Answer: c) and b) are correct.
The brain is encased in a protective bony or cartilaginous housing in craniates.
The anterior end of the nerve cord is elaborated to form a brain in craniates.
Explanation: The craniates include the chordata with well-defined heads. This includes mammals, reptiles and fishes. So we can discard the other answers. Because most craniates have functional jaws, and the adults do not lose their chordate characteristics. The last one does not apply as a specific feature because the tunicate have neural crest but are not recognized as craniata.
Answer:
In an ecosystem, energy enters in the form of solar energy or light energy from sun. Solar energy is transformed into various other types of energies like kinetic energy, chemical energy, potential energy, etc; but it eventually leaves the ecosystem in the form of heat energy.
The answer to this question is D: Psychoactive. It is the world's most widely consumed psychoactive drug.
In order to produce an effective immune response within the body, the person must be injected with a dosage of a virus or bacteria, and for it to be allowed to grow in the person, which replicates just enough to stimulate a response from the immune system.
