Unit 2 Reflection

Unit 2 Reflection

Unit 2 was about macromolecules, subatomic particles, elements, and chemical reactions. The macromolecules are lipids, carbohydrates, nucleic acids, and proteins. The subatomic particles of atoms are protons which are positively charged, electrons which are negatively charged, and neutrons which are neutral. Elements are the most basic form of something; unable to be divided further.

Macromolecules have four subcategories, lipids, carbohydrates, nucleic acids, and proteins. Where are lipids found? What are they? Lipids are found all over the body and are somewhat of a fat; they store fat for later usage. But what are these carbohydrates that everyone is trying to lose? These are fat cells, and the nemesis of all weight losers. Food contains carbohydrates, which is why weight losers try to cut weight by cutting food intake. Nucleic acids and proteins work hand in hand. When a human consumes proteins, they are broken down into nucleic acids. Nucleic acids are the building blocks of protein, so they reassemble to create a different protein that the human can use. The picture shown below is wheat and bread, which are both carbohydrates. Example of lipids would be wax and oils.

Subatomic particles fall toward the chemistry side of biology. They are protons which are positively charged, electrons which are negatively charged, and neutrons which are neutral. Why does this matter to biologists? That is because bonds do. Bonds involve electrons, which are shared between atoms in covalent bonds. In ionic bonds, this isn’t so fair. One atom will gain electrons, while the other one loses electrons. They don’t share; one gives one takes. In this sense, subatomic particles are “bonded” with biologists! What is the difference between these subatomic particles besides charge? Size. Protons and neutrons are absolute giants compared to electrons. Electrons are so small that they don’t even contribute to atomic weight. Atomic weight is used to describe elements, which are the most basic form of a molecule; they cannot be divided further. The picture shown below is a basic atom, showing the location of each subatomic particle.

Chemical reactions involve the interaction of two or more elements. This will result in a product, something different from what the substrate was. The substrate is the “input” and the product is the “output”. There are helpful molecules called enzymes that speed up the reaction. They speed up the reaction by lowering activation energy. Activation energy is the amount of energy that is required to initiate the reaction. For example, the picture shown below is a neutralization reaction. This is a reaction that cancels the pH of HCL, a strong acid, and NaOH, a strong base. Those two were the substrates, leaving salt and water as the product.