• Breathing at depth

• Inhalation and exhalation

• Parts of respiratory system

• Main fuctions

• Process of breathing

Breathing at depth

Respiration is the sequence of events that results in the exchange of oxygen and carbon dioxide between the atmosphere and the body cells. Every 3 to 5 seconds, nerve impulses stimulate the breathing process, or ventilation, which moves air through a series of passages into and out of the lungs.

Parts of the Respiratory System

Your respiratory system includes your:

• Nose and nasal cavity
• Sinuses
• Mouth
• Throat (pharynx)
• Voice box (larynx)
• Windpipe (trachea)
• Diaphragm
• Lungs
• Bronchial tubes/bronchi
• Bronchioles
• Air sacs (alveoli)
• Capillaries

Typical breathing effort when breathing through a diving regulator

Pressure increases with the depth of water at the rate of about one atmosphere— slightly more than 100 kPa, or one bAr, for every 10 meters. Air breathed underwater by divers is at the ambient pressure of the surrounding water and this has a complex range of physiological and biochemical implications. If not properly managed, breathing compressed gasses underwater may lead to several diving disorders which include pulmonary barotrauma, decompression sickness, nitrogen narcosis, and oxygen toxicity. The effects of breathing gasses under pressure are further complicated by the use of one or more special gas mixtures.

 Process of breathing

When the lungs inhale, the diaphragm contracts and pulls downward.As a result, air rushes in and fills the lungs. The second phase is called expiration, or exhaling. When the lungs exhale, the diaphragm relaxes, and the volume of the thoracic cavity decreases, while the pressure within it increases.

Steps of breathing

• Your diaphragm moves down as it contracts. …
• Air rushes in through the nose and mouth and passes through the throat. …
• Air moves into your bronchi. …
• Air moves into your alveoli. …
• Carbon dioxide moves from the blood through the walls of capillaries and alveoli in order to be expelled by the lungs.

Inhalation and exhalation

When you inhale (breathe in), air enters your lungs and oxygen from the air moves from your lungs to your blood. At the same time, carbon dioxide, a waste gas, moves from your blood to the lungs and is exhaled (breathe out)

When you inhale (breathe in), air enters your lungs and oxygen from the air moves from your lungs to your blood. At the same time, carbon dioxide, a waste gas, moves from your blood to the lungs and is exhaled (breathe out).

Respiration & Functions

The lungs and respiratory system allow us to breathe. They bring oxygen into our bodies (called inspiration, or inhalation) and send carbon dioxide out (called expiration, or exhalation). This exchange of oxygen and carbon dioxide is called respiration.

The functions of the respiratory system include gas exchange, acid-base balance, phonation, pulmonary defense and metabolism, and the handling of bioactive materials.

Key facts about the respiratory system Table quiz
Upper respiratory tract	Nasal cavity, paranasal sinuses, pharynx and larynx above the vocal cords
Lower respiratory airways	Larynx below the vocal cords, trachea, bronchi, bronchioles and lungs
Functions	Upper respiratory tract: conduction, filtration, humidification and warming of inhaled air Lower respiratory tract: conduction and gas exchange

By Hamza ishfaq chief editor and CEO