Respiratory and skeleton system

• Gas exchange


  Exchange of gases can occur in different animals using a variety of respiratory organs
• Respiratory system


  Organs that allow gas exchange
• Insects


  • Have a tracheal system that exchange gases from the external environment through openings called spiracles
• Frogs


  • Exchange of gases occurs through their skin and lungs surface
• Birds


  • Use air sacs and lungs to exchange gases
• Aquatic organisms


  • Have gills to allow gas exchange between blood and water
• Mammals


  • Gas exchange process occurs in the alveoli in the lungs
• Animals, whether vertebrate or invertebrate, have evolved skeletal and muscular systems that give them form and enable them to move
• Skeletal system


  Necessary to support the body, protect the internal organs, and allow for the movement of an organism
• Skeleton designs

  • Hydrostatic skeleton
  • Exoskeleton
  • Endoskeleton
• Hydrostatic skeleton


  • A structure found in many ectothermic organisms and soft-bodied animals consisting of the coelom, a fluid-filled cavity, surrounded by muscles
• Exoskeleton


  • An external skeleton that supports and protects an animal's body, in contrast to the internal skeleton (endoskeleton) of a human
• Endoskeleton


  • A structure that holds an animal from inside
• Trachea


  A tube about 10 to 12 cm long and 2 cm wide, with a wall stiffened by 16 to 20 characteristic horseshoe-shaped, incomplete cartilage rings that open toward the back and are embedded in a dense connective tissue
• Stem bronchi


  The two bronchi that the trachea divides into, one for the left and one for the right lung
• Right main bronchus


  • Has a larger diameter, is oriented more vertically, and is shorter than the left main bronchus
• Airway branching pattern


  Follows the rules of irregular dichotomy, where the daughter branches may differ greatly in length and diameter
• Bronchioles


  Have goblet cells completely replaced by Clara cells, a different type of secretory cell
• Mucus layer


  Covers the epithelium
• Bronchiole walls


  Gain stability from their structural integration into the gas-exchanging tissues, as they lack cartilage
• Alveolar ducts


  Consist of alveoli so densely packed along the airway that an airway wall proper is missing
• Alveolar sacs


  The final generations of the airway tree, ending blindly
• protect the lower respiratory tract from aspirating food into the trachea while breathing.

  Larynx
• deliver air to a diffuse network of around 300 million alveoli in the lungs

  Bronchioles