Macromolecules - types and structures

Created April 2020, Offline version here
Video by Paul Anderson, also on his website Bozeman Science.

    So, DNA is found in the nucleus of cells and is a biological that we are quite familiar with. DNA contains the instructions for all life on Earth. DNA occurs in the shape of a double . We can extract DNA from cells using soap and cold alcohol, which causes it to come out of solution. You can see strands of DNA wrapped on a nichrome wire. They are tiny, but visible with the naked eye. Strands of DNA are made up of smaller units called . Each nucleotide consists of three components. It has a 5-carbon sugar, a , and a base. RNA is also a . Its job is to carry the instructions from DNA for assembling proteins (protein synthesis). DNA and RNA are both responsible for , the passing of instructions from generation to generation. A string of DNA or always includes four bases. They are the building blocks for nucleic acids. The first three bases are cytosine, guanine, and . The fourth base is unique. For DNA it is , but not for RNA. For RNA it is . So, they are similar in structure, but RNA is a single strand. While DNA always remains in the nucleus, RNA leaves the nucleus to do its job. Remember that RNA carries instructions for protein synthesis. Proteins are made up of building blocks of , of which there are twenty different kinds.
    They are differentiated by what’s called an on the end of the molecules. Those groups give each amino acid characteristics that determine how they make a protein.
    The building blocks of proteins are assembled through dehydration synthesis, a process that removes . The building blocks of nucleic acids and carbohydrates are also assembled that way.
    Another type of macromolecule is a . It is different because it does not a repetitive chain of building blocks. Lipids are fundamental components of cell , the sac-like structures that enclose cells. There are openings in cell membranes that are regulated by proteins. The phospholipids in a cell membrane are non-polar on one end and on the other. The nonpolar part faces into the cell when they line up in a membrane. Other lipids are non-polar on both ends. When you combine them with , they do not mix, but instead separate. Fats generally have tails, which contain a lot of energy. They consist of a line of carbon atoms with hydrogen around the outside. Some lipids are , meaning they have fatty acids in a straight line. Otherwise, they would bend because of double bonds. The fourth type of macromolecule is a . From a health point of view, it is believed that are better for us in terms of heart disease risk. So, we have covered three biological macromolecules: proteins, nucleic acids, and lipids. They are made up of sugars, such as . What’s cool about carbohydrates is that they not only give use energy, but also provide structure. The that gives strength to insect exoskeletons is a carbohydrate. The in plant cell walls is also a carbohydrate.