Answer:
A. These homologous structures indicate that these four organisms all share a common ancestor.
Explanation:
Homologous structures mean the organs will have similar structure, but not necessarily function (human arm vs whale's flipper). While analogous structures are similar in function but not structure (wings of an airplane vs wings of a bird). Since the question states that they are similar in skeletal structure, we know they must be homologous structures, thereby eliminating B and C. D is not a choice because the question does not provide anything about the order of evolution. Therefore the answer is A. These homologous structures indicate that these four organisms all share a common ancestor.
Answer:
Poriferans.
Explanation:
The evolution of the organisms has been occur from the simple organisms and leads to the evolution of the more complex organisms. This complexity arises due to the changing environment of the organisms.
The protozoans are the simplest organisms and all the other animal lineage has been derived from the porifera. The porifera are the cellular organisms that do not have tissue level of organization and simple physiological system. Later, diverse and complex organisms arise from the porifera.
Thus, the correct answer is option (1).
D. Made of ash and pieces of rock rich in silica.
Should be your answer!
Answer:
third and fourth trophic levels
Explanation:
