← Chapters 2&3 Key Words Export Options Alphabetize Word-Def Delimiter Tab Comma Custom Def-Word Delimiter New Line Semicolon Custom Data Copy and paste the text below. It is read-only. Select All Element A substance that cannot be chemically interconverted or broken down into simpler substances. For example, Oxygen, Hydrogen, etc. Atom The smallest component of an element having the chemical properties of the element. Molecule The simplest structural unit of an element or compound. 6 Main Elements of Life Carbon, Oxygen, Hydrogen, Sulfur, Phosphorus, and Nitrogen. Isotopes and Radioisotopes Atoms of the same element that have different numbers of neutrons. Radioisotopes are the isotopes that are unstable, or radioactive. Valance Electrons The electrons in the outermost energy level that are available to be lost, gained, or shared when elements form chemical bonds. Chemical bonds An attraction between two atoms resulting from the sharing of outer-shell electrons or the presence of opposite charges. Ionic Bond A chemical bond in which one atom loses one or more electrons to form a positive ion and the other atom gains one or more electrons to form a negative ion. Covalent Bond A chemical bond that involves sharing one or more pairs of electrons between two atoms. Polar Covalent Bonds A type of covalent bond between atoms that differ in electronegativity. The shared electrons are pulled closer to the more electronegative atom. Making one slightly negative and the other slightly positive Hydrogen Bond A type of weak chemical bond formed when the slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule. Peptide Bond The primary linkage of all protein structures. EX. the chemical bond between the carboxyl groups and amino groups that unites a peptide. Chemical Reactions The process in which chemical bonds are broken and/or formed in order to form new substances. Functional Group Transfer One molecule gives up a functional group entirely, and a different molecule immediately accepts it. Electron Transfer The donation of valence electrons from one atom to anther to form a cation and an anion. Rearrangement One type of organic compound is converted to another type through the rearrangement of internal bonds. Condensation Reaction A reaction in which two molecules become covalently bonded to each other through the loss of a small molecule, usually water; also called dehydration reaction. Cleavage The breaking of a chemical bond in a molecule resulting in smaller molecules. ex. Hydrolysis Law of Conservation of Matter In any physical or chemical change, matter is neither created nor destroyed but merely changed from one form to another. Activation Energy The energy that an atomic system must acquire before a process (such as an emission or reaction) can occur. Ion An atom or group of atoms that has a positive or negative charge. Non-polar molecule Molecule that shares electrons equally and does not have oppositely charged ends. This type of molecules are hydrophobic, meaning they do not like water. Polar molecule Molecule that shares electrons unequally, creating a slight positive and negative charges at the end of the molecule. This type of molecules are hydrophilic, meaning water-loving. Molecular formula A chemical formula that shows the number and kinds of atoms in a molecule, but not the arrangement of atoms. Structural formula An expanded molecular formula showing the arrangement of atoms within the molecule. Water Formula: H2O Properties: -Heat regulating properties -Ice less dense than liquid water -Helps separate large chains of molecules into smaller molecules -Cohesion, the fact water can stretch through tube like structure -Transparency, allowing for sunlight to reach underwater organism Hydrogen ion Formula: H+ Charge: Positive Hydroxide ion Formula: OH- Charge: Negative Hydronium ion Formula: H₃O⁺ Charge: Positive pH scale Measurement system used to indicate the concentration of hydrogen ions (H+) in solution; ranges from 0 to 14. Acidic A pH below 7 is acidic; contains more H+ ions than hydroxide ions (OH-). Sour taste, can conduct electricity, are corrosive, and some of these react strongly with certain metals, are all properties of an acidic solution. Basic/Alkaline A substance that contains more hydroxide ions than hydrogen ions. Has a pH level greater than 7. Organic compounds Complex molecules organized around skeletons of carbon atoms arranged in rings or chains; includes biomolecules molecules synthesized by living organisms. Inorganic compounds These compounds do not contain carbon. Carbon properties Properties of carbon make it a key element in compounds found in bio systems. Carbons can form up to four bonds with different or the same atoms. Carbons can bond to each other to form large complex structures. Macromolecules Large molecules that are formed by joining smaller organic molecules together. Four main classes are: Carbohydrates, lipids, proteins, and nucleotides. Carbon Skeleton The chain of carbon atoms that form the structural backbone of an organic molecule. Monomer A simple compound whose molecules can join together to form polymers. Polymer A naturally occurring or synthetic compound consisting of large molecules made up of a linked series of repeated simple monomers. Carbohydrates Organic compounds made of carbon, hydrogen, and oxygen atoms in the proportion of 1:2:1. They are the major source of energy in our bodies. Monosaccharide A sugar (like sucrose or fructose) that does not hydrolyse to give other sugars. *chain and ring formulas for glucose and sucrose found on physical flashcards* Oligosaccharide A saccharide polymer containing a small number (typically three to ten) of component sugars, also known as simple sugars. Disaccharide A double sugar, consisting of two monosaccharides joined by dehydration synthesis. *chain and ring formulas for lactose and sucrose found on physical flashcards* Polysaccharide One of the carbohydrates made up of long