The answer is D. The natural selection is a theory which illustrates the gradual process of evolution in the population due to the change of environment. The key point is the mutation (variation) exists in the population before the environment changing. For C, if the environment does not change, though the adaptation is useful to environment, it will not be selected. Because the organisms without the adaptation will not die.
Answer:
There should be 10% thymine
Explanation:
DNA bases come in specific pairs. Guanine pairs up with cytosine and adenine pairs up with Thymine.
According to the problem the DNA sample was 40% cytosine and 40% guanine, so this is correct, there are equal amounts of cytosine and guanine. Now Thymine needs to have equal amounts as adenine, but adenine only has 10%.
If we match up the amount of adenine to thymine, we would have 15% adenine and 15% thymine, but that would excede 100%. So you need to match the thymine to adenine.
10% adenine + 10 % thymine + 40% cytosine + 40% guanine = 100%
People believed that zebras were white animals with black stripes, since some zebras have white underbellies. Embryological evidence, however, shows that the animal's background color is black and the white stripes and bellies are additions.
Reflected light obeys the law of reflection, that the angle of reflection equals the angle of incidence. For objects such as mirrors, with surfaces so smooth that any hills or valleys on the surface are smaller than the wavelength of light, the law of reflection applies on a large scale.
