Explain why we use the letters v and v to represent the alleles for height

Alleles are the alternative form of gene . When we talk about the allele we have one capital letter that is V here  and one is small letter that is v  here . V represent the dominant allele and the v represent the recessive allele. V will show the dominant phenotype in the individual and it should have one copy of the allele , and the v will show recessive phenotype in the particular individual.

water is a polar molecule. a chemical bond is a force of attraction between atoms or ions. bonds form when atoms share or transfer valence electrons. atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. so, false

explanation:

in h2o molecule, two water molecules are bonded by a hydrogen bond but the bond between two h - o bonds within a water molecule are covalent. the greater the electronegativity difference, the more ionic the bond is. bonds that are partly ionic are called polar covalent bonds. nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.