Chapter 1 Flashcards
What are the two different classes of molecules?
biological macromolecules and metabolites
What are biological macromolecules?
large molecules such as proteins and nucleic acids
What are metabolites?
low-molecular-weight molecules such as glucose and glycerol
What is the main function of DNA?
store genetic information in all cellular organisms
Proteins
the macromolecules that are key participants in most biological processes that are built from 20 building blocks of amino acids
What are the three domains of organisms?
Eukarya, Archaea, Bacteria
Eukarya
comprise all multicellular organisms; well-defined nucleus
Prokaryotes
unicelluar organisms lacking a nucleus
Archaea
organisms having diverged from bacteria
DNA
deoxyribonucleic acid: a linear polymer made up of four different types of monomers
DNA is polar or nonpolar?
polar
What are the four bases of DNA?
Adenine, Guanine, Cytosine, Thymine
The bases of DNA are held together by what bond interactions?
covalent bonds
Are hydrogen bonds stronger or weaker than covalent bonds?
weaker
The structure of the double helix proposed what two properties of central importance to DNA as hereditary material?
1) the structure is compatible wit any sequence of bases 2) because of base-pairing, the sequence of bases along one strand completely determines the sequence along the other strand
What forces cause two strands of DNA to bind to each other?
Covalent bonds, noncovalent bonds
What are the strongest bond types?
covalent
How is a covalent bond formed?
by the sharing of a pair of electrons between adjacent atoms
T/F. A molecule that can be written as several resonance structures of approximately equal energies has greater stability than does a molecule without multiple resonance structures.
True
What are the four fundamental noncovalent bond types?
1) electrostatic interactions 2) hydrogen bonds 3) van der Waals interactions 4) hydrophobic interactions
Electrostatic interactions
a charged group on one molecule can attract an oppositely charged group on another molecule
The energy of an electrostatic interaction can be given by what law?
Coulomb’s Law: E=kq1q2/Dr^2