Breathing and Exchange of Gasses

Respiratory organs in animals,humans system

  1. Protozoans (Amoeba, Paramecium) respires through plasmalemma and pellicle.
  2. Sponges use plasma membrane of each cell to respire.
  3. Hydra like cnidarians respires through body wall and ctenophora too.
  4. Parasites of Flat worms and rounds worms undergo anaerobic respiration.
  5. Annelids undergo breathing through its body wall.
  6. Crayfish and prawn possess gills [branchial respiration]
  7. Tracheal respiration is present in insects, centipede, millipede, ticks and peripatus.
  8. Scorpions, spiders uses book lungs and Limulus (king crap) uses book gills.
  9. Hemi chordates, Urochordata and Cephalochordata involves pharyngeal wall to breathe.
  10. Gills arise in Cyclostomes and Fishes.
  11. Amphibians like frogs do breathe using skin, lungs, and buccopharyngeal cavity.
  12. Reptiles, Birds and Mammals consists of lungs for gaseous exchange.
  13. Human respiratory system is as follows. External nostrils → Nasal cavities → Internal Nares → Pharynx → larynx (glottis, epiglottis, Hyoid bone, Vocal cords) → Trachae (wind pipe) → Lungs (pulmones) → Bronchus → Bronchioles → Alveolar ducts → Alveoli (Acini).
  14. Vocal cords are made up of non-keratinized stratified squamous epithelium.
  15. Lower pair of vocal cords are true vocal cords.
  16. Glottis is covered by epiglottis (cartilaginous flap) that prevents food entry into windpipe.
  17. Pharynx is made up of stratified squamous and larynx is made up of ciliated columnar epithelium.
  18. Trachea contains rings of hyaline cartilage (incomplete at posterior part) to prevent the collapse of windpipe during inspiration.
  19. Left lung contains 2 lobes and right lung comprises 3 lobes.
  20. Below the lung, there exist diaphragm and left lung possess a cardiac notch, mediastinum, where heart is located.
  21. Lungs are located in thoracic cavity covered by pleural membrane supported by pleural fluid.
  22. Three types of bronchus are principal/primary, secondary/lobal and tertiary/segmental bronchus that possess hyaline cartilage.
  23. Internally bronchus divides into bronchioles which is of 3 types (i) Lobular (ii) Terminal and (iii) Respiratory.
  24. Alveolar epithelium and capillary endothelium are the tissue characteristic in lungs.
  25. A surfactant layer made of lecithin is present in alveolar membrane to prevent the foam formation.

Watch this video for the topic Respiratory organs in animals,humans system from 0:47 to 40:48

Disclaimer: may from time to time provide links to third party Internet sites under their respective fair use policy and it may from time to time provide materials from such third parties on this website. These third party sites and any third party materials are provided for viewers convenience and for non-commercial educational purpose only. Compete does not operate or control in any respect any information, products or services available on these third party sites. makes no representations whatsoever concerning the content of these sites and the fact that has provided a link to such sites is NOT an endorsement, authorization, sponsorship, or affiliation by with respect to such sites, its services, the products displayed, its owners, or its providers.