Foundations 1

Question 1

four major classes of biomolecules (and what biopolymers/supramolecular assemblies they compose)

Answer 1

amino acids (proteins, ribosomes) carbohydrates (polysaccharides). nucleotides (nucleic acids, chromatin). lipids (membranes)

Question 2

identifying features of an amino acid

Answer 2

carboxylic acid with an amino group on the same (alpha) carbon atom

Question 3

carbohydrate: identifying features

Answer 3

C(H2O)n with many hydroxyl groups

Question 4

identifying features of nucleotides

Answer 4

nitrogenous base (Aromatic) + inorganic phosphate (Pi) + sugar

Question 5

types of bonds between amino acids, nucleotides and monosaccharides

Answer 5

peptide bonds, phosphodiester bonds, and glycosidic bonds respectively ** ALL are covalent **

Question 6

primary structure definition + type of bond

Answer 6

sequence of monomers linked by covalent bonds

Question 7

secondary and tertiary structure definition + type of bonds

Answer 7

higher levels of structure (3D folding) of biopolymers. depend entirely on non covalent bonds between atoms (ionic, hydrogen bonds, van der waals interactions)

Question 8

covalent bonds: involved in? electrons?

Answer 8

building the monomers and polymers - electrons shared by two atoms

Question 9

ionic bonds vs. hydrogen bonds vs. van der waals interactions

Answer 9

IB: oppositely charged groups; in large numbers. H: special dipole interaction from differences in electronegativity. VdW: weak dipole and London dispersion forces

Question 10

salt bridges: definition, aka?

Answer 10

ionic interactions between constitutively charged groups at physiological pH aka ionic interactions

Question 11

examples of salt bridges

Answer 11

amino acids (charged side chain), DNA (charged phosphodiester back bone)

Question 12

water: number of H bonds

Answer 12

four H bonds, 2 as a donor and 2 as acceptor

Question 13

ice: structure?

Answer 13

crystalline lattice structure (each water molecule forms 4 hydrogen bonds)

Question 14

water is a highly ____ liquid. behave in a way that maximizes?

Answer 14

cohesive: maximizes their interactions with each other (max entropy) and results in the hydrophobic effect

Question 15

hydrophobic effect results from? what does it entail?

Answer 15

thermodynamic principles which ensure that the number of H bonds among the water molecules is maximized. non polar molecules like lipids can’t interact with water so are excluded

Question 16

protein: definition

Answer 16

polymer (polypeptide) made up of amino acids joined by peptide bonds

Question 17

examples of protein functions (5)

Answer 17

structure, movement, catalysis, transport, communication

Question 18

two different classes of protein by morphology

Answer 18

globular (have tertiary and sometimes quaternary structures - enzymes, transporter proteins, receptors). fibrous: form rod or wire like shapes usually for connective tissues or muscle fibers

Question 19

what level of structure is stabilized by covalent bonds

Answer 19

only the primary structure

Question 20

side chains and secondary structure

Answer 20

side chains aren’t involved - only between backbone