Ch. 20 Chemistry

Front 1

what is the role of structural proteins?

Back 1

tendons, cartilage, hair, nail

Front 2

What is the role of contractile proteins?

Back 2

muscles

Front 3

What is the role of transport proteins?

Back 3

hemoglobin

Front 4

What is the role of storage proteins?

Back 4

milk

Front 5

What are proteins made up of?

Back 5

polymer amino acids

Front 6

What does amino acids contain of what functional group?

Back 6

-carboxylic acid group and an amino group on the alpha carbon
-Side group R gives unique characteristics

Front 7

how do you classify amino acids?

Back 7

Nonpolar
-an amino acid that contains a nonpolar side chain
-R = H, CH3, alkyl groups, aromatic
Polar
-an amino acid with a side chain that is polar but neutral
-polar groups with -O-, -SH, -N-

Front 8

How do you classify polar/acidic amino acids?

Back 8

-an amino acid that contains a second carboxyl group in its side chain
-R = -CH2COOH, or -COOH

Front 9

How do you classify polar/basic amino acid?

Back 9

-an amino acid that contain a second amino group in it side chain
- R= -CH2Ch2NH2

Front 10

What are the 10 amino acids not synthesized by the body but is essential amino acid in your diet?

Back 10

Arg, His, Ile, Leu, Lys, Met, Phe, Thr, Trp, Val

Front 11

What amino acid is not chiral in Fischer projections of amino acids?

Back 11

Glycine

Front 12

What is the Fischer Projections of amino acids?

Back 12

-All amino acids except glycine are chiral
-amino acids have stereoisomers
-in biolgical systems, only L amino acids are used in proteins

Front 13

In Zwitterions, Ionization of the -NH2 and the -COOH group becomes what?

Back 13

- -COOH loses a proton (ACID)
- -NH2 gains a proton (BASE)

Front 14

what are the rules of Zwitterion?

Back 14

-has both a+ and -charge
-neutral overall
-ionization -COOH loses a proton (acid)
-ionization of -NH2 gains a proton (base)

NH2-CH2-COOH (glycine)------>H3+N-CH2-COO- (Zwitterion of glycine)

Front 15

What is the rule of PH and ionization of amino acid?

Back 15

-acidic amino acids such as aspertic acid have a second a carboyxyl group that can donate and accept protons
-whether a group is ionized or not depends on its pKa

Front 16

in pH and ionization, amino acids with ionizable side chains have how many forms in solution?

Back 16

4 forms in solution
- -Cys, Tyr, Lys, Arg, His, Asp, Glu

Front 17

What is deprotonated and protonated?

Back 17

-if pH>pKa, the group has been deprotonated
-If pH< pKa, the group is protonated

Front 18

Steps of Ionization of amino acids?

Back 18

1. draw amnio acid in the fully protonated form
-low pH
-all acid groups are protonated
(-COOH)
-all amino acids are protonated
(-NH3+)
2. identify the protons that will come off (and the order in which they will come off)
3. take the protons off 1 by 1

Front 19

How does electrophoresis separate amino acids?

Back 19

according to their charges
-positively charged amino acids move towards the negative electrode
-negatively charged amino acids move toward the positive electrode
-netural amino acids will not move in either direction

Front 20

how are amino acids visualized in electrophoresis?

Back 20

as separate bands on filter paper or thin layer plate

Front 21

What is Peptide bond?

Back 21

amide bond formed by the carboxylate group of an amino acid and the amino group the next amino acid

Front 22

What is a polypeptide containing 50 or more amino acids?

Back 22

protein

Hint 22

slide 25

Front 23

What are the different ways to describe the structure of a protein?

Back 23

1. primary structure
2. secondary structure
3. tertiary structure
4. quaternary structure

Hint 23

slide 25

Front 24

What is primary structure protein?

Back 24

-n-terminus on left
-c-terminus on right

Hint 24

slide 25

Front 25

What is secondary structure protein?

Back 25

-three dimensional arrangement of amino acids with the polypeptide chain in a corkscrew shape
-held by H bonds between the H of -N-H group and the -O of C=O of the fourth amino acids along the chain
-looks like a coiled "telephone cord"
-geometrical orientation of polypeptide chains

Hint 25

slide 26

Front 26

What is tertiary structure protein?

Back 26

-overall shape of a protein
-results from cross-links between R groups of amino acids in chain
-disufide -S-S-
-ionic -COO- H3+N-
-H bonds C=O HO-
-hydrophobic -CH3 H3C-


-"covalent bond"

Hint 26

slide 27

Front 27

what is the 2 main kinds of secondary structure?

Back 27

1. alpha helices
2. beta pleated sheets

Hint 27

slide 31

Front 28

What is disulfide bonding?

Back 28

cysteine residues can form in two different ways
-between two SH groups on the same chain
-between two SH groups on different chains

Hint 28

slide 38

Front 29

What has both intrachain and interchain disulfide linkages as part of its tertiary structure?

Back 29

human insulin

Hint 29

slide 39

Front 30

What is a conjugated protein?

Back 30

has a prosthetic group

Hint 30

slide 43

Front 31

What is quaternary structure?

Back 31

-proteins with two or more chains (multliple chains)
-example: hemoglobin
-carries oxygen in blood
-four polypeptide chains
-each chain has a heme group to bind oxygen
-a conjugated protein (has a prosthetic group)

Hint 31

slide 43
41:08

Front 32

What does wiping the skin with alchohol do?

Back 32

-disrupts membrane and protein

Hint 32

slide 53
50:27

Front 33

What is the applications of denaturation?

Back 33

1. hard boiling an egg
2. wiping hte skin with alchohol swab for injection
3. cooking food to destroy E.coli
4. heat used to cauterize blood vessels
5. autoclave sterilized instruments
6. milk is heated to make yogurt

Hint 33

slide 53

Front 34

Differences between globular and fibrous proteins?

Back 34

Globular protiens
-spherical shape
-water soluble
-multiple types of secondary structure
-transport, metabolism
-more numerous Ex: inslulin, hemoglobin, enzymes, antibodies
Fibrous proteins
-long, thin fibers
-not water soluble
-1 type of secondary structure
-strength, protection
-few in the body Ex: hair, wool, skin, nails

Hint 34

slide 45

Front 35

What is required to hydrolysis a protein?

Back 35

acid or base, water and heat

Front 36

What is protein hydrolysis similar to?

Back 36

digestion of proteins using enzymes

Front 37

Where does protein hydrolysis occur?

Back 37

in cells to provide amino acids to synthesize other proteins and tissue

Front 38

What is proteins hydrolysis?

Back 38

break down of peptide bonds

Front 39

In solution, pH and ionization forms three different amino acids. What are they?

Back 39

positive ion, negative ion, and zwitterion