Respiration and Breathing system | strip-header-layout

Chapter 3: Respiration and Breathing System

Larynx (Voice Box): Used to make sound
Trachea: Connects the lung to the outside world
Rings of Cartilage: Strengthen th trachea
Right\Left Bronchus: Branches of the trachea
Bronchiole: Carries air throughout the lung
Alveoli: Air sacs where gaseous exchange takes place
Rib cage, inter-coastal muscles and diaphragm: All involved in the mechanism of taking a breath (i.e inhaling and exhaling)

Breathing is also known as external breathing
The function of the breathing system is to take in oxygen and to excrete carbon dioxide and water vapour
The lungs, bronchi, trachea, bronchiole and alveoli are vall parts of the breathing system
The diaphragm, the ribe cage and intercostal muscles are involved in the mechanism of taking a breath
Air enters the lungs when the diaphragm pulls down and the rib cage expands

In the breathing system we take in oxygen and this enters the bloodstream through the alveoli
This blood circulates through the body and provides oxygen to the cells in the body
The blood containing oxygen is a bright red and unoxygenated blood is a more purple colour as you can see in the diagram
As the blood circulates through the body the oxygen is used up in cells and the cells then excrete carbon dioxide which enter the blood stream
This unoxygenated blood returns to the alveoli the carbon dioxide is removed and oxygen enters the blood and the cycle begins again
The carbon dioxide removed in the alveoli is then excreted by being exhaled

Oxygen Carbon Dioxide

Inhaled air: 21% .03%

Exhaled air: 16% 4%

As you can see from the table above there is more carbon dioxide in exhaled air than inhaled air
This is due to the fact that the cells in the body take in oxygen from the blood and then excrete carbon dioxide in to the bloodstream
As a result the blood now contains less oxygen and more carbon dioxide and this is then excreted through the alveoli leading to this increase in carbon dioxide