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

Question

Please take care in consideration of the marks.

Answer 1

1) It causes emphysema
2) It makes permanent enlargement of alveoli . As a result heart has to pump more blood which may cause over strain which may even cause death.
(I think for a question of 2 marks , 2 points are enough.)

Answer 2

One of the gases present in cigarette smoke is Carbon Monoxide. This binds to haemoglobin in the red blood cells more readily than oxygen, preventing the movement of oxygen from the alveoli into the blood stream via gas exchange. Smoking also paralyses the cillia in the trachea, which normally waft mucas and dirt away from the lungs to the back of the throat. The paralysis of the cillia prevents this, causing mucus to fall into the lungs, causing coughing. Over time, this can lead to the alveoli "bursting", a condition known as emphesema. When the alveoli are damaged in this way, gas exchange is no longer possible. It is for this reason that sufferers of severe emphesema are forced to use oxygen.

Answer 3

The above answer is perfect - you'd probably get the two marks.

However, in ther long term effect, smoking increasing the risk of atherosclerosis and the diameter of the pulmonary artery leading to the alveoli will be decreased. Consequently, the gas exchange will decrease.

Answer 4

1. smoking damages the microscopic hairs on the lining of the trachea meaning your lungs are not able to properly remove the mucus which traps the dirt and bacteria.

2. Red blood cells pick up oxygen in the lungs to transport it to other cells in the body to be used for respiration. Carbon Monoxide found in cigarette smoke binds to the red blood cells instead of the oxygen, and when the red blood cell reach the cells the carbon monoxide will not leave the red blood cells and so you have less red blood cells available to carry the oxygen

Answer 5

Toxins can bind with oxygen thus changing its performance in the body. Toxins can destroy the fragile cells of the alveolar thus preventing proper venting of oxygen into the body and preventing proper venting of carbon dioxide from the body. The toxins, by also making the cells more ridged, can interfere in the same ventilation mechanically.Ni