Answer:
<em>The correct option is B. Alleles</em>
Explanation:
The punnet square can be described as a diagram which shows the outcomes of a cross. A punnet square will help us know what will be the probability for a particular trait to occur in the offsprings.
Genes might have the same or different alleles. If the alleles for a gene are similar in an organism, the organism is said to be homozygous for the trait. If the alleles are different, then the organism is termed as heterozygous.
A dominant allele is the one which which suppresses the effect of the recessive allele. A recessive allele gets masked by a dominant allele.
It is called THERAPEUTIC INDEX. Therapeutic index is the comparison of the amount of a particular drug that causes the desired therapeutic effects and the amount that causes toxicity. The index can be low or high. A drug with a low therapeutic index will require only a small increase in dose to produce toxic effects in users.
The function of the cell membrane is to protect the cell from any outer surroundings that could be harmful to it.
Terrestrial planet.
Terrestrial brings like us and animals live whereas as others don't satisfy any life.