All of the following are traits of echinoderms except
a. five-part radial symmetry.
b. a pair of antennae.
c. tube feet.
d. an internal skeleton.

Fossils can only be formed when? if mud, silt or tar is in the area to preserve the fossil ierosion does not occur and allows the fossil to form oxygen and microorganisms cannot decay the bones the area is dry and does not contain mud or silt

14. which of the following codons code for threonine? a. ucg b. ugu c. cga d. aca

1. which of the following transport mechanisms utilizes energy? a. osmosis b. diffusion c. facilitated diffusion d. endocytosis