Answer:
many alveoli are present in the lungs with a shape that further increases surface area. Thin walls - alveolar walls are one cell thick providing gases with a short diffusion distance. Moist walls - gases dissolve in the moisture helping them to pass across the gas exchange surface.
Explanation:
D. Increased porosity (allows extra oxygen and water)
They help the cell mutiply
Answer:
La causa exacta del consumo de drogas se desconoce. Los genes de una persona, la acción de las drogas, la presión de compañeros, el sufrimiento emocional, la ansiedad, la depresión y el estrés ambiental pueden ser todos factores intervinientes.
Explanation: