Biology Molecular Genetics

Question 1

The transmission of information through DNA, RNA, and proteins is called the ___ dogma of molecular biology

Answer 1

central

Question 2

___ is the basis for heredity

Answer 2

DNA

Question 3

DNA is ___ and can be altered under certain conditions

Answer 3

mutable

Question 4

DNA is transcribed (__) into RNA which is then translated (translation) into proteins

Answer 4

transcription

Question 5

CUT the PYe: C, U, and __ are pyrimidines

Answer 5

Thymine

Question 6

PURe As ___

Answer 6

Gold

Question 7

Pyrimidines have one ring in their ___

Answer 7

structure

Question 8

Purines have two rings in their ___

Answer 8

structure

Question 9

___: basic unit of DNA

Answer 9

nucleotide

Question 10

___ uses Uracil instead of Thymine

Answer 10

RNA

Question 11

If the 5’ carbon is at the end of the DNA strand, then that end is referred to as the 5’ ___

Answer 11

end

Question 12

DNA is most commonly found in nature as a double-stranded helices of complementary strands with the sugar-phosphate chains on the outside of the helix and the nitrogenous basis on the ___

Answer 12

inside

Question 13

The strands of DNA are held together by hydrogen bonds between the bases oriented toward the ___

Answer 13

center

Question 14

Adenine forms two hydrogen bonds with ___

Answer 14

Thymine

Question 15

Guanine forms three hydrogen bonds with ___

Answer 15

Cytosine

Question 16

DNA replication involves the breaking of hydrogen bonds between nitrogenous bases from each ___

Answer 16

strand

Question 17

The opening of the DNA molecule created by DNA helicase is known as the ___ fork

Answer 17

replication

Question 18

As DNA is replicated, the replication fork continues to travel up the DNA molecule which could cause a buildup of ___ strain (due to twisting of the DNA molecule) upstream of the replication fork

Answer 18

torsional

Question 19

___ removes torsional strain involved in DNA replication by cutting, twisting, and then rejoining the strands of DNA

Answer 19

Topoisomerase

Question 20

The area that takes place after the replication fork has passed a portion of DNA is known as the ___bubble

Answer 20

replication

Question 21

Each single strand of DNA can act as a template for complementary base pairing and allows for the ___ of two new daughter strands

Answer 21

synthesis

Question 22

Each new daughter helix contains an intact strand from the parent helix and a newly ___ strand; this type of replication is called semiconservative

Answer 22

synthesized

Question 23

The daughter strands of DNA formed from the parent strands are ___ to the parent strands

Answer 23

identical

Question 24

Creation of daughter strands is the result of DNA ___

Answer 24

polymerase

Question 25

With the exception of DNA polymerase’s reading direction (a few untested ___), everything in molecular biology is 5’ to 3’

Answer 25

endonucleases

Question 26

DNA polymerase reads 3’ to 5’, but the following processes occur 5’ to 3’: DNA syntheses, DNA repair, RNA ___, RNA translation (reading of codons)

Answer 26

transcription

Question 27

DNA polymerase can only add nucleotides to 3’ ends of DNA ___

Answer 27

strands

Question 28

The leading strand has its 3’ end facing towards the replication fork, thereby allowing DNA polymerase/DNA synthesis and the replication fork to travel in the same ___

Answer 28

direction

Question 29

Since the leading strand has its 3’ end facing toward the replication fork the result is the leading ___being continually synthesized

Answer 29

strand

Question 30

The lagging strand has its 3’ end facing away from the replication ___

Answer 30

fork

Question 31

In order to replicate the entire lagging strand, additional DNA polymerase proteins must reattach to the parent strand near the continually moving ___ fork

Answer 31

replication

Question 32

___ fragments: Discontinuous synthesis results in short fragments of synthesized DNA

Answer 32

Okazaki

Question 33

During DNA polymerase’s sequence, these ___ are joined together by DNA ligase

Answer 33

fragments

Question 34

Transcription is the process in which ___ information is passed from DNA to RNA

Answer 34

genetic

Question 35

Messenger RNA, is transcribed in 5’ to 3’ direction and is complementary and ___ to the DNA template strand

Answer 35

antiparallel

Question 36

The coding __ of DNA is identical to the mRNA strand (with the exception that all thymine bases are exchanged for uracil)

Answer 36

strand

Question 37

___ is the process in which genetic information is passed from mRNA to protein

Answer 37

translation

Question 38

The ribosome translates the mRNA in the 5’ to 3’ direction and the protein is synthesized from the amino terminus (N-terminus) to the ___ terminus (C-terminus)

Answer 38

carboxyl

Question 39

For RNA, the ___ constituent is ribose (instead of deoxyribose)

