The human respiratory system is a complex network of organs and tissues that enables us to breathe. It includes the airways, lungs, blood vessels, and muscles facilitating lung function. Oxygen is vital for our body to work properly, and carbon dioxide is a waste product that needs to be removed. The respiratory system makes sure we get enough oxygen and get rid of carbon dioxide to keep our body healthy.

Anatomy

Anatomically, the respiratory tract can be divided into two parts: the upper respiratory tract, which includes the nose, pharynx, and larynx, and the lower respiratory tract, which consists of the trachea and lungs.

Nose: Air enters the respiratory system through the nose. The nose is lined with tiny hairs called cilia and mucus-producing cells that help filter, warm, and moisten the air before it reaches the lungs.

Pharynx: The pharynx is a tubular passage that connects the back of the nose and mouth to the larynx and esophagus. It is a common passage for air as well as food. Its essential function is to prevent food particles from entering the windpipe. The epiglottis, an elastic cartilage, acts as a valve between the larynx and the esophagus by allowing air into the lungs and food in the gastrointestinal tract.

Larynx: The larynx, also known as the voice box, is a hollow organ that enables you to produce sounds and speak as air flows in and out.

Trachea: The trachea, or windpipe, is a tube that connects the larynx to the bronchi. It is supported by cartilage rings and lined with cilia and mucus-producing cells that help remove debris and protect the lungs.

Bronchi: The trachea divides into two bronchi, one leading to each lung. The bronchi further divide into smaller branches called bronchioles.

Lungs: The lungs are in the chest, protected by a rib cage. Lungs are divided into lobes (three on the right, two on the left) and are enclosed by a thin membrane called the pleura. The bronchioles branch out into tiny air sacs called alveoli, surrounded by a dense network of blood vessels. Alveoli is the place where the exchange of oxygen and carbon dioxide occurs. 

The main muscles involved in breathing are the diaphragm and the muscles between the ribs (intercostal muscles). These muscles work together to create a pumping motion that helps move air in and out of the lungs

Functions

• Gas Exchange: Gas exchange in the lungs is the process where oxygen from the inhaled air enters the bloodstream, while carbon dioxide, a waste product, is removed from the bloodstream and exhaled. This exchange occurs in the tiny air sacs called alveoli, which are surrounded by blood vessels called capillaries. The thin walls of the alveoli allow oxygen to pass into the bloodstream and carbon dioxide to diffuse out. This vital process ensures that our body receives oxygen for energy production and eliminates carbon dioxide, maintaining a healthy balance of gases in our body.
• The larynx and vocal cords within it play a crucial role in speech and vocalization.
• Protecting your body from harmful substances. This is done by coughing, sneezing, filtering, or swallowing them.
• Supporting a sense of smell