Macromolecules copyright cmassengale
Organic Compounds Compounds that contain CARBON are called organic. Macromolecules are large organic molecules.
Carbon (C) Carbon has 4 electrons in outer shell. Carbon can form covalent bonds with as many as 4 other atoms (elements). Usually with C, H, O or N.
Macromolecules Large organic molecules. called POLYMERS. Made up of smaller repeating “building blocks” called MONOMERS. Examples: 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids (DNA and RNA)
Question: How Are Macromolecules Made?
Answer: Dehydration Synthesis Also called “condensation reaction” Forms polymers by combining monomers by “removing water”. Answer: Dehydration Synthesis HO H H2O HO H
Question: How are Macromolecules broken down?
Separates monomers by “adding water” Answer: Hydrolysis HO H H2O HO H
Carbohydrates
Characteristics of Carbohydrates Consist of carbon, hydrogen, and oxygen The monomer of a carbohydrate is a monosaccharide Monosaccharides are simple sugars Glucose and fructose are two examples of monosaccharide isomers Characteristics of Carbohydrates
Representing Molecules When these simple sugar monomers are represented, the atoms in the ring are not usually shown Same as
Forming Carbohydrates In forming carbohydrates, sugar (monosaccharide) monomers link together They can link in straight chains or branching As straight chains, it would look like this sugar - sugar - sugar - sugar - sugar sugar sugar sugar sugar sugar sugar sugar sugar
How many link together? The number of sugar monomers linked will vary with the type of carbohydrate For example: If two monosaccharide monomers are linked it forms a disaccharide such as sucrose Prefix mono- means one and prefix di- means two
Polysaccharide Prefix poly- means many, so a polysaccharide consists of many linked monosaccharide monomers Polysaccharides can be in linear chains or branched
How do they link? When two monomers link, the –OH groups on the two monomers react and release water as shown
What happens to carbohydrates in the cells? Carbohydrates are broken down by cells back into the sugar monomers for energy Water must be added back to the carbohydrate in order for this to happen This is one of the reasons why living things need water!
Function of Carbohydrates Carbohydrates have two main functions 1) Energy 2) Structure
Energy Plants store energy as the carbohydrate starch Animals store energy in their liver and muscles as the carbohydrate glycogen
Structure In plants, the cell wall is made of the carbohydrate cellulose In some animals, the carbohydrate chitin forms the exoskeleton
Digesting Carbohydrates In order to use carbohydrates for energy, animals must break apart the carbohydrate polymers – called digestion Starch is easy to digest – most animals are able to Cellulose is difficult to digest – only some animals are able to
Different Diets of Herbivores Cow can digest cellulose well; no need to eat other sugars Gorilla can’t digest cellulose well; must add another sugar source, like starches and fruit to diet