Gas Exchange, Ventilation and Smoking Flashcards
Where is gas exchange located?
In the thorax - the upper part of the body.
Describe the trachea?
-Windpipe
-Surrounded by C shaped rings of cartilage which keep the trachea open but make swallowing easier
What are the bronchi?
The trachea splits to form the two bronchi - these tubes lead to the lungs. They are also surrounded byu cartilage rings
What are the bronchioles?
The bronchi divide/branch into smaller and smaller tubes called bronchioles, which carry air deep into the thorax
What is the pleural membrane?
It forms a double layer between the lungs and thorax walls. In between the membranes there is a thin layer of pleural fluid. Together they form an airtight seal and prevent the lungs from sticking to the thorax wall as they inflate and deflate.
What is the function of the ribs?
They protect the organs inside the thorax.
What is the function of the intercostal muscles?
They help connect the bones (of the ribs) and are important in moving air in and out of the lungs.
What happens to the diaphragm, intercostal muscles, ribs, volume and pressure during INHALATION?
-Diaphragm contracts, moving down and flattening
-Intercostal muscles contract
-Rib cage moves up and out
-Volume of thorax increases
-Air pressure in thorax decreases (air pressure in thorax is less than atmospheric pressure, causing air to move into lungs)
What happens to the diaphragm, intercostal muscles, ribs, volume and pressure during EXHALATION?
-Diaphragm relaxes, moving up and doming
-Intercostal muscles relax
-Rib cages moves down and in
-Volume of thorax decreases
-Air pressure in thorax increases (causing air to move out
What is the total surface area of alveoli in the lungs?
60m squared
Cigarettes contain how many chemicals?
Over 4,000
How many carcinogens are in tobacco smoke?
At least 17, including tar.
What are carcinogens?
They are chemicals which can alter DNA and increase the risk of cancer.
What might happen if a pregnant women smokes?
The baby will receive less oxygen and as a result is likely to weigh less at birth.
What does tobacco smoke do to the body?
Tobacco smoke contains carbon monoxide. This irreversibly binds to the haemoglobin, forming carboxyhaemoglobin, and so reducing the amount of oxygen transported by the blood.
