Life Substances

1. Science is cool! Life Substances Biology Section 6.3

2. Challenge:How many words can you make from the below letters? T E A T R S Turn to your partner and discuss: Use this example to explain how only 90 natural elements could form all the different substances on Earth

3. To Summarize: We are made of specific elements. Much of our biochemistry is derived from carbon, hydrogen, oxygen, & nitrogen. These 4 elements can be combined and rearranged in different ways to form different biomolecules. A biomolecule is a large organic molecule found in all living organisms. - All organic molecules contain carbon

4. Triple Bond Double Bond Single Bond Because: A carbon atom has four electrons available for bonding in its outer energy level. In order to become stable, a carbon atom forms four covalent bonds that fill its outer energy level. Carbon WHY? Carbon is able to bond in many ways, therefore making it possible to have a huge number of carbon structures.

5. Our cells build biomolecules by bonding together chains of smaller molecules. These chains are called POLYMERS. A polymer is a large molecule formed by many smaller molecules bonded together. Think: what do you think you call a “single” subunit of a polymer? - Answer: Monomer

6. You are what you eat! • We are made of 4 types of organic molecules: Example: When you eat meat, the proteins in them are chopped up and rearranged into your own proteins – we recycle! Carbo's, proteins, lipids, and nucleic acids!

7. 4 Types of Biomolecules #1 A carbohydrate is a biomolecule that is made of repeating carbon, hydrogen, and oxygen molecules. They can be small (a single monomer or short chain) or large (long chains)

8. The structure of carbohydrates • The simplest type of carbohydrate is a simple sugar called amonosaccharide. (Give me an example of a common simple sugar!?) Glucose and Fructose! • A sugar made of 2 monosaccharides is called a ___________. Sucrose & Lactose disaccharide • The largest carbohydrate molecules are polysaccharides, polymers made of many monosaccharide subunits. (ie. potatoes, liver) Fuel! Why are carbo's important to us?

9. #2 - Lipids • Lipidsare large biomolecules that are made mostly of carbon and hydrogen with a small amount of oxygen. (ie. fats, oils, waxes) Question: Have you ever had oil or butter on your hands and find that you cannot wash it off with water alone??? • Lipids are insoluble in water because their molecules are nonpolar (not attracted by water molecules)

10. An example of a Lipid is a Fatty Acid Fatty acids are the building blocks to lipids. They are looooooonnnng chains of carbon and hydrogen Fatty acids are found in many dairy and meat products as well as oils.

11. Fat-Schmat! Lipids are important! Our cells use lipids for • Energy storage • Insulation • Protective coverings Fact: Lipids are the major components of membranes that surround all living cells!

12. Lipids Fill in the blank: Saturated fats contain ________ bonds, while unsaturated fats have a ________ bond. Remember: Saturated fats are “saturated” with hydrogen atoms, while unsaturated fats have a double bond between carbon atoms thus are not completely saturated with hydrogen atoms. single double

13. #3: Proteins Proteins are large polymers made of carbons, hydrogens, oxygens, nitrogens, and sometimes sulfur. The basic building blocks of proteins are Fact: There are about 20 common Amino Acids that in different combinations can form thousands of proteins! Amino Acids!

14. Proteins, con’d Proteins are made of amino acids, and all amino acids are composed of an amine group (NH2) at one end and a carboxyl group (COOH) at the other. In between them is the “side chain” (aka R group). The R-group is what differs between each amino acid.

15. Why are proteins important? • Provide structures for tissues (hair fingernails, horns, and hoofs) • Carries out metabolism • Help to contract muscle tissue • Transporting oxygen in our bloodstream • Providing immunity • Regulating other proteins • Carrying out chemical reactions

16. One type of protein is anENZYME Enzymes are important proteins found in all living things. They change the rate of chemical reactions. Example: Some enzymes help to speed up the digestion of our food.

17. Digestion Example So how do enzymes work? They work like a lock and key Important terms: The molecules involved are called the ‘substrates’. The new substances formed by the chemical reaction are called the ‘products’

18. Need another example? Summary & Animation: http://www.bbc.co.uk/education/asguru/biology/02biologicalmolecules/01proteins/11enzymes/index.shtml

19. #4 Nucleic Acid Nucleic Acid is an important biomolecule that stores cellular information in the form of a code. Nucleic acid is a polymer made up of smaller subunits called Question: What is a popular nucleic acid that you have heard of? Nucleotides Answer: DNA!

20. The structure of nucleic acids • Nucleotides are arranged in three groups—a nitrogenous base, a simple sugar, and a phosphate group. Phosphate Sugar Nitrogenous base

21. Why is Nucleic Acid Important? Nucleic acid, like DNA, is important because it forms the genetic code that determines how an organism looks and acts Another nucleic acid, RNA, is important because it helps in making proteins that are essential to our survival

22. Assignment Now use your notes to fill in your biomolecule foldable I will be checking your foldables at the beginning of our next class