs of mammals, hundreds of millions of alveoli greatly increase the size of the respiratory surfaces. In fact, the total surface area of our alveoli is 60 square meters, about one-sixth the area of a basketball court.However, the lungs on their own are completely helpless in moving airinto or out of our body. Lungs have no muscles. They cannot move andthey cannot change size on their own.All mammals, including humans, move air into their lungs by lower-ing the air pressure in the lungs

Answer 2

Due to harmful gases, the alveoli stick together thus reducing surface area for gas exchange.
Also ,
the cilia in th trachea get damaged.

Answer 3

as above