enzymes p2 nucleotides 1,2 finals

Question 1

three types of specificity enzymes

Answer 1

stereochemical, reaction, substrate

Question 2

only one of the isomers which acts as a substrate for an enzyme action

Answer 2

optical specificity

Question 3

specific to only one isomer even if the compound is one type of molecule

Answer 3

stereospecificity

Question 4

one enzyme can catalyze only one of the various reactions

Answer 4

reaction specificity

Question 5

one enzyme catalyzes or acts on only one substrate

Answer 5

absolute specificity

Question 6

enzymes that catalyze similar molecules with the same functional group (trypsin and chymotrypsin)

Answer 6

group specificity

Question 7

observed in proteolytic enzymes, glycosidases, and lipases which act on peptite bonds, glycosidic bonds and ester bonds

Answer 7

bond specificity

Question 8

enzyme is most active on its optimum temperature

Answer 8

effect of temperature

Question 9

enzymatic reaction depends on the pH of the medium

Answer 9

effect of pH

Question 10

enzymatic reaction is directly proportional to the enzyme concentration

Answer 10

effect of enzyme concentration

Question 11

products formed as a result of enzymatic reaction may accumulate, and this excess of product may lower the enzymatic reaction by occupying the active site of the enzyme.

Answer 11

effect of product concentration

Question 12

reaction is directly proportional to the substrate concentration, but only true up to a certain concentration after which the increasing concentration of substrate does not further increase the velocity of the reaction

Answer 12

effect of substrate concentration

Question 13

Certain enzymes is dependent on metal ion activators and coenzymes

Answer 13

effect of activators and coenzyme

Question 14

Whenever the active site is not available for binding of the substrate, the enzyme activity may be reduced.

Answer 14

effect of modulators and inhibitors

Question 15

Time required for completion of an enzyme reaction increases with decreasing temperature from its optimum.

Answer 15

effect of time

Question 16

the lock is the enzyme and the key is the substrate. Only the correctly sized key (substrate) fits into the key hole (active site) of the lock (enzyme

Answer 16

lock-and-key model

Question 17

he postulated the lock-and-key model in 1894

Answer 17

Emil Fischer

Question 18

the substrate plays a role in determining the final shape of the enzyme and that the enzyme is partially flexible.

Answer 18

induced fit model

Question 19

he created the induced fit model in 1958

Answer 19

Daniel E. Koshland, Jr.

Question 20

These enzymes contains active sites with catalytic residues that can form temporary covalent bonds with the substrate molecules.

Answer 20

covalent catalysis

Question 21

These implies that for the reaction to occur, they must be close enough and must also have the proper orientation.

Answer 21

catalysis by proximity and orientation

Question 22

Active sites may contain residue such as histidine that can participate in hydrogen ion transfer.

Answer 22

acid-base catalysis

Question 23

Metal atoms such as Zinc, Magnesium and Iron are used as cofactors by a multitude of different enzymes.

Answer 23

metal-ion catalysis

Question 24

Rates of enzyme-catalyzed reactions can be decreased by a group of substances called inhibitors.

Answer 24

enzyme inhibition

Question 25

is a substance that slows or stops the normal catalytic function of an enzyme by binding to it

Answer 25

enzyme inhibitor

Question 26

is a molecule that sufficiently resembles an enzyme substrate in shape and charge distribution that it can compete with the substrate for occupancy of the enzyme’s active site

Answer 26

competitive enzyme inhibitor

Question 27

When a competitive inhibitor binds to the enzyme active site, inhibitor remains unchanged (no reaction occurs), but its physical presence at the site prevents a normal substrate molecule from occupying the site – result is decrease in enzyme activity.

Answer 27

reversible competitive inhibition

Question 28

is a molecule that decreases enzyme activity by binding to a site on an enzyme other than the active site

Answer 28

noncompetitive enzyme inhibitor

Question 29

substrate can still occupy the active site, but the presence of the inhibitor causes a change in the structure of the enzyme sufficient to prevent the catalytic groups at the active site from properly effecting their catalyzing action

Answer 29

reversible noncompetitive inhibition

Question 30

Occurs when (II) binds only to the enzyme- substrate complex (ESES) and not free EE.

Answer 30

uncompetitive inhibition

Question 31

is a molecule that inactivates enzymes by forming a strong covalent bond to an amino acid side-chain group at the enzyme’s active site

Answer 31

irreversible enzyme inhibitor

Question 32

inhibitors do not have structures similar to that of enzyme’s normal substrate

Answer 32

irreversible inhibition

Question 33

It is often regulated by the cell. Often the reason for this is to conserve energy because if the cell runs out of chemical energy, it will die; therefore many mechanism exist to converse energy.

Answer 33

regulation of the enzyme activity

Question 34

Enzymes that have more than one a single site. It has an active sites that can be altered by binding of a small molecules called effector molecules or regulators.

