The first one is the Primary Bronchi
No, the trachea is not in the lower respiratory tract. It is part of the upper respiratory tract, connecting the larynx to the bronchi in the chest.
the lungs is the basic unit structure of the human respiratory system
no
the larynx
it consists of two parts
Nose
Medulla Oblongata
You DO find a respiratory structure in each segment of the earthworm. An earthworm uses its skin as the respiratory structure. Oxygen in the air dissolves in the moisture and mucus on the skin then diffuses into blood capillaries close to the skin to be transported to the rest of the body.
That's the primary structure.
ALVEOLI
The sequence of amino acids joined together forms a protein's primary structure. This linear sequence determines the protein's shape, function, and interactions with other molecules. It is defined by the mRNA template during protein synthesis.