chains of simple sugars; polysaccharides include starch, cellulose, and glycogen Starch Polysaccharide made up of a chain of glucose molecules; food storage molecule for plants *diagram on physical flashcards* Glycogen An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch. Cellulose Polysaccharide consisting of glucose monomers that reinforces plant-cell walls. Chitin Complex carbohydrate that makes up the cell walls of fungi; also found in the external skeletons of arthropods. Lipids Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen. Not soluble in water. Fatty acid A long carbon chain carboxylic acid. Vary in length and in the number and location of double bonds; three fatty acids linked to a glycerol molecule form fat. Glycerol Three-carbon compound with three hydroxyl groups; component of fats and oils. Glycerides Formed by the attachment to glycerol; dehydration synthesis produces monoglyceride(glycerol plus one fatty acid) diglyceride (glycerol + two fatty acids), triglyceride (gylcerol + three fatty acids) Found in animal fats and vegetable oils. *diagram with labels found on physical cards* Phospholipids Have two fatty acids attached to a molecule of glycerol. They form most of the cell membrane. *diagram with labels found on physical cards* Waxes Type of structural lipid; long fatty acids chain bonded to long alcohol chain; highly waterproof; in plants and animals. eg. Cetyl palmitate *diagram found on physical cards* Sterols Lipids that are composed of three six carbon rings and one five carbon ring fused together forming the basic structure for cholesterol, bile salts and many hormones such as cortisols, estrogens, androgens, and progesterone. *diagram found on physical cards* Saturated fat A lipid made from fatty acids that have no double bonds between carbon atoms. All three fatty acid chains contain the maximum possible amount of hydrogen atoms. Unsaturated fat A lipid made from fatty acids that have at least one double bond between carbon atoms. Proteins Contains carbon, hydrogen, oxygen, and nitrogen. Source of energy. Needed by tissue for repair and growth. Made up of 20 amino acids. *diagram and genetic formula on physical flashcard* Fibrous proteins (Structural proteins) Insoluble in water; chief building materials of the body; usually used to construct connective tissues, tendons, bone matrix and muscle fiber. Globular proteins (Functional proteins) Water soluble; chemically active molecules; spherical shape; play crucial roles in virtually all biological processes. Amino acids Compounds with an amino group (-NH₂) on one end and a carboxyl group (-COOH) on the other end; the monomers that make up a protein. Amino group A functional group that consists of a nitrogen atom bonded to two hydrogen atoms; can act as a base in solution, accepting a hydrogen ion and acquiring a charge of +1. Carboxyl (Acid) group -COOH group at the end of a hydrocarbon, forms a carboxylic acid. Functional group (R) A specific configuration of atoms commonly attached to the carbon skeletons of organic molecules and usually involved in chemical reactions. Hydroxyl group A functional group consisting of a hydrogen atom joined to an oxygen atom by a polar covalent bond. Molecules possessing this group are soluble in water and are called alcohols. Methyl group A chemical group consisting of a carbon bonded to three hydrogen atoms. The methyl group may be attached to a carbon or to a different atom. Carbonyl group A functional group present in aldehydes and ketones and consisting of a carbon atom double-bonded to an oxygen atom. Phosphate group A chemical group consisting of a phosphorus atom bonded to four oxygen atoms; important in energy transfer. Sulfhydril group (Thiols) R-SH Forms disulfide bridges in polypeptides. Stabilizes 3D structure of the protein. Polypeptide A polymer (chain) of many amino acids linked together by peptide bonds. Primary structure The first level of protein structure; the specific sequence of amino acids making up a polypeptide chain. Secondary structure The second level of protein structure; the regular local patterns of coils or folds of a polypeptide chain. Tertiary structure The third level of protein structure; the overall, three-dimensional shape of a polypeptide due to interactions of the R groups of the amino acids making up the chain. Quarternary structure Fourth level of structure; joining of the polypeptide subunits. Enzymes Molecules, usually proteins or nucleic acids, that act as catalysts in biochemical reactions. Meaning they speed up chemical reactions. Nucleic acids Very long organic compounds made up of carbon, hydrogen, nitrogen, and phosphurous, contain instructions that cells need to carry out all the functions of life. Nucleotides Monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base. Cytosine Base: One of the four aromatic bases found in DNA and RNA. Cytosine is a pyrimidine; it pairs with guanine. Adenine One of the four aromatic bases found in DNA and RNA; also a component of ATP, NADH, and FADH2. Adenine is apurine; it pairs with thymine (in DNA) and with uracil (in RNA). Thymine One of the four aromatic bases found in DNA. Thymine is a pyrimidine; it pairs with adenine. Guanine One of the four aromatic bases found in DNA and RNA. Guanine is a purine; it pairs with cytosine. Ribose A five-carbon monosaccharide found in RNA. Deoxyribose A five-carbon sugar that is a component of DNA molecules. Phosphate PO₄³⁻, makes up the sides of the DNA ladder with deoxyribose. Uracil The RNA version of thymine. Like thymine, this base also pairs with adenine. DNA A long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix. RNA A long linear polymer of nucleotides found in the nucleus but mainly in the cytoplasm of a cell where it is associated with microsomes. Adenosine phosphates (AMP, ADP, ATP, cAMP); energy carriers (e.g. ATP) and chemical messengers (cAMP). Nucleotide coenzymes Transport hydrogen atoms and electrons (NAD+ and FAD).