Respiratory System Flashcards

Respiratory System

Function

• Supplies oxygen to the body and removes carbon dioxide through cellular respiration. The chemical equation can be represented as: Oxygen \rightarrow Carbon Dioxide + Water

Main Processes

• Breathing: Physical process of inhalation and exhalation.
  • Inhalation: Taking oxygen from the air.
  • Exhalation: Removing carbon dioxide from the body.
• Gaseous Exchange: Exchange of oxygen and carbon dioxide through diffusion.
  • Inhaled oxygen diffuses through the walls of the alveoli into the blood.
  • Carbon dioxide diffuses from the blood into the alveoli and is exhaled.
• Cellular Respiration: Process where glucose is broken down inside cells by oxygen, releasing energy.
  • Oxygen is used, and carbon dioxide and water are produced.

Main Components

• Nose and Mouth: Outer openings.
  • Nostrils: Lead to nasal cavities.
  • Inhaled air is warmed, purified by fine hairs (cilia), and moistened by mucus in the nasal cavities.
• Trachea (Windpipe): Tube that enters the chest and allows air to flow through.
  • Kept open by cricoid cartilage.
  • Trachea branches into two smaller bronchial tubes called bronchi (singular: bronchus) that enter the lungs.
• Lungs: Main organ of the respiratory system.
  • Two spongy, elastic organs in the chest cavity.
  • External Structure:
    • Well-protected by the spine at the back, ribcage laterally, and breastbone in front.
    • Conical and pink-grey in color due to capillaries.
    • Separated by space where the heart is located.
  • Internal Structure:
    • Bronchi form bronchioles.
    • Bronchioles become smaller further into the lung.
    • Smaller bronchioles end in a small lung sac (infundibulum) consisting of alveoli (lung sacs).
    • The entire structure looks like a bunch of grapes.
    • Each alveolus has a very thin wall and is almost completely surrounded by blood flowing through a network of small blood vessels.
    • Approximately 200-300 million lung sacs (alveoli) in each lung.
• Diaphragm:
  • Dome-shaped muscular partition below the lungs.
  • Allows you to breathe.
    • When it contracts, it moves downwards, and your lungs fill up.
    • When it relaxes, it moves upwards and forces the air out of your lungs.
  • Most important muscle used for breathing.

Health Issues

• Asthma:
  • Caused by allergies, which narrows airways, leading to:
  • Symptoms: Wheezing, a tight chest, shortness of breath, and coughing.
  • Can be caused by genetics and environmental factors.
• Lung Cancer:
  • Cells in lungs grow out of control and form tumors.
  • Affects the lung's capability to supply oxygen to the blood.
  • Symptoms: Chest pains, shortage of breath, weight loss, and a chronic cough or wheezing.
• Bronchitis:
  • Swelling of the lining of the bronchi due to infection that causes coughing and makes getting air to the lungs difficult.
  • Airways become congested with mucus.
  • Symptoms include wheezing and shortness of breath.
  • Often caused by smoking or inhaling polluted air.
• Tuberculosis (TB):
  • Caused by bacteria and is contagious.
  • Bacteria are inhaled and contaminate the lungs, breaking down lung tissue.
  • Breathing effectiveness is reduced.
  • Irritation caused by bacteria causes coughing.