<span>a. Acoelomates. Flatworm is a type of acoelomate animal; they have no body cavity or ceolom but they have </span>mesenchyme in their body cavity that surrounds the gut and organs in one solid body.
As altitude increases, temperature decreases. What is the relationship between atmospheric pressure and the density of gas particles in an area of decreasing pressure? As air pressure in an area decreases, the density of the gas particles in that area decreases.
