Unit 2 Lecture Study Guide

Unit 2 Lecture Study Guide

1. The 2 parts of an atom are the central nucleus and the electron cloud. The subatomic particles are found in the nucleus.

2. The atomic mass number is determined by adding together the number of protons and neutrons in the nucleus. The atomic number is the number of protons in the nucleus.

3. An isotope is atoms of the same element that have different mass numbers due to different numbers of neutrons. An example of an isotope would be a radioisotope, which emit radiation in the form of subatomic particles. The amount of radiation decreases over time, or decays, at a rate that is specific to that isotope, called the half-life.

4. Ionic- Form between atoms with opposite electrical charges (Electrolytes)

Covalent- When atoms share electrons, forming molecules (Carbon dioxide)

Hydrogen- Weak attractions between the positive, hydrogen side of one polar molecule and the negative side of another polar molecule. Hydrogen bonds influence the shape of larger molecules, which is important to molecules such as proteins and DNA (DNA)

5. Because the body must function at a correct pH. If the pH is off, certain physiological reactions won't occur.

6. Carbohydrates- Organic molecules with a carbon/hydrogen/oxygen ratio of about 1:2:1, including sugars and starches. (Glycogen)

7. Lipids- Mainly hydrophobic molecules (such as fats, oils, and waxes) made mostly of carbon and hydrogen atoms. (Cholesterol)

8. Proteins- The most abundant and most important class of molecules in the human body. All body functions require proteins. (Protein = amino acid)

9. Nucleic acids- large organic molecules (made of carbon, hydrogen, oxygen, nitrogen, phosphorus) which store and process information at the molecular level. (DNA, RNA)

10. The 4 levels of protein structure are primary structure, which is the order of amino acids, secondary structure, where hydrogen bonds form, tertiary structure, which folds the secondary structure, and quaternary...