<h2><u>Answer</u> :</h2>
The correct option is A. If a dominant allele is present, the recessive allele won’t be seen.
The dominant allele is the one which appear, and the recessive one isn't shown.
For example - If a person has 2 alleles of eye colour as B ( black ) and b ( brown ), in which black is dominant and the brown one is recessive, then the person will have black eye colour because only dominant allele shows its characteristics.
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Deserts, savannas, and grasslands.
Sister chromatids are two identical copies of Chromosome that is formed by the replication of a single chromosome.
This copies are formed during mitosis. Later on, these two sisters chromatids will grown into two different Cells
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Answer:
c. If the double helix were unwound, each nucleotide along the two parent strands would form a hydrogen bond with its complementary nucleotide.
Explanation:
According to the Watson-Crick model, two DNA strands are held together by complementary base pairing wherein each nucleotide of one DNA strand forms hydrogen bonds with its complementary nucleotide present in the other strand. During DNA replication, two DNA strands are separated by the action of helicases enzymes.
The separated DNA strands serve as a template for DNA replication. Here, each nucleotide of the template DNA strand binds to its complementary nucleotide by hydrogen bonds. For example, adenine of the template strand forms two hydrogen bonds with thymine while guanine forms three hydrogen bonds with cytosine.