Answer 34

allosteric enzymes

Question 35

inhibit enzyme action

Answer 35

negative allosterism

Question 36

stimulate enzyme action

Answer 36

positive allosterism

Question 37

The production of the enzyme in an active form.

Answer 37

proenzyme

Question 38

This is a process in which a chemical group is covalently added to or removed from the protein.

Answer 38

protein modification

Question 39

It is an enzyme regulation process in which formation of a product inhibits an earlier reaction in the sequence.

Answer 39

feedback control

Question 40

refers to the enzymes that are used directly or as components of the assay system for the determination of number of substances

Answer 40

diagnostic enzymes

Question 41

is the component that is neither a blood cell (serum does not contain white or red blood cells) nor a clotting factor; it is the blood plasma with the fibrinogens removed.

Answer 41

serum

Question 42

➜ Important enzyme found throughout the body and involved in glucose metabolism ➜ The analysis of isoenzyme patterns can help in the investigation of myocardial infarction. ➜ Tetramer of 2 different subunits(H or M)

Answer 42

lactate dehydrogenase

Question 43

is found predominantly in heart muscle, kidney and in RBCs

Answer 43

LDH1 and LDH2

Question 44

is found in a variety of tissues such as spleen, lung, endocrine glands and lymph nodes

Answer 44

LDH3

Question 45

found in liver, skin and skeletal muscle is the least stable and runs the shortest on electrophoresis

Answer 45

LDH4 and LDH5

Question 46

o Formally known as glutamate pyruvate transaminase (GPT) o Found in high concentrations in liver cells and in much smaller concentrations elsewhere.

Answer 46

alanine transaminase

Question 47

➜ High levels are found in liver, bone, placenta and intestine ➜ Used as a marker of cholestatic liver disease ➜ Separation by electrophoresis and also assessed using inhibitors, specific substrates or by heat inactivation of other isoenzymes.

Answer 47

alkaline phosphatase

Question 48

➜ Also known as creatine phosphatase (CPK) ➜ Mainly found in heart and skeletal muscle and in brain

Answer 48

creatine kinase

Question 49

➜ Maximum activity-pH-5-6 ➜ Found in large amounts in prostate glands and its assay in plasma has been used in the diagnosis of prostatic carcinoma

Answer 49

acid phosphatase

Question 50

➜ The enzyme catalyze the hydrolysis of choline esters ➜ Presence is assumed when the muscle relaxant scoline is administered.

Answer 50

cholinesterase

Question 51

Found in biliary ducts of the liver, in the kidney and pancreas with the largest amounts being in kidney

Answer 51

a-glutamyltrasferase (ggt,agt)

Question 52

Found in high concentrations in pancreas and salivary glands where it is secreted to digest complex carbohydrates

Answer 52

amylase

Question 53

are unbranched polymers composed of repeating patterns called nucleotides

Answer 53

nucleic acids

Question 54

- stores genetic information of an organism - has million nucleotides - is contained in the chromosomes of nucleus, each chromosome having a different type

Answer 54

DNA

Question 55

- translates this genetic information into synthesis of proteins - has thousand nucleotides

Answer 55

RNA

Question 56

human chromosomes

Answer 56

46 (23 pairs)

Question 57

is a portion of the DNA molecule responsible for the synthesis of a single protein

Answer 57

gene

Question 58

- A monosaccharide + a base + phosphate - is formed by joining the anomeric carbon of the monosaccharide with a nitrogen- atom of the base.

Answer 58

nucleotide

Question 59

3 parts of nucleotide

Answer 59

a) Nitrogen-containing base b) Sugar (monosaccharide) c) Phosphate group

Question 60

nitrogen atom at the 1 position bonds with the 1’ carbon of sugar

Answer 60

pyrimidine bases

Question 61

nitrogen atom at the 9 position bonds with the 1’ carbon of the sugar

Answer 61

purine bases

Question 62

• DNA Abbreviation: A Nucleotide: Deoxyadenosine 5’-monophosphate Abbreviation: dAMP • RNA Nucleotide: Adenosine 5’-monophosphate Abbreviation: AMP

Answer 62

adenine

Question 63

• DNA Abbreviation: G Nucleotide: Deoxyguanosine 5’- monophosphate Abbreviation: dGMP • RNA Nucleotide: Guanosine 5’-monophosphate Abbreviation: GMP

Answer 63

guanine

Question 64

• DNA Abbreviation: C Nucleotide: Deoxycytidine 5’-monophosphate Abbreviation: dCMP • RNA Nucleotide: Cytidine 5’-monophosphate Abbreviation: CMP

Answer 64

cytosine

Question 65

• DNA Abbreviation: T Nucleotide: Deoxythymidine 5’-monophosphate Abbreviation: dTMP

Answer 65

thymine

Question 66

• RNA Abbreviation: U Nucleotide: Uridine 5’-monophosphate Abbreviation: UMP

Answer 66

uracil

Question 67

- The combination of sugar + Base - monosaccharide + base

Answer 67

nucleoside

Question 68

difference of DNA and RNA

Answer 68

o DNA contains the sugar deoxyribose, while RNA contains the sugar ribose. o DNA is a double-stranded molecule while RNA is a single stranded molecule. • DNA is stable under alkaline conditions while RNA is not stable.

