Biological Molecules and Enzymes

Question 1

allosteric activators

Answer 1

binds to the enzymes at a site other than the active site as well as changes the shape of the substrate

Question 2

allosteric inhibitors

Answer 2

binds to the enzymes at a site other than the active site and the substrate can’t bind

Question 3

adipocytes

Answer 3

types of fat cells that have a cytoplasm containing only triglycerides

Question 4

amphipathic

Answer 4

hydrophilic and hydrophobic properties

Question 5

Cofactors

Answer 5

help enzymes reach their optimal activity

Question 6

Coenzymes

Answer 6

are organic molecules that act as cofactors and help catalyze reactions

Question 7

Enzyme substrate complex

Answer 7

this forms when the enzyme binds to the substrate

Question 8

Fat soluble vitamins

Answer 8

vitamins are transported in the body with the fats from one’s diet to help the absorption of said fats; examples are Vitamin A,D,E,K

Question 9

glycogen

Answer 9

a polymer of glucose that contains alpha linkages. found in all animal cells but mostly in the liver and muscle cells

Question 10

Irreversible inhibitors

Answer 10

agents that bind irreversibly to enzymes and interrupt its function

Question 11

Km

Answer 11

refers to how high the concentration of the substrate must be to speed up the reaction

Question 12

mixed inhibitors

Answer 12

bind at a site other than the active site; they can bind to either the enzyme alone or the enzyme-substrate complex

Question 13

negative cooperativity

Answer 13

the first substrate changes the shape of the enzyme but makes the following substrates more difficult to bind

Question 14

positive cooperativity

Answer 14

the first substrate changes the shape of the enzyme, thus making the following substrates more easily able to bind

Question 15

noncompetitive inhibitors

Answer 15

a type of mixed inhibitor that bind noncovalently to an enzyme at a site other than the active site, thus changing the shape of the enzyme

• no change on Km
• lower Vmax

Question 16

oxidoreductases

Answer 16

catalyze the transfer of electrons or hydrogen ions

Question 17

transferases

Answer 17

catalyze reactions in which groups are transferred from one place to another

Question 18

hydrolases

Answer 18

regulate hydrolysis

Question 19

lyases

Answer 19

catalyze reactions in which functional groups are added to double bonds or vice versa

Question 20

isomerases

Answer 20

catalyze the transfer of groups within the molecule with the motive of creating isomers

Question 21

ligases

Answer 21

catalyze condensation reactions along with hydrolysis of High energy molecules

Question 22

prostaglandins

Answer 22

a group of lipids that are made at the site of tissue damage and infection to resolve injury

Question 23

sphingolipids

Answer 23

• have a long fatty acid chain and polar heads
• backbone is amino alcohol called sphingosine
  these compounds make up part of the cell membrane

Question 24

starch

Answer 24

a type of long term storage that comes in two forms: amylose and amylopectin

Question 25

steroids and example

Answer 25

- a type of lipid with a four-ringed structure | - main example cholesterol

Question 26

cholesterol

Answer 26

maintains membrane stability and fluidity as well as acts as a precursor for steroid hormones

Question 27

amylose

Answer 27

form of starch - branched or unbranched but has same alpha linkages as glycogen

Question 28

amylopectin

Answer 28

form of starch - resembles glycogen but differs in branching structure

Question 29

uncompetitive inhibitors

Answer 29

bind to a site other than the active site and once it is bound, the substrate remains associated with that enzyme. - Km decreases because affinity for substrate increases - Vmax decreases because substrate is bound to enzyme for long time

Question 30

competitive inhibitors

Answer 30

binds reversibly to the active site using NON COVALENT bonds and only for a quick second. - Km increases - Vmax does not change - the concentration of the substrate can be increased in order to overcome inhibition

Question 31

Zymogen

Answer 31

inactive forms of enzymes that can become irreversibly activated by a change in the environment or other enzymes

Question 32

cytochromes and example

Answer 32

proteins that need to have a prosthetic heme group to function - example is hemoglobin

Question 33

what is the major function of a phospholipid

Answer 33

serve as a structural component of membranes

Question 34

what is the major function of triacylglycerols

Answer 34

store metabolic energy and provide thermal insulation and padding

Question 35

what is the major function of steroids

Answer 35

regulate metabolic activities

Question 36

what is the structure of waxes

Answer 36

formed by an ester linkage between a long chain alcohol and a long chain fatty acid

Question 37

what is an advantage of long carbon chains

Answer 37

energy storage

Question 38

describe eicosanoids and its three examples mentioned in the book

Answer 38

a class of lipids -> released from cell membranes as hormones that regulate BP, body temperature and smooth muscle contraction examples -> prostaglandins, thromboxanes and leukotrienes

Question 39

what is the important substitution in sickle cell disease

Answer 39

an acidic glutamate is replaced with a non polar valine -> causes hemoglobin to polarize

Question 40

what are the five forces that contribute to the tertiary structure

Answer 40

covalent disulfide bonds, ionic interactions, hydrogen bonds, van der Waals forces and hydrophobic side chains

Question 41

what are the two types of coenzymes

Answer 41

cosubstrates and prosthetic groups

Question 42

what makes an inhibitor competitive

Answer 42

when the inhibitor binds to the enzyme's active site

Question 43

what makes an inhibitor noncompetitive

Answer 43

when the inhibitor binds to the enzyme alone or enzyme-substrate complex with the same affinity

Question 44

what makes an inhibitor uncompetitive

Answer 44

when the inhibitor only binds to the enzyme-substrate complex

Question 45

define the primary structure of proteins

Answer 45

number and sequence of amino acids

Question 46

define the secondary structure of proteins

Answer 46

when the single chain forms into distinct shapes -> twist into alpha helices or beta sheets

Question 47

define tertiary structure of proteins

Answer 47

three dimensional shape formed by folds of the chain

Question 48

define the quaternary structure of proteins

Answer 48

two or more polypeptide chains bind together

Question 49

an enzyme with its cofactor is called....

Answer 49

holoenzyme

Question 50

an enzyme without its cofactor is called...

Answer 50

apoenzyme