BIOCHEMISTRY Biomolecules The molecules that make up and run your body

Hydrogen Bond Attractive force BETWEEN molecules NOT a true chemical bond; very weak Only form when molecules are very close together Determine the shapes of DNA and proteins

Hydrogen Bonding

4 Types of Macromolecules

ORGANIC vs. INORGANIC MOLECULES Organic Molecules contain carbon in the presence of hydrogen. Inorganic molecules are not organic; they are NOT derived from living matter.

CARBON COMPOUNDS All Macromolecules contain Carbon! Carbon is unique because it has 4 valence electrons and can bond with many other atoms. Carbon can bond with other carbon atoms and form long organic chains.

Macromolecules Constructed of units called POLYMERS Polymers are subdivided into their basic units called MONOMERS.

Macromolecules Polymers account for the molecular uniqueness of organisms. FOR EXAMPLE: ~20 amino acids make up all forms of life. These form every conceivable protein known to man!

Making & Breaking of Polymers

Making Polymers Dehydration Synthesis – two molecules are chemically joined through the use of enzymes and a loss of water

Making & Breaking of Polymers Hydrolysis – the bonds between monomers are broken by the enzyme and the addition of water.

Biomolecules overview Amoeba Sisters

Macromolecules (AKA Biomolecules) Carbohydrates

Carbohydrates Made of C, H, and O Monomer = Monosaccharide Function: To supply IMMEDIATE energy for all cell activities

Monosaccharide Single Sugar

Monosaccharide Examples Pentose sugars = 5 carbons Ribose, deoxyribose, and ribulose Hexose sugars = 6 carbons Glucose, galactose, fructose

Glucose: Your brain’s favorite food

Disaccharides Examples: Sucrose Maltose Lactose NOTICE: Mono & Disaccharides end in the suffix -ose

Structural or storage molecules Polysaccharides Many sugars Basic Formula: ( C6H10O5)n Structural or storage molecules

Carbohydrate Review Type Function Examples Monosaccharide Immediate energy Glucose, Fructose Disaccharide Sucrose, Maltose Polysaccharide Structure and Storage Starch, Glycogen

Storage Polysaccharides “Complex carbohydrates” (ENERGY STORAGE) STARCH is a PLANT storage polysaccharide that is composed entirely of glucose molecules Amylose is the simplest form of starch

Storage Polysaccharides Glycogen - animal starch stored in the liver and skeletal muscles of vertebrates PLANTS make their own carbohydrates ANIMALS eat the plants FOOD/ENERGY WEB IN ACTION!!

Glycogen Storage

Using Glycogen If your blood sugar (glucose) gets too high: Your body stores it in your liver and skeletal muscles as glycogen If your blood sugar gets too low: Your body breaks down the glycogen and releases glucose to your blood

Structural Polysaccharides Cellulose and chitin Cellulose is the most abundant organic compound on earth. Chitin is found in arthropod exoskeletons and the cell walls of fungi

Structural Polysaccharides Cellulose in cell walls of plants must be broken down into glucose before cells can use it for energy cows, termites, and roaches have microbes in their digestive tracts that do this for them WE DON’T – that is why we can’t graze on grass for lunch!! However, we do need cellulose although we just call it FIBER in our diet: It scrubs out our intestines!

In charge of all your body functions PROTEINS In charge of all your body functions

Proteins Biomolecules that are provide structure or have a function Monomer: Amino Acid Elements: C, H, O, and N

Basic amino acid structure

20 main amino acids

Protein formation Dehydration synthesis joins the amino acid monomers together using peptide bonds Sometimes called “polypeptide chains” Make up ~50% of dry weight of most cells

Functions of Proteins Wide variety of functions...can be divided into 2 categories: STRUCTURAL: support and strengthen FUNCTIONAL: crucial roles in biological processes Proteins are VERY IMPORTANT!!!

