Respiratory System

• Stages of Respiration


  • Breathing
  • External Respiration
  • Internal Respiration
  • Cellular Respiration
• Breathing


  • Inspiration
  • Expiration
• External Respiration


  • Exchange of oxygen and carbon dioxide between the atmosphere and blood in the alveoli
• Internal Respiration


  • Exchange of oxygen and carbon dioxide between the blood and body tissue cells
• Cellular Respiration


  • Process by which cells convert glucose and oxygen into water, carbon dioxide, and ATP (adenosine triphosphate)
• Requirements for efficient gas exchange

  • Large surface area
  • Constant ventilation (breathing) to maintain diffusion gradients
  • Moist, warm environment
• Erythrocytes (red blood cells) are important for efficient gas exchange
• Inspiration breathing


  Movement of the air from the atmosphere into the lungs
• Expiration breathing


  Movement of the air from the lungs to the atmosphere
• Nasal Cavity


  Lined with tiny hairs called cilia and a thick mucous membrane
• Cilia filters out debris in the air and sweeps it toward the pharynx (throat)
• The moist mucous membrane traps debris, and helps moisten and warm the air.
• Always best to breathe through the nose since the air is cleaned, moistened and warmed for efficient gas exchange
• Pharynx functions


  • Acts as a passage for both food and air
  • Opens into both the trachea (windpipe) and the esophagus
• The epiglottis is a flap-like structure which prevents food or liquids from entering the trachea during swallowing
• Larynx


  Connects the pharynx with the trachea
• Vocal cords


  Produce sound as air is forced from the lungs to the pharynx
• Bacterial or viral infections of the cords cause laryngitis
• Inflammation of the vocal cords

  Makes talking painful and causes loss of voice
• Where are vocal cords found?

  Larynx
• Functions of the Respiratory System?


  • Bring oxygen into the body and remove carbon dioxide.
  • Allows for exchange of the gases between the atmosphere and body cells.
• The two exchange sites

  1.At the alveoli of the lungs

  2.At the body cells
• Stages of Respiration

  1.Breathing

  2.External respiration

  3.Internal respiration

  4.Cellular respiration
• Inspiration


  Movement of air from the atmosphere into the lunge.
• Expiration


  Movement of air from lungs to the atmosphere.
• External Inspiration 


  • The exchange if oxygen and carbon dioxide between the air and the blood
  • Happens in the alveoli
• Internal Respiration

  • The exchange of oxygen and carbon dioxide between the body’s tissue cells and the blood
  • Happens in the body cells
• Requirements for External Respiration

  1.Large surface area for efficient gas exchange

  2.Moist, warm environment for efficient gas exchange

  3.Constant ventilation (breathing) maintain diffusion gradients
• Movement of Air

  Nostril -> Nasal Cavity -> Pharynx -> Larynx -> Trachea -> Bronchi -> Bronchioles -> Alveoli -> Circulatory System
• Nasal Cavity

  • Lined with tiny hairs called cilia and a thick mucous membrane
  • Cilia filters out debris in the air and sweeps it towards the pharynx (throat)
  • The moist mucous membrane traps debris and helps to moisten and warm the air
• Pharynx


  The pharynx acts as a passage for both food and air

  • The pharynx opens into both the trachea (windpipe) and the esophagus.
• Epiglottis


  A flap-like structure which prevents food or liquids from entering the trachea during swallowing.
• Larynx

  The larynx (voice box) connects the pharynx with the trachea.

  • The vocal cords are found within the larynx
  • The vocal cords produce sounds as air is forced from the lungs to the pharynx
  • Bacterial or viral infection of the vocal cords causes laryngitis. inflammation makes talking painful and causes loss of voice
• Trachea and Branchi


  Passageway for air between lungs and pharynx
• Trachea and Branchi


  • Composed of circular cartilage rings separated by muscle tissue
  • Design ensures passageways always stay open
• Bronchioles


  Tiny narrow tubes inside the lungs for air
• Bronchioles


  • Composed of smooth muscle (no cartilage rings)
• Tubes lining the respiratory system

  • Trachea
  • Branchi
  • Bronchioles
• Tubes lining the respiratory system

  • Lined with cilia and mucus to trap dirt and bacteria which is swept up to the back of the throat
• Alveoli


  Tiny air sacs in the lungs where gas exchange occurs