Because it can lose or gain an electron. For example, it becomes a part of a molecule because it can form bonds
A fertilized egg is called a zygote until it divides into 16 cells, forming a ball-shaped structure called a morula. The events during the zygote stage involve the integration of both parents' DNA into the cell nucleus and the beginning of rapid cell division, or cleavage.
Let 'C' denote the dominant trait of eye-crossing and 'c' denote the recessive trait of not being able to cross the eyes. The genotype of the father is heterozygous dominant for the trait of eye-crossing. This is denoted by 'Cc'. The mother is homozygous recessive for the trait of eye-crossing, denoted by 'cc'. The mating between the two will result in following genotypes: two of 'Cc' and two of 'cc'. Therefore the probability that the child will be able to cross his or her eyes is 0.5 or 50%.
Hi there!
<u>Electronegativity</u> is the concept of how likely an atom is to attract the shared molecules in one of these bonds to itself. We know the molecule water is made up of two hydrogens and one oxygen. The electronegativity of hydrogen is 2.2, and oxygen 3.4. An <u>ionic bond</u> needs at least a difference in electronegativity of 1.6. As the difference is less than that, we can say that water is a covalent molecule. This then wipes out choice B, because it is not ionic, and C, as we have seen it is actually covalent.
Now, we can see the difference in electronegativity between oxygen and hydrogen is still 1.2. This means that while it is not at the point for there to be an ionic bond, there is still a difference in attraction, where the electrons will tend to favor the oxygen more and 'hang around it' more. As electrons are <u>negatively charged</u><em><u>,</u></em> this means that the oxygen will gain a slightly negative charge. This then makes the molecule polar, because it now has a charge within the molecule. This means we have our answer, choice D.
In terms of hydrophobic molecules - they tend to be ones without a charge. (If you're interested in this kind of stuff, I'd search hydrophobic up, and possibly also look into hydrogen bonds).
Hope this helps! Feel free to ask me any other questions you have about this specific problem.
