Respiratory System

RES

PIR

ATO

RY

SYS

TEM

(Called also respiratory apparatus, ventilator

system) is a

biological system

consisting of specific

organs and

structures used for the process of respiration

in an organism.

PART OF RESPIRAT

ORY SYSTEM Lungs

The lungs are the main organs of the

respiratory system. In the lungs oxygen is taken into

the body and carbon dioxide is breathed out. The

red blood cells are responsible for picking up the

oxygen in the lungs and carrying the oxygen

to all the body cells that need it.

The trachea is sometimes called the windpipe.

The trachea filters the air we breathe

and branches into the bronchi.

The bronchi are two air tubes that branch off of the

trachea and carry air directly into the lungs.

Breathing starts with a dome-shaped muscle at

the bottom of the lungs called the diaphragm when you

breathe in, the diaphragm contracts. When it

contracts it flattens out and pulls downward. This

movement enlarges the space that the lungs are

in. This larger space pulls air into the lungs.

As we breathe, oxygen enters the nose or mouth and passes the sinuses, which are hollow spaces in the skull. Sinuses help regulate the temperature and humidity of the air we breathe.

The trachea, also called the windpipe, filters the air that is inhaled, according to the American Lung Association. It branches into the bronchi, which are two tubes that carry air into each lung. The bronchial tubes are lined with tiny hairs called cilia. Cilia move back and forth, carrying mucus up and out. Mucus, a sticky fluid, collects dust, germs and other matter that has invaded the lungs. We expel mucus when we sneeze, cough, spit or swallow.

The bronchial tubes lead to the lobes of the lungs. The right lung has three lobes; the left lung has two, according to the American Lung Association. The left lung is smaller to allow room for

the heart, according to the National Heart, Lung and Blood Institute (NHLBI). Lobes are filled with small, spongy sacs called alveoli, and this is

where the exchange of oxygen and carbon dioxide occurs.

The alveolar walls are extremely thin (about 0.2 micrometers). These walls are composed of a single layer of tissues called epithelial cells and tiny blood vessels called pulmonary capillaries.

Blood passes through the capillaries. The pulmonary artery carries blood containing carbon dioxide to the air sacs, where the gas moves from the blood to the air, according to the NHLBI. Oxygenated blood goes to the heart through the pulmonary vein, and the heart pumps it throughout the body.

The diaphragm, a dome-shaped muscle at the bottom of the lungs, controls breathing and separates the chest cavity from the abdominal cavity, the American Lung Association noted. When a breath it taken, it flattens out and pulls forward, making more space for the lungs. During exhalation, the diaphragm expands and forces air out.

Nostrils are involved in air intake, they bring air into the

nose, where air is warmed and humidified. The tiny

hairs called

cilia filters out dust and other particles

present in the air and protects the nasal passage and

other regions of the respiratory tract.

What Is the Function of the Respiratory System?

Each part of your body works together seamlessly to create the breathing that you need to survive. Here are the functions of the respiratory system and how each organ works in tandem with the rest to create seamless, effortless breathing.

1. Breathing-Inhalation and Exhalation

The Act of Breathing:

When you inhale air through your nose or mouth, it goes straight to the trachea, or windpipe. Just below that, the trachea divided into several tubes known as bronchial tubes. The air you breathe goes into these, then into bronchioles in the lungs, which are even smaller tubes. The air then fills little sacs in the lungs, called alveoli. There are over 300 million of these in the typical human body.

The alveoli are surrounded by tiny blood vessels. These blood vessels suck the oxygen out of the air you have just taken in and send it to the blood, where it goes to the heart, where it is then pumped around your body to give your cells the oxygen they need.

As this happens, carbon dioxide is formed. The blood carries that back to your lungs, where the process reverses. When you breathe out, you are exhaling the carbon dioxide that was created inside your body. With each breath, the process continues.

Role of Diaphragm in Breathing:

One of the most important components of your body is the diaphragm. This is a large muscle shaped like a dome that sits right underneath your lungs. When you take a breath, the diaphragm pushes downward, creating a vacuum that then sucks the air into your lungs. When you exhale, the diaphragm pushes upward and outward, forcing the carbon dioxide from your body. An injury to the diaphragm can make it difficult to breathe, even if there is nothing wrong with the rest of your respiratory system.

2. Clearing the Air

The respiratory system also plays defense for you. The nose is filled with tiny hairs that filter out large particles. These hairs are also found among the air passages, where they move back and forth to “sweep” the air clean. The mucus produced in your respiratory system works to trap foreign invaders, such as bacteria, and prevent it from going deeper into your body. Finally, the things that do get past these defense systems can be coughed up from the lungs and expelled.

There are 3 major parts of the respiratory system: the airway, the lungs, and the muscles of respiration. The airway, which includes the nose, mouth, pharynx, larynx, trachea, bronchi, and

bronchioles, carries air between the lungs and the body's exterior.