Tutor profile: Ossama S.

Why does electronegativity increase as you move from left to right on the periodic table?

Electronegativity is caused by the electrostatic forces within the atom. This is mainly contributed to the need for a full valance shell at given energy levels and the number of protons in the nucleus. As you move from left to right across the table, you are increasing the number of protons in the nucleus while maintaining the same shell energy level. There is more positive forces within the nucleus that help attract the electronegative electrons closer to the nucleus and explains why Fluorine is more electronegative than nitrogen. They occupy the same energy level but fluorine has more protons that allow it have a greater attractive force on the electron cloud.

When performing pedigree analysis, what determines a genetic trait to be sex-linked as opposed to autosomal?

In the case of Humans, we have 23 pairs of chromosomes. 22 pairs are autosomal, and the 1 pair are known as sex chromosomes since these help encode for genes that will determine the individual's sex., XY for male and XX for female. In pedigree analysis, you can look for trends such as all the sons in a family being healthy while all the daughters being affected. This could point to a sex-linked trait passed from the father since daughters get 1 X chromosome from mom and dad each. The sons on the other hand, only receive their X from the mother where the father contributes the Y chromosome in the sex pair.

What does the matrix of connective tissue layers consist of and how do they help?

The matrix consists of fibers and ground substance. Fibers help hold the tissue layers together while the ground substance helps provide for shock absorption.