Flashcards in Chapter 1 Terms Deck (24):
Large molecules such as proteins and amino acids.
Low-molecular-weight molecules such as glucose and glycerol.
Stores genetic information in all cellular organisms.
Deoxyribonucleic acid (DNA)
The macromolecules that are key participants in most biological process.
Comprises all multicellular organisms including human beings as well as many microscopic unicellular organisms such as yeast. The defining characteristic is the presence of a well-defined nucleus within each cell.
Unicellular organisms which lack a nucleus. Also referred to as prokaryotes.
Bacteria-like organisms that are biochemically quite distinct from other previously characterized bacterial species.
The structure that is composed of 2 intertwined strands arranged such that the sugar-phosphate backbone lie on the outside and the bases on in the inside.
These are the strongest of bonds. They are formed by the sharing of a pair of electrons between adjacent atoms. They hold the atoms together within the individual bases.
These structures depict alternative arrangements of single and double bonds that are possible within the same structural framework. Structures are shown connected by a double-headed arrow.
A charged group on one molecule can attract an oppositely charged group on another molecule.
These bonds are much weaker and somewhat longer than covalent bonds and are essentially electrostatic interactions. These interactions are responsible for specific base pairing in the DNA double helix.
The distribution of electronic charge around an atom fluctuates with time. At any instant, the charge distribution is not perfectly symmetric.
van der Waals interaction
Water molecules in contact with nonpolar molecules form "cages" around them, becoming more well-ordered than water molecules free in solution.
These interactions of nonpolar molecules with water molecules are not as favorable as are interactions between the water molecules themselves.
A measure of the degree of randomness or disorder in a system.
The heat content of a system.
An accounting tool that keeps track of both the entropy of the system (directly) and the entropy of the surroundings (in the form of heat released from the system).
Gibbs free energy
The concentration of hydrogen ions in solution. It is specifically defined as -log[H+].
The concentration of the deprotonated form of the group or molecule is equal to the concentration of the protonated form; the deprotonation process is halfway to completion. Thus pH equals this.
Solutions that resist changes in pH.
The 20 building blocks which proteins are built of.
The relation that links the DNA sequence to the encoded protein sequence.