Chem Ch 16 Proteins

Front 1

what are proteins?

Back 1

large molecules consisting of many amino acids linked together by amide bonds

Front 2

what two functional groups do proteins always consist of?

Back 2

carboxylic acids

amine

Front 3

how many naturally occurring amino acids are found in the body?

Back 3

20

Front 4

what causes amino acids to differ?

Back 4

by change in their R group. they are classified by their R group

Front 5

what 4 ways can proteins be classified?

Back 5

polar

nonpolar

acidic

basic

Front 6

nonpolar amino acids

Back 6

–glycine, alanine, valine, leucine,isoleucine, phenylalanine, proline, and methionine

Front 7

polar amino acids

Back 7

–serine, threonine, tyrosine,tryptophan, cysteine, asparagine, and glutamine

Front 8

acidic amino acids

Back 8

–aspartic acid (aspartate) andglutamic acid (glutamate)

Front 9

basic amino acids

Back 9

–histidine, lysine, and arginine

Front 10

all amino acids except ____ are chiral

Back 10

glycine

Front 11

which amino acids are found in animal proteins

Back 11

only L-amino acids

Front 12

zwitterion

Back 12

has a negative and a positive charge; net charge of zero

Front 13

amino acids are ______ compounds

Back 13

ionic

Front 14

in solution, when the number of negative charges is equal to the number of positive charges, this is known as ______

Back 14

isoelectric point (net charge of zero)

Front 15

amino acids are amphiprotic (act as acids and bases) and act as_____

Back 15

buffers

Front 16

dipeptide

Back 16

formed when the carboxyl group of one amino acid reacts with the amino group of another amino acid to form an amide (peptide bond).

Front 17

N-terminal residue

Back 17

an amino acid on the end of the chain that has an unreacted amino group

Front 18

C-terminal residue

Back 18

an amino acid on the end of the chain that has an unreacted carboxylate group

Front 19

tripeptides

Back 19

3 amino acids

Front 20

polypeptides

Back 20

up to 50 amino acids

Front 21

proteins

Back 21

more than 50 amino acids

Front 22

what are functions of proteins?

Back 22

Catalysis, structure, storage, protection, regulation, nerve impulse, movement, transport,

Front 23

classification of proteins based on structure:

Back 23

fibrous and globular

Front 24

fibrous proteins

Back 24

made up of long rod-shaped or string-like that intertwine to form strong fibers (collagen)

Front 25

globular proteins

Back 25

spherical protein that usually forms stable suspensions in water or dissolves in water (myoglobin)

Front 26

classification of proteins based on composition:

Back 26

simple and conjugated

Front 27

simple proteins

Back 27

only one amino acid

Front 28

conjugated proteins

Back 28

contain amino acid groups along with organic and inorganic components

Front 29

how many levels of organization are there to the structure of a protein?

Back 29

4

Front 30

primary structure

Back 30

the amino acid sequence of a structure

Front 31

what determines the biological function of a protein?

Back 31

the sequence/order of the amino acids

Front 32

how do you determine the amount of different isomer sequences possible in a protein?

Back 32

factorial rule

(7x6x5x4....)

Front 33

how many different tripeptides can be made from 20 amino acids

Back 33

20x20x20 =8000

20^n where n is the length of the chain

Front 34

secondary structure

Back 34

short-range interactions that produce repeating patterns such as the alpha helix or beta pleated sheet structure. held together by intramolecular hydrogen bonds

Front 35

who developed the alpha helix structure and won a nobel prize?

Back 35

linus pauling

Front 36

tertiary structure

Back 36

long-range interactions that stabilized the overall 3D conformation of a protein. interactions are between the R groups of the amino acids

Front 37

what are the 4 types of R group interactions that stabilize the the protein structure?

Back 37

1. hydrogen bonding

2. covalent bonds

3. salt bridges

4. hydrophobic interactions

Front 38

covalent bonds

Back 38

disulfide linkages between two cysteine amino acids

Front 39

hydrogen bonding

Back 39

between two polar amino acids

Front 40

salt bridges

Back 40

between acidic and basic amino acids with oppositely charged side chains

Front 41

hydrophobic interactions

Back 41

between non polar side amino acids

Front 42

quaternary structure

Back 42

involves the clustering of several individual protein chains to a larger specific shape (hemoglobin)