Answer:
Type II cells
Explanation:
Type II alveolar cells are the round-shaped or cuboidal epithelial cells. These cells have a free surface with microvilli. The function of the type II alveolar cells is to secrete the alveolar fluid to keep the surface of the cells moist.
A mixture of phospholipids and lipoproteins is present in the alveolar fluid that serves as surfactant and reduces the surface tension of the alveolar fluid. The overall effect of the presence of surfactant in alveolar fluid is to protect the alveoli against collapsing during exhalation.
Because they have not been distrubed
Answer:
The correct answer is: lets the air get inside the lungs.
Explanation:
The process of ventilation, or breathing, consists of two parts: <u>inhaling and exhaling.</u>
Inhaling is the name of the process that is responsible for the air entering the body by the respiratory tract. Exhaling is the opposite, it lets the air out. Both are equally important since they allow the gas exchange necessary for the oxygenation of the blood.
When inhaling, the diaphragm and the external intercostal muscles contract. This pulls the ribcage upwards and outwards, which increases lung volume while decreasing the air pressure inside.
Answer:
A retrovirus is an RNA virus that is duplicated in a host cell using the reverse transcriptase enzyme to produce DNA from its RNA genome. The DNA is then incorporated into the host's genome by an integrase enzyme. The virus thereafter replicates as part of the host cell's DNA.