Question 69

first to describe the three- dimensional structure of DNA in 1953

Answer 69

James Watson and Francis Crick

Question 70

describes the manner in which the nitrogenous bases of the DNA molecules align with each other

Answer 70

Complementary base pairing

Question 71

The DNA molecule is composed of two strands held together by hydrogen bonds. A single strand is different at its two ends. One end is called 5' (5 prime), the other is called 3' (3 prime).

Answer 71

antiparallel strands

Question 72

are piece of DNA that carry the genetic instructions, or genes of an eukaryote or prokaryote organism

Answer 72

chromosomes

Question 73

are organism with a simple cellular structure in which there is no sure nucleus surrounded by a nuclear membrane and there are no true membrane bound organelles

Answer 73

prokaryotes

Question 74

are organism that have cells containing a true nucleus enclosed by a nuclear membrane

Answer 74

eukaryotes

Question 75

- The flow of information from DNA to RNA to protein is termed as the _____ of molecular biology. (except with viruses)

Answer 75

“central dogma”

Question 76

is the process by which DNA makes a copy of itself when a cell divides

Answer 76

replication

Question 77

is the ordered synthesis of RNA from DNA. In this process, the genetic information stored in DNA is passed into RNA.

Answer 77

transcription

Question 78

is the synthesis of proteins from RNA. In this process, the genetic message contained in RNA determines the specific amino acid sequence of a protein.

Answer 78

translation

Question 79

unwinds and separates double stranded DNA as it moves along the DNA

Answer 79

DNA helicase

Question 80

a type of RNA polymerase that generates RNA primers

Answer 80

DNA primase

Question 81

synthesize new DNA molecules by adding nucleotides to leading and lagging DNA strands

Answer 81

DNA polymerases

Question 82

unwinds and rewinds DNA strands to prevent the DNA from becoming tangled or supercoiled

Answer 82

Topoisomerase or DNA Gyrase

Question 83

group of enzymes that remove nucleotide bases from the end of a DNA chain

Answer 83

exonucleases

Question 84

joins DNA fragments together by forming phosphodiester bonds between nucleotides

Answer 84

DNA ligase

Question 85

From Latin word transcribe and simply means “to make a copy”. Thus, in this process, part of the information in the DNA is copied into a strand of RNA.

Answer 85

RNA transcription

Question 86

- carries the genetic information for protein from DNA to the ribosomes. It is a complimentary RNA copy of a gene on the DNA - 750 nucleotides

Answer 86

Messenger RNA (mRNA)

Question 87

Is a structural and functional component of the ribosomes, which are “platforms” on which protein synthesis occurs

Answer 87

Ribosomal RNA (rRNA)

Question 88

- translate the genetic code of the mRNA into the primary sequence of amino acids in the protein. - Contain 73-93 nucleotides per chain.

Answer 88

Transfer RNA (tRNA)

Question 89

are enzymes that transcribe DNA into RNA. Using a DNA template, RNA polymerase builds a new RNA molecule through base pairing.

Answer 89

RNA polymerase

Question 90

• It involves translating the genetic information from the sequence of nucleotides into the sequence of amino acids in the primary structure of protein. • Protein

Answer 90

RNA translation

Question 91

is the change in sequence of nucleotide of DNA

Answer 91

mutation

Question 92

It occurs as a result of replacement of one nucleotide by other in specific nucleotide sequence of gene

Answer 92

point mutation

Question 93

• It is also known as neutral mutation. • It is the mutation in which mutated codon codes same amino acids as the original codon.

Answer 93

silent mutation

Question 94

In this mutation mutated codon codes different amino acid (other than original)

Answer 94

missense mutation

Question 95

Mutation in which altered codon is stop codon or chain terminating codon, such mutation is called non-sense mutation

Answer 95

nonsense mutation

Question 96

It occurs as a result of addition or deletion of nucleotide in the sequence of DNA

Answer 96

frameshift mutation

Question 97

any chemical that cause a change in the DNA sequence

Answer 97

mutagens

Question 98

is caused by mutations in genes that are involved in repairing damaged DNA

Answer 98

xeoderma pigmentosum

Question 99

is a piece of DNA having its own replication origin so that it can be replicated inside a host cell.

Answer 99

DNA cloning vector

Question 100

using recombinant DNA technology to modify an organism’s DNA to achieve desirable traits.

Answer 100

genetic engineering