Amino acids, proteins

Question 1

L amino acid correspond to

Answer 1

S configuration (except cysteine)

Question 2

what side is amino group on for an L amino acid

Answer 2

Left

Question 3

nonpoar

Answer 3

glycine, alanine, isoleucine, leucine, methionine, vaine and proline

tryptophan and phenylalanine

Question 4

what is the nonpolar aa that i always forget

Answer 4

proline ( structurally nonpolar)

Question 5

aromatic amino acids

Answer 5

tryptophan (2 ring- typically non-polar), phenylalanine, and tyrosine (polar)

Question 6

polar side chains

Answer 6

serine, threonine, glutamine, asparagine, cysteine

Question 7

asparagine or glutamine longer

Answer 7

glutamine ( later in the alphabet)

they are both amides

Question 8

whats unique about the amide groups of glutamine and asparagine

Answer 8

they do not gain or lose a proton with changes in ph

Question 9

histidine at physiological ph

Answer 9

its side chain has pka of 6 so at physiological pH it is neutral, need to be in more acidic enviroment and second

at pH 0 = +2 ph 4= +1, ph 6= 0 ph 10= -1

Question 10

strongly hydrophobic

Answer 10

A, I, L, V, F (FAIL V) found in inside

Question 11

hydrophilic

Answer 11

charged - H, R (arginine), K (lysine)

glutamate (E), and aspartate (D)
glutamine (Q) and asparagine (N)

Question 12

glutamate

Answer 12

E

Question 13

aspartate

Answer 13

D

Question 14

Q

Answer 14

glutamine

Question 15

N

Answer 15

asparagine

Question 16

K

Answer 16

lysine

Question 17

W

Answer 17

tryptophan

Question 18

Y

Answer 18

tyrosine

Question 19

peptide bond

Answer 19

amide bond- condensation or acyl subsitution rxn

amino is Nu and attaches tha carbonyl carbon, then hydroxy group is kicked off = amide bond

Question 20

cystine

Answer 20

has a sulfur bone

Question 21

high electron affinity means

Answer 21

large amount of heat released when an atom gains an electron - means large delta G (halogens are the most)

Question 22

hesses law

Answer 22

energy is a state variable
energy change is independent of path
so use this is you know the delta H of formations of all reactants and products

delta H of rnx= sum of delta Hf of produucts - sum of delta H reactants

Question 23

what do i have to remeber to do when using hesses law

Answer 23

that the delta H f is given per mol of substance so need to multiple by the mols in reaction - make sure balanced

Question 24

in a concentration cell, where is the concentration greater at the beggining? example Ni 2+

Answer 24

since electrons travel anode to cathode

there would have to be more cations at the cathode bc electrons will run unitil in equilibrium

Question 25

do bacteria and aercha have nucleus?

Answer 25

no they have no nucleus or membrane-bound organeles - they have circular DNA bacteria has peptidlglycan cell wall aercha does not!

Question 26

desmosomes vs tight junctions vs gap junctions

Answer 26

desomsomes- tensile strength by anchoring cytoskeleton -specifically the intermediate filaments together (found in skin with high levels of mechanical stress) tight= prevent water and solutes from dissolving through- serve as a barrier gap= mediate communication

Question 27

reducing and non-reducing SDS-page

Answer 27

reducing means that a reducing agent is added - this can break disulfide bonds- so peptides will seperate into individual peptides if compare reducing and nonreducing sds-page can see if a protein had covalent bond (disulfide bonds)

Question 28

when does ATP come to muscle contraction

Answer 28

right after power stoke ( ATP binds after release the myosin head) ATP hydrolysis for the energy needed to pull myosin back to high energy position ( so it is ready for another stroke) when Ca enters myosin can bind ADP +P is released and power stoke happens