Notes on Vocab

Adenosine triphosphate (ATP): A molecule that carries energy within cells. It is the main energy currency of the cell.

Steroid: A type of lipid characterized by a carbon skeleton with four fused rings. Steroids include hormones like testosterone and cholesterol.

Hydrolysis: A chemical reaction that breaks bonds between two molecules by adding water; commonly used in the breakdown of polymers into monomers.

Cholesterol: A type of lipid molecule that is an essential structural component of animal cell membranes and a precursor for the synthesis of steroid hormones.

Essential elements: Chemical elements that are required for an organism to survive, grow, and reproduce.

Dehydration synthesis: A chemical reaction in which two molecules are covalently bonded to each other with the removal of a water molecule; used in the synthesis of polymers from monomers.

Catalyst: A substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.

Trace elements: Elements required by an organism in only minute quantities.

Hydrogen bond: A weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in the other.

Enzymes: Proteins that act as biological catalysts, speeding up chemical reactions in cells.

Polypeptide: A polymer of amino acids linked together by peptide bonds.

Reactant: A substance that takes part in and undergoes change during a chemical reaction.

Carbohydrates: Organic compounds consisting of carbon, hydrogen, and oxygen, typically in a ratio of 1:2:1; they serve as a major source of energy for living organisms.

Peptide bond: A covalent bond formed between two amino acids during protein synthesis.

Product: The substances that are formed during a chemical reaction.

Monomer: A small molecule that can combine with others to form a polymer.

Protein: A polymer made of amino acids that performs a wide range of functions in living organisms.

Chemical equilibrium: The state in which the rate of the forward reaction equals the rate of the reverse reaction, so that the concentrations of reactants and products remain constant over time.

Polymer: A large molecule composed of repeating structural units (monomers).

Amino acid: Organic molecules that are the building blocks of proteins, containing both an amino group and a carboxyl group.

Cohesion: The attraction between molecules of the same substance, often leading to surface tension in liquids.

Monosaccharide: The simplest form of carbohydrates, consisting of a single sugar molecule, such as glucose.

Levels of protein structure: The four levels of organization of a protein molecule, which are primary, secondary, tertiary, and quaternary structures.

Adhesion: The attraction between molecules of different substances.

Disaccharide: A carbohydrate made up of two monosaccharides joined together, such as sucrose.

Surface tension: The elastic tendency of liquids which makes them acquire the least surface area possible, caused by the cohesion of molecules at the surface.

Polysaccharide: A carbohydrate polymer made up of many monosaccharides linked together, such as starch, glycogen, or cellulose.

Specific heat: The amount of heat required to raise the temperature of one gram of a substance by one degree Celsius.

Glycosidic linkage: A type of covalent bond that joins a carbohydrate (sugar) molecule to another group, which may or may not be another carbohydrate.

Solution: A homogeneous mixture composed of two or more substances.

Starch: A polysaccharide made up of glucose units, serving as a major energy storage form in plants.

Ribonucleic acid (RNA): A nucleic acid involved in protein synthesis and the transmission of genetic information in some viruses.

Isotope/Radioactive isotope: Variants of a particular chemical element that differ in neutron number, with radioactive isotopes being unstable and emitting radiation as they decay.

Solvent: The substance in which the solute is dissolved to form a solution.

Glycogen: A polysaccharide that serves as a form of energy storage in animals and fungi.

Half-life: The time required for half of the radioactive atoms in a sample to decay.

Solute: The substance dissolved in a solvent to form a solution.

Cellulose: A polysaccharide that is the main structural component of plant cell walls.

Energy: The capacity to do work or produce heat; exists in various forms such as kinetic, potential, thermal, etc.

Hydrophilic: Having an affinity for water; typically polar or charged molecules.

Chitin: A polysaccharide found in the exoskeleton of arthropods and the cell walls of fungi.

Potential energy: The energy stored by an object due to its position or state.

Hydrophobic: Repelling water; typically nonpolar molecules.

Lipids: A group of organic compounds that are fatty acids or their derivatives, insoluble in water but soluble in organic solvents.

Electron shell: The region around an atom's nucleus where electrons are likely to be found.

Molecular mass: The sum of the masses of all the atoms in a molecule.

Saturated fat: A type of fat containing only single bonds between carbon atoms, typically solid at room temperature.

Valence electron/Valence shell: Electrons in the outermost shell of an atom that are involved in chemical bonding.

Unsaturated fat: A type of fat containing one or more double bonds between carbon atoms, typically liquid at room temperature.

Chemical bonds: The forces that hold atoms together in a compound.

pH: A scale used to measure the acidity or basicity of a solution, with 7 being neutral, below 7 acidic, and above 7 basic.

Fat: A type of lipid that is solid at room temperature, composed of glycerol and fatty acids.

Acid: A substance that donates protons (H⁺ ions) in a solution, typically having a pH less than 7.

Oil: A type of lipid that is liquid at room temperature.

Base: A substance that accepts protons (H⁺ ions) in a solution, typically having a pH greater than 7.

Fatty acid: A long hydrocarbon chain with a carboxyl group at one end, found in fats and oils.

Molecule: A group of atoms bonded together, representing the smallest fundamental unit of a chemical compound.

Organic compound: A compound that contains carbon and is found in living organisms.

Hydrocarbon: An organic compound consisting entirely of hydrogen and carbon.

Phospholipid: A type of lipid that is a major component of cell membranes, composed of two fatty acids, a phosphate group, and a glycerol molecule.

Double Helix- The twisted ladder shape of DNA, where two strands are wound around each other.

Covalent Bond- A bond where two atoms share electrons.

Acid- A substance that donates hydrogen ions (H⁺) and has a pH less than 7.

Oil- A liquid fat that doesn't mix with water, found in plants and fish.

Antiparallel- The opposite direction of the two strands in DNA.

Polar Covalent Bond- A bond where electrons are shared unevenly, creating a slight charge on each end.

Base- A substance that accepts hydrogen ions (H⁺) and has a pH greater than 7.

Fatty Acid- A long chain of carbon and hydrogen with a carboxyl group, used to make fats.

Triglyceride- A fat made of one glycerol molecule and three fatty acids.