Answer 39

sugar

Question 40

Most RNA is ___ stranded

Answer 40

single

Question 41

RNA can be found in both the ___ and the cytoplasm of the cell

Answer 41

nucleus

Question 42

Three major types of RNA include: mRNA, tRNA and ___

Answer 42

rRNA

Question 43

___ RNA carries the complement of a DNA sequence. It then transports this information from the nucleus to the ribosomes for protein synthesis

Answer 43

Messenger

Question 44

mRNA is made from ___ complementary to the template strand of DNA

Answer 44

ribonucleotides

Question 45

Eukaryotic mRNA is ___, meaning that one mRNA strand codes for one polypeptide

Answer 45

monocistronic

Question 46

___ RNA is a small RNA molecule found in the cytoplasm

Answer 46

tRNA

Question 47

tRNA assists in the translation of mRNA’s ___ code into a sequence of amino acids coded for in the mRNA sequence to the ribosomes during protein synthesis

Answer 47

nucleotide

Question 48

tRNA recognizes both the mRNA ___ and its corresponding amino acid

Answer 48

codon

Question 49

tRNA has a dual ___ and this is reflected in its three dimensional structure

Answer 49

function

Question 50

One end of tRNA contains a three-nucleotide sequence, the ___, which is complementary to one of the mRNA codons

Answer 50

anticodon

Question 51

rRNA (ribosomal RNA) is synthesized in the nucleolus of eukaryotes and in the ___ of prokaryotes

Answer 51

cytoplasm

Question 52

Transcription is the process through which information coded in the sequence of DNA is used to direct the ___ of a strand of RNA

Answer 52

synthesis

Question 53

After ___ modification, the RNA leaves the nucleus through nuclear pores

Answer 53

post-transcriptional

Question 54

The first step of transcription occurs when RNA polymerase binds to the DNA ___ strand at a promoter region, a short DNA sequence found upstream from the site where transcription of a specific RNA is going to take place

Answer 54

template

Question 55

In a process very similar to DNA replication, the RNA polymerase surrounds the DNA molecule after it has been opened by the actions of DNA ___ and topoisomerase

Answer 55

helicase

Question 56

Once RNA polymerase has bound to the template DNA strand, it recruits and adds complementary RNA ___, thereby transcribing a new RNA strand

Answer 56

nucleotides

Question 57

RNA that has not yet been processed is known as hetero-nuclear RNA (hnRNA), or pre-RNA and contains extra nucleotides that are not ___ to create the corresponding protein

Answer 57

necessary

Question 58

Extra sequences on hnRNA are called ___ and are subsequently spliced out (removed) by the spliceosome

Answer 58

introns

Question 59

___ are the nucleotides necessary to make the protein and are kept during the post-transcriptional processing

Answer 59

exons

Question 60

The function of the terminal structures RNA receives before leaving the nucleus is to provide protection from RNA-degrading ___ within the cytosol

Answer 60

enzymes

Question 61

Once these three modifications are made to the RNA molecule, it is termed messenger RNA (mRNA) and can ___ the nucleus

Answer 61

leave

Question 62

Stop codons are UAA, UGA and ___

Answer 62

UAG

Question 63

The redundancy in amino acid sequence codons accomodates a ___ position which is a third nucleotide in a given sequence having a corresponding amino acid in common with other sequences

Answer 63

wobble

Question 64

___ is the process through which mRNA codons are translated into a sequence of amino acids

Answer 64

translation

Question 65

translation occurs in the ___

Answer 65

cytoplasm

Question 66

initiation begins when the small ribosomal subunit binds to the ___ near its 5’ end

Answer 66

mRNA

Question 67

Initiation occurs when the ribosome scans the mRNA until it binds to a start ___, which codes for methionine

Answer 67

codon

Question 68

Once the mRNA, small ribosomal subunit, and the aminoacyl-tRNA complex is bound, the large ribosomal subunit binds, forming the ___ initiation complex

Answer 68

completed

Question 69

Elongation is a ___ step cycle that is repeated for each amino acid added to the protein after the initiator methionine

Answer 69

three

Question 70

During elongation, the ribosome moves in the 5’ to 3’ direction along the mRNA, synthesizing the protein from its amino (N-) to ___ (C-) terminus

Answer 70

carboxyl

Question 71

The ___ contains three important binding sites

Answer 71

ribosome

Question 72

The A site holds the incoming aminoacyl-tRNA complex, which will be the next amino acid added to the ___ chain

Answer 72

growing

Question 73

The incoming aminoacyl-tRNA complex is determined by ___ codons

Answer 73

mRNA

Question 74

The P site holds the tRNA that carries the growing polypeptide chain where the initiation ___ formed (methionine)

