Proteins. Biomolecules. Nucleic Acids. The Building Blocks of Life

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1 Proteins Biomolecules Nucleic Acids The Building Blocks of Life Carbohydrates Lipids

2 Biomolecules are Organic Molecules 1. Organic molecules that are Carbon based (at least 1 Carbon molecule and often chains of Carbon) They all contain Carbon and Hydrogen and often Nitrogen and often Oxygen. Examples of organic molecules: Methane (CH 4 ) Glucose (C 6 H 12 O 6 ). What about CO 2? 2. They make up living organisms

3 Chemistry of Living Things Organic Compounds: Molecules that are found in living things. Organic compounds contain carbon. Why Carbon? With an atomic number of 6, carbon has 4 valence (outer) electrons, in the 2 nd energy level which holds 8 electrons. Because it needs to share 4 electrons to be stable, it can form 4 bonds with a wide variety of elements and form complex molecules.

4 Biomolecules 1. Basic Molecules: Proteins, Carbohydrates (sugars), Lipids (Fats), Nucleic Acid (DNA, RNA) 2. Macromolecule: Large molecules consisting of bonded smaller molecules. They are also called polymers (poly = many) Ex: Starch is a macromolecule Made of many glucoses bonded Together.

5 Biomolecules 1. Subunits: The smaller molecules that are the building blocks of macromolecules Sugars that make up starch or cellulose Amino Acids that make up Proteins Fatty acids and glycerol make up lipids

6 Carbohydrate Simple vs. Complex sugars DRAW THIS MOLECULE Of GLUCOSE Simple sugars: Monosaccharide: One Sugar We will focus on glucose: C 6 H The basic source of energy for cells.

7 Simple Sugars:Carbohydrates Simple Sugars: Disaccharide Two Sugars Examples: -Sucrose (table sugar)= Glucose + Fructose Maltose= Glucose + Glucose

8 Complex Sugars: Polysaccharide many sugars = Complex Sugar. Examples: Starch : has thousands of glucoses (sugars) bonded together Thousands

9 Complex Sugars: Polysaccharides Cellulose: Makes up the walls of plant cells. Also made from glucose. Ruminants (cattle, sheep) can digest both cellulose and glucose. Humans can digest starch, but not cellulose WHY??????????

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11 Polysaccharides Glycogen: Animals store carbohydrates (glucose) in the form of glycogen; similar in form to starch. Why???? This is why This is our short term reserve energy Stored in liver and muscles We do not want to lose our carbs all at once!!

12 Functions of simple and complex carbohydrates Functions: Cells use carbohydrates as their main source of energy. Simple sugars can quickly be used by cells to get the energy they need. Complex carbs need to be broken down to be absorbed and used. The slow breakdown allow organisms to gradually use energy since it is stored in a large structure. (like the Bank) Plants use cellulose for their cell wall which provides structure and support.

13 Proteins Made of Amino Acid Chains Amino Acids are bonded through a peptide bond

14 Each ball is An Amino Acid. Bonded by Peptide Bonds There are 20 Amino Acids

15 There are 20 different occurring amino acids

16 Protein Function 1. Building material: connective tissue (collagen), muscle, hair, fingernails (keratin) 2. Enzymes: Help with chemical reaction in the cells and body (catalyst) 3. Immunity: make up antibodies 4. Other specific functions such as Hemoglobin: carry O 2 in red blood cells Communication between cells: Receptors, transport channels, cell recognition

17 Examples of Protein Structures The shape of protein is important to its function. Enzyme: Quaternary Structure

18 Enzymes are involved in nearly all metabolic processes: Example: Digesting (breaking down) food Releasing energy Synthesis (building) of molecules Pepsin is an enzyme in the stomach that digests proteins into amino acids.

19 The 3-dimensional shape of a protein is important for its function. Under certain conditions, a protein may become unfolded and will not be able to perform its function. This unfolding of a protein is called denaturation.

20 Lipids (Fats) A common lipid is made of 3 fatty acids chains connected to a glycerol

21 Lipids (Fats) Glycerol: a type of alcohol. The back bone of Fats. 3 Fatty acid chains: Long chains of C & H Saturated=as many Hydrogens bonded as possible (Solid at Room Temp.) Unsaturated= C and C bonds can be double which decreases the amount of Hydrogens bonded and kinks the chain (usually Liquid at Room Temp.)

22 Saturated vs. Unsaturated

23 Lipids (Fats) Functions The main energy storing molecule in the body because of the high percentage of carbon to carbon bonds which store more energy than other bonds. Why are bonds important? because they Store chemical energy Lipids store more energy than any other biomolecule 9 Cal/gram = lipids 4 Cal/gram = carbohydrates and proteins

24 Lipids (Fats) Functions Insulate and protect Main molecule of the Cell membrane Make up some hormones (testosterone) Storage molecule for energy

25 ?Questions? What type of bond connects Amino Acids? What are common lipids composed of? What are three types of carbohydrates? What is the subunit for polysaccharides? What are the four types of elements that make up biomolecules?

26 Nucleic Acids Composed of subunits called nucleotides. There are 2 Types of Nucleic Acids: DNA and RNA Stores hereditary information in the cell by the order of the bases A, C, T and G

27 Synthesis of Polymers: Condensation Reactions Many polymers are built by reactions called condensation reactions. An OH group from one subunit is linked with a H on the other subunit, forming water. The subunits are linked covalently together.

28 When 2 amino acids are linked together by a condensation reaction, the bond is called a peptide bond.

29 Breaking down Polymers: Hydrolysis Reactions When sugars, proteins or lipids are broken down into their subunits, the opposite process occurs. Water is used in this process to break apart the polymer, so it is called a hydrolysis reaction (hydro= water, lysis= to break)

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31 Animation of condensation and hydrolysis reactions rmation.html oac/biochem/condense.htm

32 Energy Storage in Biomolecules Energy is stored in the bonds of biomolecules Some bonds can store more energy than others. For Biomolecules, carbon bonded to carbon can store more energy than others. The higher the percentage of carbon to carbon bonds, the more energy that can be stored for the same amount.

33 Energy Storage Energy in biomolecules can be measured using units of food calories. Carbohydrates Proteins Lipids

34 Energy Storage For the same amount of each type of biomolecule below, which one has the most energy? Why? Carbohydrates Proteins Lipids

35 Biomolecules and Energy Fats have 9 Calories per gram Proteins and Carbohydrates both have about 4 Calories per gram Fats can store more energy because of the large percentage of carbon to carbon bonds.

36 Application Question Our bodies and many other organisms store their long term excess energy as fat. What is the advantage of storing this energy as fat instead of complex carbohydrates?

37 Practice Questions Match the biomolecule (carbohydrates, lipids, proteins, nucleic acids) with its function: 1. Help speed up reaction in cells by acting as enzymes 2. Provide insulation to our bodies 3. It is the main energy source for our cells 4. Stores genetic material to be passed onto new cells 5. It is used to make up cell walls in plants 6. It can store the most energy and is used for long term energy storage in animals 7. Act as building and support molecules such as connective tissue and hair.

38 Help speed up reaction in cells by acting as enzymes Proteins act as enzymes 2. Provide insulation to our bodies Lipids 3. It is the main energy source for our cells Carbohydrates 4. Stores genetic material to be passed onto new cells Nucleic Acids make up DNA 5. It is used to make up cell walls in plants Cellulose is a type of Carbohydrate 6. It can store the most energy and is used for long term energy storage in animals Lipids 7. Act as building and support molecules such as connective tissue and hair. Protein