I think it’s A... not sure! Because you have no A so maybe A
Answer:
a. most genes encode one polypeptide and can be operationally defined by the complementation test
Explanation:
Genes are the stretch of DNA that code for specific polypeptides. In general, one gene codes for the only polypeptide.
Genes are defined by complementation tests which in turn tell if two mutations have occurred in the alleles of the same gene or different gene.
For the purpose, an organism with the homozygous genotype for one recessive mutation is crossed with an organism having the homozygous recessive genotype for another mutation.
If the two mutations are in the same gene, the progeny would show the mutant phenotype. On the other hand, if two mutations are in different genes, the progeny would exhibit normal phenotype.
Answer:
During DNA replication each parental DNA strand serves as a template to a new complementary strand. DNA polymerase is the main enzyme responsible for this process, it catalyzes the addition of nucleotides to form the new DNA chain.
The complementary nature of the DNA strands, presents a difficulty for DNA replication: DNA polymerase catalyzes the polymerization of DNA only in the 5’ to3’ -in the leading DNA strand. Thus, the opposite DNA strand, the lagging strand, faced an obstacle that is solved by the Okazaki small fragments. The primase enzyme synthesizes small RNA fragments complementary to the lagging DNA strand. These RNA fragments serve as primers for the DNA polymerase. To remove this RNA primers and form a continuous complementary lagging strand, RNase H and DNAse ligase will further cut and join the DNA again.
DNA polymerase has a higher processivity than primase, if processivity is the average number of nucleotides that it is capable to continuously add to the template strand. Primase dissociates from the template often during DNA replication as it has to constantly add new RNA primers to the strand.
D. At the center of the mid-ocean ridge. because it has to be above ground
