Answer:
DNA ligase
Explanation:
DNA replication is an enzyme mediated, 3-step process during which the DNA molecule produces a copy of itself. The 3 steps involved are as follows;
- initiation
- elongation
- termination
<em>Initiation </em>involves the unwinding of the double helix structure of the DNA using DNA helicase enzyme
<em>Elongation</em> involves binding of RNA primer to the DNA strands and addition of bases to the primer<em> </em>to elongate the new chains. Bases are added to the leading strand continuously while the lagging strand is replicated in short segments (okazaki segments).
<em>Termination</em> involves the unbinding of RNA primer and substitution of its bases by DNA bases. The Okazaki fragments are then joined together using the DNA ligase enzyme.
<em>The short, numerous segments of DNA observed in the mixture is the Okazaki fragments of the lagging strand. This is due to the absence of the enzyme involved in the joining of these fragments.</em>
Hence, the answer is DNA ligase.
Phytoplankton contribute positively in the oceanic ecosystem as they are a source of food for oceanic animals. Moreover, they remove carbondioxide from the carbon cycle and utilize it for the process of photosynthesis.
Answer:
B. there were more double crossovers in the progeny than would be expected based on probability
Explanation:
Crossing over or recombination can be defined as the exchange of genetic material between homologous chromosomes during meiosis. Moreover, the coefficient of coincidence is the number of double recombinants found in the progeny. The coefficient of coincidence can be estimated by the following equation:
Coefficient of coincidence (COC) = ADRF / EDRF
where ADRF = Actual Double Recombinant Frequency
and EDRF = Expected Double Recombinant Frequency
In the case above described, ADFR is higher than EDRF, and therefore COC will be higher than 1.