Answer 74

complex

Question 75

A ___ bond is formed as the polypeptide is passed from the tRNA in the P site to the tRNA in the A site

Answer 75

peptide

Question 76

On the P site, the peptide bond requires ___ and is completed by the ribosome

Answer 76

energy

Question 77

The E site is where the now uncharged tRNA briefly pauses before it is expelled from the ___, to be recharged

Answer 77

ribosome

Question 78

Elongation is completed by translocation, in which the ribosome advances three ___ along the mRNA in the 5’ to 3’ direction

Answer 78

nucleotides

Question 79

When the ribosome advances during translocation, the tRNA’s ___ on the ribosome shifts

Answer 79

position

Question 80

During ___, the charged tRNA (bound to the polypeptide) is transferred from the A site to the P site

Answer 80

translocation

Question 81

During translocation, the uncharged ___ is transferred from the P site to the E site, where it is expelled

Answer 81

tRNA

Question 82

After translocation, the result is an ___ A site ready for the entry of the aminoacyl-tRNA corresponding to the next codon

Answer 82

empty

Question 83

When a stop codon is reached, ___ is triggered

Answer 83

termination

Question 84

Modification of a newly translated polypeptide chain can include ___, where certain amino acid sequences are removed from the chin, or addition, where biomolecules are added to the peptide

Answer 84

cleavage

Question 85

___: addition of a phosphate group

Answer 85

phosphorylation

Question 86

___: addition of a carboxylic acid groups

Answer 86

carboxylation

Question 87

___: addition of oligosaccharides (sugars), completed in the Golgi body

Answer 87

glycosylation

Question 88

___: addition of lipid groups, allowing for incorporation of the protein into membranes

Answer 88

prenylation

Question 89

In eukaryotes, transcription occurs in the nucleus while in prokaryotes, this occurs in the ___(due to a lack of membrane-bound organelles)

Answer 89

cytoplasm

Question 90

Since prokaryotes do not have a ___, posttranscriptional modification does not occur

Answer 90

nucleus

Question 91

prokaryotes have polycistronic mRNA transcripts while eukaryotes have ___ mRNA transcripts

Answer 91

monocistronic

Question 92

Monocistronic means one transcript ___ to one protein

Answer 92

translates

Question 93

polycistronic means one transcript translates to multiple ___, often due to multiple start codons

Answer 93

proteins

Question 94

In addition, due to the lack of membrane-bound organelles in prokeryotes, transcrption and translation can occur at the same ___ in the cell. This results in transcrption and translation occuring concurrently in prokaryotes

Answer 94

location

Question 95

The primary structure (1 degree) of a protein is the sequence of amino acids determined by its ___ strand

Answer 95

mRNA

Question 96

Primary structure lists amino acids from the ___ to the C-terminus

Answer 96

N-terminus

Question 97

Peptide bonds are central to a protein’s ___ structure

Answer 97

primary

Question 98

The local 3D structure of neighboring amino acids of a protein which is determined by the primary structure is the ___ structure

Answer 98

secondary

Question 99

The most common secondary structures are alpha-helices and ___-sheets

Answer 99

beta

Question 100

Secondary structure stability relies on ___ bond formation between amino acid side chains

Answer 100

hydrogen

Question 101

The ___ structure of a protein refers to the folding of a polypeptide forming the 3D structure of the entire protein itself

Answer 101

tertiary

Question 102

The folding which occurs in a tertiary structure of a protein is often assisted by chaperones, cellular proteins that stabilize transition states in the ___ process

Answer 102

folding

Question 103

Tertiary structure relies on the ___ and hydrophilic interactions of amino acid side groups as well as disulfide bonds

Answer 103

hydrophobic

Question 104

The ___ structure of a protein describes the combining of polypeptides to form a complete ___ complex

Answer 104

protein

Question 105

Quaternary structure relies on both hydrophobic and hydrophilic interactions as well as ___ bonds

Answer 105

disulfide

Question 106

Not all proteins have ___ structure

Answer 106

quaternary

Question 107

Two major types of proteins are non-enzymatic and ___

Answer 107

enzymatic

Question 108

Non-enzymatic functions are wide-reaching but generally fall into two major categories: structural and ___

Answer 108

binding

Question 109

Structural proteins, including cytoskeleton components and motor proteins, have the primary functions to fix cellular components in place or to move ___ components to their needed location

Answer 109

cellular

Question 110

Binding proteins serve to transport, attach, or sequester molecules by directly ___ to the molecule

Answer 110

adhering

Question 111

A catalyst is any substance that affects the rate of a chemical reaction while remaining ___ or being regenerated as a product

Answer 111

unchanged

Question 112

Typically, catalysts, and therefore enzymes, increase the reaction rate through reduction of the activation ___ of the reaction

