Explain how two phenotypically normal parents can give birth to a child with a genetic disorder.

Phenotype only tells you so much about the genotype.

Explanation:

Both the parents are carrying two different alleles. For example Gg. As long as you have one G, then you will not display the genetic disorder. If you have two gg, then you will display the genetic disorder. The parents are carriers by having a g. There was a 25% that their child would inherit a g from each of them and have gg as their genotype and a genetic disorder as their phenotype.

substitution is the answer in this case

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.