Chapter 3 Protein Structure and Folding

Question 1

20 distinct building blocks of proteins (actually 22)

Answer 1

amino acids

Question 2

the central carbon on an amino acids binds to these 4 structures:

Answer 2

H - hydrogen atom
NH2 - amino functional group
COOH - carboxyl group
distinctive “R” group, or side chain

Question 3

in water, amino acids…

Answer 3

ionize

Question 4

in water, the carboxyl group on an amino acid…

Answer 4

acts as an acid

Question 5

in water, the amino group on an amino acid…

Answer 5

acts as a base

Question 6

what makes the 20 amino acids unique from each other? Why?

Answer 6

the distinct R group, or side chain

it causes variation in properties

Question 7

properties of polar and electrically charged R groups:

Answer 7

interact readily with water and are hydrophilic, dissolve readily in water

Question 8

properties of non-polar R groups:

Answer 8

lack highly electronegative atoms capable of reacting with water
hydrophobic, coalesce in aqueous solution instead of dissolving

Question 9

if the R group has a negative charge:

Answer 9

it is acidic and will lose a proton

Question 10

if the R group has a positive charge:

Answer 10

it is basic and will pick up a proton

Question 11

building blocks of polymers

Answer 11

monomers

Question 12

if the R group is uncharged
A. with an oxygen
B. without an oxygen

Answer 12

A. the electronegative oxygen will form a covalent bond within the R group, making it an uncharged polar amino acid
B. its a non polar amino acid

Question 13

meaning of monomer

Answer 13

one part

Question 14

macromolecules

Answer 14

large molecules made up of smaller molecule subunits joined together, made up of monomers

Question 15

monomers linking together:

Answer 15

polymerization

Question 16

amino acids are the ______ that polymerize to form _____

Answer 16

monomers, proteins

Question 17

monomer in, water out, occurs in a ________ reaction

Answer 17

condensation

Question 18

water in, monomer out, occurs in a ________ reaction

Answer 18

hydrolysis

Question 19

monomers polymerize through what type of reaction?

Answer 19

condensation reactions/dehydration reactions

Question 20

polymerization

Answer 20

bonding together of monomers

Question 21

bond between the amino group and the carboxyl group of two acids

Answer 21

peptide bond

Question 22

R group orientation in the peptide backbone:

Answer 22

the R groups extend out from the back bone, can react with other R groups and water

Question 23

directionality in the peptide backbone:

Answer 23

amino group on one end (N terminus), carboxyl group on one end (C terminus)

Question 24

flexibility in the peptide backbone:

Answer 24

the bond on either side of the peptide bond can rotate, so the molecule is flexible

Question 25

polymer with less then 50 amino acids

Answer 25

oligopeptide, or peptide

Question 26

oligopeptide

Answer 26

few peptides

Question 27

polymer with mire than 50 peptides

Answer 27

polypeptides

Question 28

polypeptides

Answer 28

many peptides

Question 29

proteins are ____ made up of _________

Answer 29

proteins are polymers made up of amino acids

Question 30

Primary structure of proteins is determined by ____ and ______

Answer 30

peptide bonds and the unique sequence of amino acids that make up the protein

Question 31

Changes in primary structure affect:

Answer 31

protein function

Question 32

Types of bonds that support secondary structure?

Answer 32

hydrogen bonds

Question 33

two possible secondary structures:

Answer 33

alpha helicies and beta pleated sheets

Question 34

a proteins 3 dimensional shape is determined by its:

Answer 34

tertiary structure

Question 35

5 types of bonds that affect tertiary structure

Answer 35

1. hydrogen bonding
2. hydrophobic interactions
3. van der waals interactions
4. covalent bonding (disulfide bonds)
5. Ionic Bonding (between charged groups)

Question 36

A combination of polypeptide subunits results in:

Answer 36

quaternary structure

Question 37

macromolecular machines

Answer 37

groups of multiple proteins that assemble to carry out a function

Question 38

dimer

Answer 38

protein consisting of 2 identical polypeptide subunits

Question 39

tetramer

Answer 39

protein consisting of 2 sets of identical polypeptide subunits

Question 40

how are folding and function related? what happens when a protein is denatured?

Answer 40

folding is crucial to function, denaturing a protein breaks disulfide and hydrogen bonds and keeps proteins from working properly

Question 41

which proteins facilitate protein folding?

Answer 41

molecular chaperones

Question 42

do proteins only have one shape?

Answer 42

no, proteins are somewhat flexible and dynamic, until they are prompted into their functional form

Question 43

Stanley Prusiner on protein folding

Answer 43

some proteins are induced to fold into disease causing , infectious agents called prions

Question 44

side effect of prions in several mammals

Answer 44

brain degeneration

Question 45

proteins that catalyze are called:

Answer 45

enzymes

Question 46

proteins that attack and destry viruses are called:

Answer 46

antibodies

Question 47

_____ _______ are responsible for the movement of the cell, and moving large molecules within the cell

Answer 47

motor proteins

Question 48

proteins are involved in ________ from cell to cell around the body

Answer 48

carrying and receiving signals

Question 49

_______make up body component like skin and nail and form the internal skeleton of cells

Answer 49

structural proteins

Question 50

catalyzed reactions involve one or more reactants called :

Answer 50

substrates

Question 51

enzymes hold substrates in the exact orientation…

Answer 51

to that they can react

Question 52

Emil Fischer’s idea

Answer 52

lock and key model of enzymes and substrates

Question 53

where substrates bind to enzymes is the:

Answer 53

active site