Answer 112

energy

Question 113

Conjugated protein covalently bond to other groups (lipids, sugars, cations, etc.) that often serve as ___ or cofactors

Answer 113

coenzymes

Question 114

The molecule the enzyme acts on is called the ___

Answer 114

substrate

Question 115

There is an area on each enzyme to which the substrate binds, called the ___ site

Answer 115

active

Question 116

Most ___ reactions are reversible

Answer 116

enzyme-catalyzed

Question 117

The product synthesized by an enzyme can be decomposed by the ___ enzyme

Answer 117

same

Question 118

Enzymes do NOT ___ the equilibrium constant

Answer 118

alter

Question 119

Enzymes are NOT ___ in the reaction

Answer 119

consumed

Question 120

Enzymes will appear in both the ___ and the products of a given reaction

Answer 120

reactants

Question 121

Enzymes lower the activation energy of a ___, thereby speeding up the reaction

Answer 121

reaction

Question 122

Enzymes are pH-and temperature-sensitive, with optimal activity at specific pH ___ and temperatures

Answer 122

ranges

Question 123

The Lock and Key Theory holds that the spatial structure of an enzyme’s active site is exactly ___ to the spatial structure of its substrate

Answer 123

complementary

Question 124

When the appropriate substrate comes in contact with the active site, the conformation of the active site ___ to fit the substrate (Induced Fit Theory)

Answer 124

changes

Question 125

Enzyme action and the reaction rate depend on several environmental factors including ___, pH, and the concentration of enzyme and substrate

Answer 125

temperature

Question 126

Beyond optimal temperature, heat alters the shape of the active site of the enzyme molecule and deactivates it, ___ to a rapid drop in rate of action

Answer 126

leading

Question 127

Vmax is the reaction rate as substrate ___ goes to infinity

Answer 127

concentration

Question 128

In order to change Vmax, more ___ must be added

Answer 128

enzyme

Question 129

Km represents the substrate concentration needed to fill half of the enzyme’s ___ sites

Answer 129

active

Question 130

Km can be used to assess an enzyme’s ___ for a substrate

Answer 130

affinity

Question 131

A higher Km requires a higher ___ of substrate to reach 1/2Vmax

Answer 131

concentration

Question 132

Affinity and Km are ___ related

Answer 132

inversely

Question 133

If sufficient quantities of the substrate are introduced (competitive inhibition), however, the substrate can outcompete the competitor and will still be able to reach the Vmax; however, this will require much higher concentrations of ___ than would be necessary without the competitor

Answer 133

substrate

Question 134

A noncompetitive inhibitor is a substance that binds to an ___ at a site other than the active site

Answer 134

enzyme

Question 135

The interaction of the noncompetitive inhibitor at an ___ site (allosteric means “other site” or “other structure”) changes the structure of the enzyme, resulting in a nonfunctional active site

Answer 135

enzyme

Question 136

Noncompetitive inhibition is considered to be a type of ___ inhibition

Answer 136

allosteric

Question 137

___ catalyze addition or synthesis reactions, generally between large, similar molecules, and often require ATP

Answer 137

Ligases

Question 138

___ catalyze the rearrangement of bonds within a molecule

Answer 138

Isomerases

Question 139

Some isomerases can also be classified as oxidoreductases, transferases, or lyases, depending on the ___ of the enzyme

Answer 139

mechanism

Question 140

Isomerases ___ reactions between stereoisomers as well as constitutional isomers

Answer 140

catalyze

Question 141

___ catalyze the cleavage of a single molecule into two products

Answer 141

Lyases

Question 142

Lyases do not require ___ as a substrate and do not act as oxidoreductases

Answer 142

water

Question 143

When a Lyase catalyzes the synthesis of two small molecules into a single molecule, it is common for them to be ___ to as synthases

Answer 143

referred

Question 144

___ catalyze the breaking of a compound into two molecules using the addition of water

Answer 144

Hydrolases

Question 145

LIL’HOT

Answer 145

Ligase, Isomerase, Lyase, Hydrolase,Oxidoreductase, Transferase

Question 146

___ catalyze oxidation-reduction reactions, that is, the transfer of electrons between ___ molecules

Answer 146

Oxidoreductases

Question 147

In reactions catalyzed by oxidoreductases, the electron donor is known as the ___, and the electron acceptor is known as the oxidant

Answer 147

reductant

Question 148

___ catalyze the movement of a functional group from one molecule to another

Answer 148

Transferases

Question 149

Kinases are also a member of the ___ class

Answer 149

Transferase

Question 150

___ catalyze the transfer of a phosphate group, generally from ATP to another molecule

Answer 150

Kinase