Echinoderm is the name given to a member of the phylum Echinodermata. They have radial symmetry and this includes sea urchins, sand dollars, sea stars and sea cucumbers. It is suggested that they are related to the chordates which is the answer.
Answer:
D, The white blood cells of sick people may not be able to efficiently handle the weakened or dead form of the pathogen.
Explanation:
Vaccinations are essentially just weak diseases we use to create antibodies so the body can protect itself from the full disease. If it sees it once, it can defend itself, is the theory. This is choice D.
- Why not A: The weakened form will be attacked by the immune system, but maybe not enough, because the person is so sick that the immune system is busy elsewhere.
- Why not B: The medication is not what combines with the vaccine to cause problems. It is the body being overworked.
- Why not C: The digestive system isn't the issue. You don't eat diseases.
If I recall correctly, I was taught:
The particles in the air (dust, smoke, etc.) increase in density the farther you look. Causing a "fog" effect as you look across large distances. Including shore to shore of an ocean.