Respiratory System

Breathing and respiration are essential processes that allow the body to take in oxygen and release carbon dioxide. Breathing refers to the physical act of inhaling and exhaling air, while respiration is the chemical process by which cells use oxygen to produce energy. Together, these processes ensure that the body functions efficiently and remains alive.

The lungs are a pair of soft, spongy organs located in the chest on either side of the heart. They are protected by the rib cage and separated by the mediastinum. Each lung is divided into lobes, with the right lung having three lobes and the left lung having two. Inside the lungs are millions of tiny air sacs called alveoli, which are surrounded by blood vessels and are essential for gas exchange.

Flow of Respiratory System

Step & Organ	Function
1. Nose / Nasal Cavity	Filters air with hairs and mucus Warms and moistens incoming air
2. Pharynx (Throat)	Passage for air from nose to larynx Shared pathway with digestive system
3. Larynx (Voice Box)	Produces sound Protects airway during swallowing
4. Trachea (Windpipe)	Transports air to lungs Supported by cartilage rings
5. Bronchi	Two main branches into lungs Carry air deeper into lungs
6. Bronchioles	Smaller air passages Control airflow distribution
7. Alveoli	Site of gas exchange Oxygen enters blood Carbon dioxide leaves blood
8. Lungs	Contain bronchi, bronchioles, and alveoli Main organs of breathing
9. Diaphragm	Muscle that controls breathing Contracts to inhale, relaxes to exhale