AP Biology Midterm

• atom: the smallest particle of a chemical element that can exist.
• element: an essential or characteristic part of something abstract
• atomic number: number of protons in an atom's nucleus, which determines the element's chemical properties
• atomic number: the number of protons in the nucleus of an atom, which is equal to the number of electrons in the outermost shell
• proton: a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron.
• neutron: a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
• electron: a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
• isotope: each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element
• isomer: each of two or more compounds with the same formula but a different arrangement of atoms in the molecule and different properties.
• ion: an atom or molecule with a net electric charge due to the loss or gain of one or more electrons
• ionic bonding is the electrostatic attraction between oppositely charged ions.
• polar covalent bonds are when electrons are shared between atoms and are non-polar
• non polar covalent bonds are between atoms with different electronegativities
• hydrogen: a colourless, odourless, highly flammable gas, the chemical element of atomic number 1.
• hydrogen bonds are weak bonds between the hydrogen atoms of adjacent molecules
• bonds between water molecules and other water molecules are called hydrogen bonds
• bonds between the oxygen and hydrogen are called polar covalent bonds
• oxidation: the process or result of oxidizing or being oxidized (losing electrons)
• reduction: gain of electrons, loss of oxygen, gain of hydrogen, loss of hydrogen
• oxidation-reduction reactions: reactions in which electrons are transferred between atoms or molecules
• cohesion: the tendency of water molecules to stick together, which is important for maintaining the shape of a cell
• adhesion: water molecules stick to the surface of the cell membrane
• capillary action is the force of water moving up a surface due to the pressure of the water
• surface tension is the force applied to separate water molecules
• specific heat capacity is the amount of energy needed to raise the temperature of 1kg of a substance by 1 degree (high in water)
• freezing and expansion of water: water molecules are attracted to each other and form a strong hydrogen bond
• hydrophobic: tending to repel or fail to mix with water.
• hydrophilic: having a tendency to mix with, dissolve in, or be wetted by water.
• amphipathic: (of a molecule, especially a protein) having both hydrophilic and hydrophobic parts.
• pH: a figure expressing the acidity or alkalinity of a solution on a logarithmic scale on which 7 is neutral, lower values are more acid and higher values more alkaline. The pH is equal to −log₁₀c, where c is the hydrogen ion concentration in moles per litre.
• alkaline: having the properties of an alkali, or containing alkali; having a pH greater than 7
• acidic: having the properties of an acid, or containing acid; having a pH below 7.
• Hydrogen ions are H+ ions, which are protons that are lost from the cell.
• hydroxide ions: OH- ions, found in water, are the most common ion in the body
• structural isomers: two or more compounds that have the same molecular formula but different structural formulas
• carboxyl: of or denoting the acid radical —COOH, present in most organic acids
• amino: the group —NH₂, present in amino acids, amides, and many amines
• ketone: an organic compound containing a carbonyl group =C=O bonded to two hydrocarbon groups, made by oxidizing secondary alcohols. The simplest such compound is acetone.
• hydroxyl: of or denoting the radical —OH, present in alcohols and many other organic compounds
• carbohydrates: sugar, C6H12O6