Unit 3 Biochemistry Notes PDF

# Unit 3 Biochemistry ## Biochemistry General Notes ### A) Monomer & Polymer - Monomer: single unit, building blocks of larger molecules, linked together to create: - Polymer: large molecule, chain of monomers - Biological macromolecule. - 4 major groups: - Carbohydrates - Proteins -...

# Unit 3 Biochemistry ## Biochemistry General Notes ### A) Monomer & Polymer - Monomer: single unit, building blocks of larger molecules, linked together to create: - Polymer: large molecule, chain of monomers - Biological macromolecule. - 4 major groups: - Carbohydrates - Proteins - Lipids - Nucleic Acids ### B) Organic compound - Definition: - all contain carbon & hydrogen - Produced by living organisms naturally - Common elements: Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur (CHONPS) - Examples: Earwax, Collagen, hemoglobin, glucose, breast milk ### C) Describe & show dehydration synthesis & hydrolysis - **Dehydration synthesis:** - Removing H₂O from between 2 molecules in order to form a bond - **Hydrolysis:** - Adding H₂O would break molecules apart ## I Carbohydrates - energy & structural ### A) Name general monomers & polymers - **Monomers:** monosaccharides - Simple single-ringed sugars: - Glucose - Galactose - Fructose (C₆H₁₂O₆) - **Polymer:** polysaccharides - Complex carbohydrates/polymer - made of chains of monosaccharides ### B) Examples of monosaccharides, polysaccharides, and disaccharides - **Monosaccharides (single-ringed)** - Ex: Glucose, Galactose, Fructose (C₆H₁₂O₆) - Same formula, different composition. - **Disaccharides (two single - formed by dehydration synthesis)** - Ex: - **Maltose** = Glucose + Glucose - **Sucrose** = Glucose + Fructose - **Lactose** = Glucose + Galactose - **Polysaccharides (chains of units)** - Ex: - **Starch (plants)** - Energy storage - **Glycogen (liver)** - Energy storage - **Cellulose (plant cell walls)** - Structural - **Chitin (insect exoskeleton)** - Structural ### C) Recognize structure monosaccharides/glucose - Monosaccharides - single-ringed carbon/oxygen chain. - Glucose: - [Diagram of a glucose molecule with all components labeled] ### D) Overall function of carbohydrates in the body - Storage of energy (shorter term) - Energy production - Structure for organisms - Energy for cellular respiration ### E) Function of polysaccharides - **Starch (Plants)** - Molecule plants store excess sugar in - In roots, stem, leaves - Digestible - **Glycogen (liver)** - Stored - Molecule animals store excess sugar in - **Cellulose (plant cell walls)** - Tough, structural - Indigestible - **Chitin (insect exoskeleton)** - Tough, structural - In insects, spiders - **Starch, Cellulose** - Plants - **Glycogen, Chitin** - Animals ## II Proteins - chemical and structural ### A) Monomers & Polymers - **Monomers: Amino acids** - 20 different kinds (replacement group) - Essential & non-essential - 4 parts: - Amino group - Carboxyl group - Replacement group - Hydrogen - **Polymers: Polypeptides** - Long chain of amino acids - Sequence of amino acids matters - 50 - 100,000 amino acids ### B) # of different amino acids, essential v. nonessential - 20 different kinds (20 different kinds of "replacement groups") - Replacement group determines if the amino acid is essential or non-essential. - **Essential:** cannot be produced by the body, must be ingested. - **Nonessential:** can be produced by the body, does not need to be ingested. ### C) General Structure of a Amino Acid, "R" group - [Diagram of an amino acid with all components labeled] ### D) Peptide bond due to dehydration synthesis - [Diagram of two amino acids linked together by a peptide bond] ### E) Lock and Key Theory - How enzymes promote reactions: - Enzyme - catalyst: speeds up chemical reactions - Substrate - substances undergoing a chemical reaction - [Diagram of the lock and key model with the enzyme and the substrate] ### F) Define Enzyme & Substrate - **Enzyme** - Organic catalyst (speeds up chemical reaction) - Globular proteins - Reacts only with 3D shape matching substrate - **Substrate** - Substance(s) undergoing chemical reactions - Enzyme bonds are temporary ### G) Fibrous vs. Globular Proteins (structure) - **Fibrous:** - Long, straight chains. - **Globular:** - Chains folded into 3D shapes ## IV Lipids ### A) characteristics/functions - Long term storage of energy in animals, reserves insoluble in water. - Hydrophobic = non-polar - Triglycerides - Waxes - Steroids ### B) Monomers & polymers - Monomers: Glycerol & fatty acids - Fatty acids - Saturated v. unsaturated - Polymers: Triglycerides - Found in fats/oils ### C) characteristics of fats and oils |Type | State of Double bonds | Saturated | Unsaturated | Health | Source | |:-------|:--------------------------|:-----------|:-------------|:------------|:----------------------| | Fats | Solid | Saturated | Less | Less healthy | Animals: Bacon, Butter | | Oils | Liquid | Unsaturated | More | More healthy | Plants: Canola, olive oil | ### D) Diagram triglyceride formation - [Diagram of a triglyceride being formed from glycerol and fatty acid chains] ### E) Non-triglyceride lipids - **Waxes:** Structural - **Steroids:** Chemical - 4 rings of carbon - Elements attached to rings: - Cholesterol, testosterone ### F) Phospholipids: - Modified triglyceride - Within cell membrane - Polar & non-polar: - (-) phosphate - Hydrophilic - Fatty acid chains - Hydrophobic - [Diagram of a phospholipid molecule with the polar and non-polar regions labeled] ## V. Nucleic Acids ### A) Role of DNA & RNA in cells (structure) - **DNA** - Copied during cell division (double-strand) - Found only in nucleus - Stores genetic code - Determines protein structure - **RNA** - Temporary copy of genetic code - Directly translated into proteins - Messenger - Found in: nucleus, ribosome, cytoplasm of cell - [Diagram of a DNA molecule showing the bonds between the nucleotides] ### B) Diagram Nucleotide + DNA vs. RNA - [Diagram of a nucleotide] - **DNA** - **A, G, C, T** - **Deoxyribose** sugar - **Phosphate** group - **Double-strand** - **RNA** - **A, G, C, U** - **Ribose** sugar - **Phosphate** group - **Single-strand** - **2 copies** ## VI. Properties of Water ### A) Polar vs. Nonpolar, Hydrophobic vs. Hydrophilic substances - **Polar (hydrophilic):** - Phosphate group (-O-H) - Molecule with both (+) and (-) charged areas - **Nonpolar (hydrophobic):** - Fatty acids - Molecule that has no charge ### B) Diagram & Describe formation of Hydrogen bonds in water: - **Hydrogen bonds:** attraction between oppositely charged regions of two neighboring polar molecules. - [Diagram of two water molecules forming a hydrogen bond] ### C) Properties of Water - **Temperature Stabilization** - Resisting dramatic temperature change. - **Ice less dense than water** - High heating point. - **Capillarity:** - **Adhesion** - Attraction: water; other molecules. - **Cohesion** - Hydrogen bond between water molecules - **Solubility** - Dissolves polar/ionic substances easily - Water-loving (hydrophilic) - **Doesn't combine with non-polar substances** - Cannot touch water, doesn't dissolve easily. ## VII. Chemical Reactions ### A) Reaction Coordinate Exergonic vs. Endergonic - **Exergonic:** Energy is released - **Products** have **lower** potential energy than **reactants**. - **Endergonic:** Energy is absorbed - **Products** have **higher** potential energy than **reactants**. - [Diagram of a reaction coordinate showing the energy changes for an exergonic and an endergonic reaction] ### B) Catalyzed vs. Uncatalyzed Reaction Pathway - **Uncatalyzed:** - Reactants have a **higher** activation energy than **products**. - **Catalyzed:** - The activation energy for the reaction is **reduced**. - [Diagram of the reaction pathway for both catalyzed and uncatalyzed reactions] ### C) Activation Energy + Relationship to Catalyst - **Activation energy:** energy needed to start a chemical reaction. - **Catalyst:** speeds up reaction by reducing activation energy. ### D) Laws & Why A Chemical Equation Should Be Balanced - **Law of Conservation of Energy:** - Energy cannot be created or destroyed. - Total energy is equal before and after a reaction. - **Law of Conservation of Matter:** - Matter cannot be created or destroyed. - A balanced chemical equation must be balanced because the total amount of matter is equal before and after a reaction. ### E) Aqueous - Dissolved in Water - Reactants ~ Products ## VIII Acids & Bases ### A) Nature of Aqueous Solutions, Solutes, & Solvents - **Aqueous Solutions:** dissolved in water: - The solvent = water. - The solutes = substances dissolved in water.