Answer:
A) One band of intermediate density and one band of heavy density.
Explanation:
According to semi conservative model of replication the two DNA strands separate during replication such that the new DNA molecule has one parental strand and one new strand. In this experiment, originally E.Coli cells were grown in 14N medium so all the DNA strands had 14N. When the medium was changed to 15N, only 15N would be available to the cells for replication.
After first round of replication all DNA molecules would be of intermediate density as one strand would be old 14N strand and another would be new 15N strand. After second round of replication 15N strand would be formed from both 14N strand and 15N strand. So, one band will be formed of intermediate density (14N-15N) and another would be of heavier density (15N-15N).
“Fat must be broken down into fatty acids before being
converted to glucose” prohibits lipids from being a readily available energy
source.
Lipids<span> are a
group of naturally occurring molecules that include fats, waxes, sterols,
fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides,
diglycerides, triglycerides, phospholipids, and others.</span>
The correct answer between all
the choices given is the first choice or letter A. I am hoping that this answer
has satisfied your query and it will be able to help you in your endeavor, and
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