Organic Molecules

What are Organic Molecules? 

Organic molecules are molecules that usually contain carbon, and are found in living organisms. They are located in the cells of living things, There are four main organic molecules that all living organisms need to survive: Lipids, Proteins, Carbohydrates, and Nucleic Acids.


Lipids are large molecules that hold a lot of energy. Lipids consist of fats, oils, and other substances. They are hydrophobic molecules, which means they do not mix well with water. Lipids hold excess energy for the body. When the body needs extra energy, it burns the fat. However, if the body is not using that supply of energy, lipids build up and can make you too fat.

There are three main categories of lipids: phospholipids, steroids, and triglyceride. Phospholipids make up most of the cell membranes around your cells. Steroids are also found in the membranes of your cells, but not as much as phospholipids.

Triglyceride is an unwanted lipid because it causes people to become too fat. When the body cannot store any more glucose it gets from food into glycogen, it creates triglyceride and stores it in them. The triglyceride is then deposited in adipose tissue, which is all around your body. This is why when you eat too much food, you get fat.


Proteins are complex and diverse molecules that carry out many functions for our body. Proteins provide structure in our cells, carry important molecules around the body, and can be used as enzymes; they speed up chemical reactions. Proteins are made up of amino acids. Amino acids are what make up most of a protein molecule. They link into chains through dehydration synthesis. The order and types of amino acids in a chain determines the type of protein that will be created from it. These chains of amino acids are called polypeptide chains.


Carbohydrates are complex molecules consisting of carbon, hydrogen, and oxygen atoms that form in the ratio of 1 carbon atom : 2 hydrogen atoms : 1 oxygen atom. Carbohydrates are taken from food. They provide energy to the body, which can be made quickly but does not last long. This is why your body needs to eat often.

Carbohydrates are classified into four broad categories: monosaccharides, disaccharides, polysaccharides, and oligosaccharides. Monosaccharides are carbohydrates with 3-7 carbon atoms in their molecules, and disaccharides are two monosaccharides linked together. Monosaccharides and disaccharides are types of sugars. Polysaccharides are long chains of monosaccharides, usually 100’s. Oligosaccharides are molecules consisting of usually 3-9 monosaccharides. Polysaccharides and oligosaccharides are not types of sugars.

Nucleic Acids

Nucleic acids include DNA and RNA, which are extremely important for all living organisms. Nucleic acids are made up of nucleotides. Nucleotides are molecules that consist of a nitrogenous base( a molecule that contains nitrogen that holds the entire molecule together), a sugar with 5 carbon atoms, and a phosphate group(a phosphorous atom linked to 4 oxygen atoms).