The embryos of all animals undergo gastrulation, a dramatic reorganization of cells critical to formation of the animal body. do you understand all the terms associated with gastrulation?
the correct answer is a. inhale odor molecules into nasal cavity.
it is very true to make the function of the cell work well
the spicules are the thin and spiny structure that forms the skeleton of a sponge. the spicules provide the structural support and they are small needle-like in a shape. the spicules consist of calcium carbonate and silicon dioxide. it is found in many sponges of the skeleton, they are basically like crystals and they have a pointed and hard and sharp body. like animals, the sponges also posses some sort of skeleton which gives shapes to their body. the skeletal system of the sponge is like a needle or cluster in shape.