unit 5-7

Question 1

what are the physical properties of lipids?

Answer 1

• soluble in an organic solvent, but insoluble in H2O

Question 2

what is an acid?

Answer 2

a positive ion that donates the proton

Question 3

what is a base?

Answer 3

the base is a proton acceptor (anion charged)

Question 4

primary proteins

Answer 4

• sequence of amino acids
• held by peptide bonds
• no folding/interactions between molecules

Question 5

secondary proteins

Answer 5

• local folding of peptide chain into helices (a- helix or b-sheet)
• folding due to hydrogen bonds between the N-H and C=O groups
• 3D

Question 6

tertiary proteins

Answer 6

• 3d folding pattern of a protein due to side-chain interactions
• polar on OUTSIDE
• non polar on INSIDE

Question 7

Quarternary proteins

Answer 7

• protein consisting of more than one amino acid chain
  ex. hemoglobin

Question 8

what are soaps?

Answer 8

salts of carboxylic acids

Question 9

what two parts does soap have?

Answer 9

non polar tail and polar head

Question 10

what are hydrolyzable lipids derived from?

Answer 10

fatty acids

Question 11

what makes up fatty acid?

Answer 11

carboxylic acid head and long carbon chain

Question 12

what do saturated fatty acids have?

Answer 12

no double bonds (single bond)

Question 13

what do unsaturated fatty acids have?

Answer 13

they have double bonds and are generally CIS

Question 14

what are waxes?

Answer 14

esters formed from a fatty acid + high molecular weight alcohol

Question 15

what are triglycerides made up of?

Answer 15

three esters formed from glycerol + 3 fatty acids

Question 16

what does the increase of fatty acid double bonds do to the melting point?

Answer 16

decreases the triacylglycerol melting point

Question 17

what is cholesterol not?

Answer 17

water soluble

Question 18

what two functional groups do amino acids contain?

Answer 18

amino & carboxyl group

Question 19

what is pI?

Answer 19

pH at which our molecule has no net charges

Question 20

what is a zwitterion?

Answer 20

when an amino acid contains both a base and acid (+ and - charge on same molecule)

Question 21

what is a basic amino acid?

Answer 21

lysine

Question 22

what is an acidic amino acid?

Answer 22

asparic acid

Question 23

what is an L- alanine?

Answer 23

amine on left of structure

Question 24

what is a D-alanine?

Answer 24

amine on right of structure

Question 25

when the pH> isoelectric pH, the ammonium cation __ proton, resulting in the amino acid having a ___ charge

Answer 25

lose, negative

Question 26

what is a peptide bond?

Answer 26

COO- of amino acid reacts with NH3 of another amino acid

Question 27

dipeptide

Answer 27

two amino acids joined by 1 amide bond

Question 28

tripeptide

Answer 28

3 amino acids joined by 2 amide bonds

Question 29

London dispersion forces

Answer 29

between two nonpolar molecules (WEAKEST)

Question 30

Hydrogen bonding

Answer 30

between negative dipole and positive dipole (O-H or N-H) SECOND WEAKEST

Question 31

electrostatic interactions

Answer 31

between acidic and basic amino acid side chains (COO- NH3+)

Question 32

disulfide bonds

Answer 32

between two sulfur groups (on cysteines) STRONGEST

Question 33

what are fibrous proteins composed of?

Answer 33

long linear peptide chain

Question 34

fibrous proteins are ____ in water and serve as ___ roles

Answer 34

insoluble, structural

Question 35

what do globular proteins have?

Answer 35

polar outside and non polar inside

Question 36

what are globular proteins in water?

Answer 36

soluble

Question 37

protein denaturing

Answer 37

the process of altering protein shape (NOT breaking peptide bonds)

Question 38

protein hydrolysis

Answer 38

driven by enzyme

Question 39

what is an enzyme?

Answer 39

proteins that serve as biological catalysts for reactions in all living things

Question 40

what is true about enzymes?

Answer 40

- increase rate of reaction but are unchanged - each enzyme catalyzes a certain reaction or type of reaction only

Question 41

what is enzyme activity affected by?

Answer 41

both temperature and pH

Question 42

when there is an increase in temperature, what happens to the rate of a chemical reaction?

Answer 42

increases as well

Question 43

competitive inhibitor

Answer 43

competes with the substrate for binding to the active site

Question 44

noncompetitive inhibitor

Answer 44

binds enzyme at a different location than the active site

Question 45

allosteric control

Answer 45

binding of regulator to a site on an enzyme that affects its ability to bind a substrate at the active site

Question 46

enzyme inhibitors

Answer 46

bind to an enzyme and alter/destroy the enzymes activity to function

Question 47

reversible inhibitor

Answer 47

enzyme activity is restored when drug is removed from the environment

Question 48

irreversible inhibitor

Answer 48

covalently binds an enzyme, the enzyme is permanently disabled