nose - nasal cavity - larynx - trachea - primary bronchus - secondary bronchi - tertiary bronchi - terminal bronchi oles - respiratory bronchioles - alveoli - alveolar sacs
the alveolar sacs contain the pulmonary capillaries. the actual gas exchange occur here by simple diffusion. O2 goes from the lungs into the O2 depleted RBC.
diffusion
Oxygen enters the pulmonary blood in the capillaries of the alveoli -- the air sacs of the lungs.
External respiration refers to the exchange of oxygen and carbon dioxide between the lungs and the blood in the pulmonary capillaries. This process allows for oxygen to be taken up by the blood and carbon dioxide to be removed from it.
carbon dioxide
Oxygen passes from the air sacs in the lungs to the blood in the capillaries, carbon dioxide passes the other way.
This process, from the alveoli in the lungs, to the pulmonary capillaries, is generally termed "respiration".
through pulmonary veins
The Capillaries transfers waste filled blood from the tissues into the Pulmonary circulation.capillariesTiny blood vessels that pass food and oxygen to cells and receive waste from cells.
Oxygen moves into the lungs to the alveoli in the lungs into capillaries into pulmonary veins to the heart then to arteries that go through the rest of the body.
It diffuses into the blood capillaries surrounding the alveoli.
Systemic Arteries carry oxygen rich blood (also called oxygenated blood). Pulmonary Arteries carry oxygen poor (deoxygenated) blood
External Nares (Nostrils) --> Nasal Cavity --> Inferior, Superior, & Middle Nasal Conchae --> Pharynx --> Larynx --> Trachea --> Primary Bronchi (Left & Right) --> Hilus --> Bronchioles --> Respiratory Bronchioles --> Alveolar Ducts --> Alveoli (the grape-like sacs) --> the the "spider web" of Pulmonary Capillaries.