It doubles, so the answer is 8 chromosomes.
Answer:
Background. Scientists measure a variety of properties to determine water quality. These include temperature, acidity (pH), dissolved solids (specific conductance), particulate matter (turbidity), dissolved oxygen, hardness and suspended sediment. Each reveals something different about the health of a water body.
Explanation:
DNA being placed with DNA polymerase and nucleotides and resulting in new copies is not an opinion or inference because the fact is, new more DNA was found in the test tube after adding the enzymes and nucleotides than before the addition. DNA sequencing of the new copies would have shown that the sequences of the new DNA are identical to the original DNA that was first placed in the test tube. Also, other experiments would have shown that adding other different kinds of molecules or enzymes does not, in fact, produce new strands of the original DNA, nor should it be able replicate the DNA at all.
Answer:
The correct option is A. they evolved from land mammals.
Explanation:
Evolution can be described as a process through which organisms in a species change over a period of time due to the natural selection of the environment. Those organisms that have many similarities in their functions or structures are considered closer to one another and have the same common ancestors.
The properties mentioned in the question about cetaceans resembles the properties of land mammals. For example, cetaceans lack gills and breathe air. Land mammals also do not have gills and need to respire for living. The cetaceans have fin bones which are similar to the limb bones in the land mammals. Hence, these observations show that cetaceas have evolved from land mammals.
