Answer:
<h2>c. Division of these two groups occurred after the protostome developmental sequence appeared. </h2>
Explanation:
- Protosomes are such types of organisms in which the mouth part developed first during embryonic development.
- Those animals in which anus develop first are known as deuterostomes.
- This differentiation takes place during the embryonic development of the organisms.
- Since lophotrochozoan and Ecdysozoa both are protostomes animals and categorized on the basis of molecular evidence.
- Thus these two groups were formed after the appearance of the protostomes.
All the cells don't have all of the intracellular structures because each and every cell do not need each and every intracellular structure. The plant cells have chloroplasts because they need to convert the light energy into chemical energy via the process of photosynthesis, the animal cells, however, have no such need, therefore, the animal cells do not have chloroplasts. Also, the erythrocytes do not have the cellular organelles in them which are present in the other body cells, because there is no need for the cellular organelles in them. The large vacuoles in plant cells is also a great example. The plants need the vacuoles for the metabolic processes, while most animal cells have no need for them.
The correct answer is allele.
I hope I helped!
