Respiratory System

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Respiratory System

We rarely think about breathing unless we’re out of breath. The act of breathing is part of the respiratory system, a complex process where air travels into and out of the lungs.

Respiration is slightly different, where exercise causes muscles to release energy in the form of glucose. Both systems are co-dependent, especially when you’re playing sport and inhaling greater quantities of oxygen.

  • Air is warmed, moistened and filtered as it travels through the mouth and nasal passages.
  • It then passes through the trachea and one of the two bronchi into one of the lungs.
  • After passing into the many bronchioles, it finally arrives into some of the millions of tiny sacs called alveoli.
  • This is where gas exchange takes place - oxygen passes out of the air into the blood, and carbon dioxide passes out of the blood into the air in the alveoli
  • Bronchi- "Singular" Bronhus.
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Respiratory System

When you inhale:

  • the intercostal muscles contract, expanding the ribcage.
  • the diaphragm contracts, pulling downwards to increase the volume of the chest.
  • pressure inside the chest is lowered and air is sucked into the lungs.

When you exhale:

  • theintercostal musclesrelax, the ribcage drops inwards and downwards
  • thediaphragmrelaxes, moving back upwards, decreasing the volume of the chest.
  • pressure inside the chest increases and air is forced out
  • Intercostal muscles - Muscle's between the ribs that aid breathing.
  • Diaphragm - a sheet of muscles below the lungs.
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Respiration - Is the release of energy from glucose in the muscles.

When the body is at rest this is aerobic respiration. As you exercise you breathe harder and deeper and the heart beats faster to get oxygen to the muscles.

Glucose + oxygen → energy + water + carbon dioxide

When exercising very hard, the heart cannot get enough oxygen to the muscles. Respiration then becomes anaerobic.

Glucose → energy + lactic acid

Aerobic- is exercising with oxygen

Anaerobic - is exercising without oxygen

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Inhaled and Exhaled Air.

Inhaledair contains:

  • more oxygen used to create energy
  • less carbon dioxide than…

Exhaledair which contains:

  • more carbon dioxide produced as a waste product of energy production
  • less oxygen as it has been used in respiration

Gas exchangetakes place by diffusion in the alveoli within the lungs. As a result the composition of inhaled and exhaled air is different.

Gas exchange

Gas% in inhaled air% in exhaled air Oxygen 21 16 Carbon dioxide 0.04 4 Nitrogen 79 79 NB These figures are approximate.

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