Structural Proteins

Functional Proteins

Cell Membrane Proteins

Protein Hormones

Proteins Structural Proteins Support and strengthen Elastin Artery walls, lungs, intestines, skin Collagen Skin Keratin Hair, nails, skin Functional Proteins Crucial role in biological processes Hemoglobin In blood cells - carries oxygen to cells Insulin Pancreas - carries glucose to cells Antibodies & Antigens White blood cells - fight infection Enzymes Saliva, stomach - speed up reactions

Enzyme action Enzymes can act as “catalysts” (a molecule that lowers ACTIVATION ENERGY) Can increase a reaction’s speed (rate) up to 1010 times!! The enzyme is not changed at all by the chemical reaction so can be reused over and over

Enzyme Specificity Enzyme: protein that acts on a substrate Substrate: molecule that is affected by the enzyme Active site: place on the enzyme where the reaction occurs ONE ENZYME ACTS ON ONLY ONE SUBSTRATE: VERY SPECIFIC ! Amylase breaks down amylose Lactase breaks down lactose

Enzyme Action Lock and key fit: active site and substrate fit exactly Induced fit: active site can adjust to “wrap around” substrate to get optimum fit

Protein Denaturation Functional Proteins depend on their structure to do their job STRUCTURE DETERMINES FUNCTION Active site must be the correct shape for the substrate H-bonds hold these proteins together in their correct shape

Protein Denaturation Extremes (too high or too low) in TEMPERATURE and pH can disrupt H-bonds causing the active site to be destroyed. The enzyme CANNOT do its function! The enzyme (protein) is then denatured (Not the same nature as before)

Enzyme-Substrate Action

LIPIDS

Lipids Biomolecule that contains C, H, and O HYDROPHOBIC (non polar): doesn’t mix with water Monomers: Glycerol and 3 fatty acids Examples: neutral fats, steroids, and phospholipids

Neutral Fats Monomer

Dehydration Synthesis

Neutral Fats Monomers: Glycerol and 3 fatty acids Functions: INSULATION (subcutaneous fat) Energy storage (Very energy dense: Fat has 9 kcal of energy per gram, while Carbs & proteins have 4 kcal of energy) Cushioning for internal organs Absorption of fat soluble vitamins (A, D, E, K; these vitamins cannot be absorbed unless they are dissolved in fat)

Saturated Fats vs. Unsaturated BAD GOOD Characteristic Saturated Fats Unsaturated Fats State at room temp. Solid Liquid Found in animals or plants Animal Plants Structure: bent or straight Single bonds, straight Double bonds, bent

Saturated Unsaturated

Steroids Monomers are carbon skeleton of 4 fused rings (add to your notes!)

Steroids Steroids are FAT SOLUBLE and contain little oxygen THE FOLLOWING ARE EXAMPLES: Cholesterol is found in all ANIMAL tissue. Plants do NOT contain cholesterol Cholesterol is the MOST IMPORTANT steroid since it is essential for the manufacture of ALL other steroids It also helps to STABILIZE your cell membranes.

Examples Sex hormones: estrogen, testosterone, progesterone Insulin: blood glucose regulation (add to notes) Aldosterone: maintains water balance Bile salts: digestion & absorption of FATS

Phospholipids Monomers: two fatty acids and a phosphate Functions: Form cell membrane: Phospholipid bilayer Component of Nervous Tissue

Phospholipids Both polar and non polar qualities Phosphate head is polar Fatty acid tail is non polar

Phospholipid Bilayer

Myelin Sheath: Insulates Nerve

NUCLEIC ACIDS GENETIC MATERIAL

Nucleic Acids Biomolecules that store and transmit genetic information Contain elements C, H, O, N, P Monomer: Nucleic acid Phosphate Nitrogenous base Sugar (ribose or deoxyribose)

DNA & RNA

Nucleotides

DNA INFORMATION Cellular site = nucleus Function = Directs protein synthesis (contains all the instructions) Sugar = deoxyribose Nitrogenous bases = A T C G Structure = double helix

RNA INFORMATION Cellular site = in & out of nucleus (can travel) Function = Carries out protein synthesis (makes it happen) Sugar = ribose Nitrogenous bases = A U C G Structure = single strand

Elements in Macromolecules Carbohydrate C,H,O Lipids C,H,O,(P) Proteins C,H,O,N Nucleic Acids C,H,O,N,P

Monomers Carbohydrates Mono- saccharides Lipids (neutral fats) Glycerol & fatty acids Proteins Amino Acids Nucleic Acids Nucleotides

Major function Carbohydrates Immediate energy & storage Lipids Cell components Form steroids Proteins Functional Structural Nucleic Acids Store and transmit genetic info