The distinction between protostomes and deuterostomes is based on differences in their embryological development. Protostomes develop their oral end from their first developmental opening, while deuterostomes have their oral end develop from the second opening on the dorsal surface.
Answer:
most likely silt.
Explanation:
its not humus cause humus is sticky. its not sand cause when sand is wet its very gritty and hard. its not gravel because gravel is gritty. hope this helped
<span>The metabolic activity of a specific region of the living rat brain can be revealed by measurement of Fos protein concentration.
c-Fos is a proto-oncogene that is the homolog of the retroviral oncogene v-fos. It was first discovered in rat fibroblasts as the transforming gene of the FBJ MSV.</span>
Ok I think its small polar molecules but I could be wrong.
The red blood cels are pushed through both systems and works as a avocet to the send signals that the heart is overworked and cant push enough blood to the need breathing