In single-celled organisms such as protozoa,__________ is/are the mechanism(s)used to move gases into and out of the body.
A)vascular gills
B)active transport
C)vascular membranes
D)diffusion
E)costal ventilation

Question

Quizplus · Accepted Answer

In single-celled organisms such as protozoa, diffusion is the mechanism used to move gases into and out of the body. This is because gases move from an area of higher concentration to an area of lower concentration, and because single-celled organisms have a high surface area to volume ratio, gases can easily diffuse across their cell membranes. Vascular gills, active transport, vascular membranes, and costal ventilation are mechanisms used by more complex organisms.

In Single-Celled Organisms Such as Protozoa,__________ Is/are the Mechanism(s)used to Move