The Respiratory System


What is the Respiratory System?

The respiratory system, which includes air passages, pulmonary vessels, the lungs, and breathing muscles, aids the body in the exchange of gases between the air and blood, and between the blood and the body’s billions of cells. Most of the organs of the respiratory system help to distribute air, but only the tiny, grape-like alveoli and the alveolar ducts are responsible for actual gas exchange. In addition to air distribution and gas exchange, the respiratory system filters, warms, and humidifies the air you breathe. Organs in the respiratory system also play a role in speech and the sense of smell. The respiratory system also helps the body maintain homeostasis, or balance among the many elements of the body’s internal environment. The respiratory system is divided into two main components including the upper respiratory tract and the lower respiratory tract.


What is The Upper Respiratory Tract?

Composed of the nose, the pharynx, and the larynx, the organs of the upper respiratory tract are located outside the chest cavity.

Nasal cavity: Inside the nose, the sticky mucous membrane lining the nasal cavity traps dust particles, and tiny hairs called cilia help move them to the nose to be sneezed or blown out.

Sinuses: These air-filled spaces alongside the nose help make the skull lighter.

Pharynx: Both food and air pass through the pharynx before reaching their appropriate destinations. The pharynx also plays a role in speech.

Larynx: The larynx is essential to human speech.


What is The Lower Respiratory Tract?

Composed of the trachea, the lungs, and all segments of the bronchial tree (including the alveoli), the organs of the lower respiratory tract are located inside the chest cavity.

Trachea: Located just below the larynx, the trachea is the main airway to the lungs.

Lungs: Together the lungs form one of the body’s largest organs. They’re responsible for providing oxygen to capillaries and exhaling carbon dioxide.

Bronchi: The bronchi branch from the trachea into each lung and create the network of intricate passages that supply the lungs with air.

Diaphragm: The diaphragm is the main respiratory muscle that contracts and relaxes to allow air into the lungs.

the respiratory systemupper and lower respiratory tractrespiratory system functions


What is the Function of The Respiratory System?

The primary function of the respiratory system is to supply the blood with oxygen. Oxygen is needed in all parts of the body for life to continue. This transport of oxygen begins when we inhale each breath sees us inhale oxygen and carbon dioxide. The respiratory system starts with the mouth and the nose air is brought in, then passes through the larynx and the trachea into the chest cavity. The three main stages of the respiratory system function include


1. Transportation of Oxygen

oxygen respiratory system

Transporting oxygen is a key part of our bodies function to keep us alive.


What transports Oxygen?

Our cardiovascular system plays a vital role in transportation of oxygen around the body.


How does the movement of oxygen happen?

Air enters your body through your nose or mouth, passes through the larynx, down the trachea, and into your lungs. In the lungs, air passes through a series of maze of smaller and smaller bronchial tubes until it finally reaches the alveoli.


Alveoli play a key role.

The alveoli are crucial, allowing the oxygen to pass from the air into the blood. Once there, transportation of oxygen around the body is possible.


How is Oxygen carried?

The blood carries oxygen in two ways. As it does not easily dissolve in water, only a little is carried in the blood plasma the rest combines with the haemoglobin in red blood cells and is transported thus. The key instrument for moving it around is of course your heart. Pumping around 70 times per minute, it keeps up a relentless beat, supplying your body with the oxygen and nutrients it needs 24/7.


What supports the heart?

Of course the heart cannot work without the network of blood vessels that weave to all areas of the body. Arteries are the blood vessels that carry the oxygen around the body, but rather than simply being passive pipes through which the blood passes, they actually have muscles in them when the heart pumps blood, they are elastic and expand, but as the heart relaxes, the muscles in the walls of the arteries contract to push the blood onwards.


2. Alveoli

alveoli respiratory system

Part of the respiratory system, these tiny alveoli have a key role in the movement of oxygen and carbon dioxide.


What is the role of the alveoli?

The final branches of the respiratory tree, alveoli are where oxygen from the air enters your blood, and carbon dioxide from your body is expelled back into the air.


How does the alveoli function?

Air enters the body through the nose or mouth, passes through the larynx, down the trachea, and into our lungs. Once it is in your lungs, air goes through a maze of smaller and smaller bronchial tubes until it reaches clusters of tiny sacs the alveoli. In appearance they are somewhat like bunches of grapes.


What is the size of your alveoli?

These alveoli are tiny, but your lungs are simply packed with them an estimated three hundred million per lung, all required to ensure that your body gets the oxygen it needs. Once it is in your lungs, the blood has to get into your blood. The alveoli are the primary gas exchange units of the lung. Quite simply, they are the point where the gas-blood barrier is thin enough to permit rapid gas exchange. To get into the blood, oxygen is diffused through the alveolar epithelium, a thin interstitial space, and the capillary endothelium. That is only half the process of course this process also has to work in reverse in order to allow CO2, a waste product carried by the blood, to be expelled back into the lungs, and thus out of the body when we exhale


3. Transportation of Carbon Dioxide (CO2)

carbon dioxide respiratory system

The transportation of CO2 is one of the key roles of the respiratory system, allowing the movement of waste products out of the body.


Why is the transport of CO2 important?

It is one of the primary functions of the cardiovascular system, and is crucial because it is an efficient way for the body to get rid of a waste product.


How is CO2 transported?

The main vehicle for the transport of CO2 is the blood. Our blood performs a number of functions which are vital for our survival. One of the main ones is bringing essentials, such as nutrients and oxygen, from central locations (e.g. lungs, small intestine) to the rest of the body. However it doesn’t just deliver the good stuff, it also takes away the bad stuff. In the same way that your car produces exhaust gases when the engine is running, when your cells function, they produce waste primarily carbon dioxide. If this remains in your cells, they cease to function properly, and will ultimately die. They therefore need a way to get this waste out of the cells, and ultimately, out of the body.


How does CO2 use Cells?

The system your body uses is elegant and simple in the same way that oxygen passes from the blood, through the walls of tiny capillaries and into the cells, it also allows carbon dioxide to pass from the cells, back into the blood. The blood then carries it around to the lungs, from where it can be breathed out of the body.


What are the risk factors of respiratory diseases?

• Smoking

• Age

• Second hand smoking

• Exposure to indoor air pollutants

• Exposure to outdoor air pollutants

• Allergens

• Unhealthy lifestyle

• Family history