Sickle-cell disease is common in tropical and sub-tropical regions because being a carrier, carrying a single sickle-cell mutation (sickle cell trait), affords some resistance to malaria.
The substance that is coded for by a length of DNA is base. The correct option is A.
<h3>What is a base?</h3>
Nucleobases, also known as nitrogenous bases or simply bases, are nitrogen-containing biological compounds that form nucleosides, which are then components of nucleotides, all of which are the basic building blocks of nucleic acids.
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The substance that is coded for by a length of DNA is base.
Thus, the correct option is A.
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Answer:
Energy
Explanation:
There are many different store and levels of energy which balance the mass so thats correct
Answer:
B) Polymerases can only synthesize in the 5' to 3' direction
Explanation:
The leading strand's directionality is 3' to 5', so polymerase has no problem with replicating this one. But the lagging strand has the opposite directionality, so the polymerase must work in the opposite direction of the replication fork.In consequence, the replication process undergoes periodic breaks, and the enzymes have to stop and start again while helicase separates both strands, resulting in the polymerization of okazaki fragments.