B) Oxygen may not have been able to accumulate in the atmosphere
The offsprings or children would be very similar to their parents.
Cross over involves the exchange of chromosomes segments between non-sister chromatids during the process of meiosis. It creates new combinations of genes in the gametes that are not found in either parent, a factor that brings about genetic variation or genetic diversity among individuals. Therefore, without crossover offsprings would be genetic similar with their parents.
<span>DNA, cell membrane, ribosomes, and membrane-bound</span>
The 2 correct statements are "DNA uses deoxyribose and RNA uses ribose" (indicated by the first letter of each) and "DNA has thymine and RNA has uracil" (uracil is not found in DNA and thymine is not found in RNA.)