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.
There are 11 organelles in total,
vacuoles: they store water
Chloroplasts: trap energy from the sun to produce food for plant cell
Cell wall: provides support and protection to the cell membrane,
Cell membrane: thin flexible barrier around a cell, controls what enters/ leaves the cell
Nucleus: 'The control center', carries the DNA of the cell
Ribosomes: Found in all cells, their jobs are to make protein
Endoplasmic Reticulum: The internal delivery system of the cell
Golgi complex: Transports materials throughout the cell
Lysosomes: Break down food into particles the cell can use. another function is they destroy old or dying cells
Mitochondria: Breaks down food to make ATP
and last but not least cytoplasm a jelly like fluid in the cell that keeps the organelles suspended
1. Similarities:
they are both processes of cell division by which cells reproduce.
They share several steps of the process(prophase, metaphase, anaphase e telophase, cytokinesis) but meiosis has another division also with those same steps.
In both cases the cell duplicates its DNA by pulling it
apart into two sets, place the sets on each end of the cell, and then
divide down the middle.
Both produce new cells
based on their parent cells' genes.
2. The differences:
Mitosis:
- has 1 division per cycle
- one cell produces 2 new cells
- the genetic information in the mother-cell and the daughter-cells are the same. ( the number of chromosomes is also the same)
- it occurs in somatic cells
Meiosis:
- two divisions per cycle.
- one cell when divides produces 4 new cells
- the new cells have different genetic information. mixes the the genetic material from the
parent cells
- the number of chromosomes of the daughter cells is half of the mother's.
