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Human Respiratory System

Human Respiratory System is a network of organs and tissues that helps us breathe. The primary function of this system is to introduce oxygen into the body and expel carbon dioxide from the body.

Diagram of Human Respiratory System

Human Respiratory System

Respiratory System Parts

Let us have a detailed look at the different parts of the respiratory system and their functions.

  • Nose: Humans have exterior nostrils, which are divided by a framework of a cartilaginous structure called the septum. This is the structure that separates the right nostril from the left nostril. Tiny hair follicles that cover the interior lining of nostrils act as the body’s first line of defense against foreign pathogens. And they provide additional humidity for inhaled air.
  • Larynx: It is found in front of the neck and is responsible for vocals as well as aiding respiration. Hence, it is also informally called the voice box. When food is swallowed, a flap called the epiglottis folds over the top of the windpipe and prevents food from entering the larynx.
  • Pharynx: It is a common passage for air as well as food. It functions by preventing the entry of food particles into the windpipe. The epiglottis is elastic cartilage, which serves as a switch between the larynx and the esophagus by allowing the passage of air into the lungs, and food in the gastrointestinal tract.
  • Trachea: The trachea or the windpipe rises below the larynx and moves down to the neck. The walls of the trachea comprise C-shaped cartilaginous rings which give hardness to the trachea and maintain it by completely expanding. The trachea extends further down into the breastbone and splits into two bronchi, one for each lung.
  • Bronchi: The trachea splits into two tubes called the bronchi, which enter each lung individually. The bronchi divide into secondary and tertiary bronchioles, and it further branches out into small air-sacs called the alveoli. The alveoli are single-celled sacs of air with thin walls. It facilitates the exchange of oxygen and carbon dioxide molecules into or away from the bloodstream.
  • Lungs: Lungs are the primary organs of respiration in humans. They are located on either side of the heart, in the thoracic cavity of the chest. Anatomically, the lungs are spongy organs with an estimated total surface area between 50 to 75 sq meters. The primary function of the lungs is to facilitate the exchange of gases between the blood and the air. The right lung is quite bigger and heavier than the left lung.

Respiratory System Functions

The respiratory system function is a very important metabolic process in our body that plays a crucial role in all living beings.

  • Olfaction or Smelling.
  • Inhalation and Exhalation.
  • Exchange of Gasses Between Lungs and Bloodstream.
  • Exchange of Gasses Between Bloodstream and Body Tissues.
  • The Vibration of the Vocal Cords.