Molecular Biology Test 1

Front 1

Adenine

Back 1

Derivative of Purine. One of 4 basic building blocks of DNA. Binds to Thymine

Front 2

Antiparallel

Back 2

DNA is antiparallel, strands run in different directions. 5' - 3' and 3'-5'

Front 3

Central Dogma

Back 3

The idea that genetic information flows from DNA -> DNA , DNA -> RNA, and RNA -> Protein

(Replication, Transcription, Translation)

Front 4

Chargaff's Rules

Back 4

1. A=T, G=C
2. Same in both strands

Front 5

cytosine 

Back 5

Derivative of Pyrimidine, One of 4 basic building blocks of DNA. Binds to Guanine

Front 6

deoxyribonucleic acid (DNA)

Back 6

Anti parallel Double-helix, made of ATGC, Contains code for all genetic info.

Front 7

DNA replication 

Back 7

Genetic info flowing from DNA->DNA. Creates identical DNA strand copy.

Front 8

genotype

Back 8

The genetic makeup of an organism. Determines its physical trait.

Front 9

guanine

Back 9

Derivative of Purine. One of 4 basic building blocks of DNA. Binds to Cytosine

Front 10

messenger RNA (mRNA)

Back 10

Major component of translation. Takes genetic code to ribosome for amino acid production

Front 11

nucleic acid

Back 11

linear chains of nucleotides

Front 12

nucleoside 

Back 12

formed from Pyrimidine bases and Purine bases bond with Deoxyribose sugar

Front 13

nucleotide 

Back 13

Formed by adding a phosphate to a nucleoside. Building block of nucleic acid.

Front 14

phenotype 

Back 14

An organism's physical traits.

Front 15

purine 

Back 15

Base compound for Adenine and Guanine

Front 16

pyrimidine 

Back 16

Base compound for Thymine and Cytosine

Front 17

ribosome 

Back 17

Protein sythetic factory. form Amino acids/ polypeptides

Front 18

ribonucleic acid (RNA) 

Back 18

Single strand of genetic info. Made of AUGC. U = Uracil

Front 19

thymine 

Back 19

Derived from pyrimidine. building block of DNA. Binds with Adenine

Front 20

transcription 

Back 20

going from DNA ->RNA

Front 21

transfer RNA (tRNA) 

Back 21

Carries amino acids to ribosomes to create polypeptide chains

Front 22

Avery, MacLeod, McCarty,

Back 22

proved "biological specificity" of Nucleic acids. continued work of Griffith

Front 23

translation 

Back 23

RNA - > Amino Acid (Polypeptide)

Front 24

uracil 

Back 24

Derivative of pyrimidine, replaces Thymine in RNA.

Front 25

Mendel

Back 25

3 laws of inheritance

1. Independent assortment = Traits inherited separately of each other
2. Independent Segregation - genes can be different or same. 1 allele from each parent
3. Dominance = 1 allele dominant, 1 allele recessive. 3:1 ration. (Dominant = tall, recessive = short, 3 tall 1 short)

Front 26

Miescher

Back 26

First discovered DNA, called it Nuclein.

Front 27

Garrod, Beadle, Tatum

Back 27

Garrod first showed Genotype determines Phenotype.

Beadle, Tatum proved this theory, also hypothesized 1 gene, 1 polypeptide.

Front 28

 Levene

Back 28

Discovered 4 bases of DNA, ATGC

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Todd

Back 29

proved 3' to 5' directionality and terminus'

Front 30

Griffith

Back 30

first hint at DNA being genetic material, with mice and R&S colonies

Front 31

Chargaff,

Back 31

Chargaffs rules, 1. A=T, G=C

Front 32

Hershey, Chase

Back 32

Proved that phages transfered DNA.

Front 33

Franklin, Wilkins

Back 33

Discovered A-DNA and B-DNA by using x-ray crystallography. Lead to discovery of DNA structure.

Front 34

Watson, Crick

Back 34

proposed DNA as double stranded helix.

Front 35

affinity chromatography 

Back 35

exploits a proteins ability to bind ligands. attaches ligands to beads, pours bacteria through, some proteins bind to the ligands, helps determine which proteins are present.

Front 36

α‐helix 

Back 36

2' structure of polypeptide. H-bonds on inside give structure and regularity.

Front 37

amino acid 

Back 37

basic building block of polypeptides.

Front 38

β‐strand 

Back 38

makes up β‐sheet. fully extended region of peptide chain

Front 39

β‐turn 

Back 39

Connects α-helix and β‐strand. allows polypeptide to change to direction. gives super secondary structure

Front 40

β‐sheet (antiparallel, parallel) 

Back 40

Multiple β‐strands make up sheet.

Antiparallel = sheets run opposite direction

Parallel = sheets run same direction.

Front 41

column chromatography 

Back 41

separates proteins by repeatedly partitioning through columns of beads Then analyzes with a UV monitor.

Front 42

denatured state 

Back 42

protein is denatured after excessive heat or chemical agents. Weak non-covalent bonds are broken. made up of random conformations.

Front 43

disulfide bond 

Back 43

Disulfide bonds are created during the synthesis of cystine. Aids in tertiary structure.

Front 44

electrophoresis 

Back 44

protein sample applied to one end of gel plate, electrode to the other end. Pulls certain proteins further down field based on their isoelectric pH.

Front 45

gel filtration 

Back 45

Separates proteins by size. Uses special beads that capture smaller proteins, and let large pass by.

Front 46

hydrogen bond 

Back 46

non-covalent. only between NOF and H. H bonds between AT and GC help stabilize DNA. 2' and 3' structures as well.

Front 47

hydrophobic interactions 

Back 47

Water molecules surround hydrophobic amino acids. Seen in 3' 4' protein structures

Front 48

hydrophobicity 

Back 48

tendency of molecules to aggregate in water.

Front 49

ion‐exchange chromatography 

Back 49

Uses electrostaic interactions to separate proteins. Charged beads attract certain proteins.

Front 50

ionic bond 

Back 50

Stabilize 3' structure. can be disrupted by pH

Front 51

molecular chaperone 

Back 51

attach to hydrophobic regions of polypeptides. can help fold polypeptide chains.

Front 52

molecular exclusion chromatography 

Back 52

same as gel filtration

Front 53

peptide 

Back 53

Amino acids bonded together create a peptide

Front 54

peptide bonds 

Back 54

Amide bond that links amino acids, forms peptides or polypeptides.

Front 55

peptidylprolyl cis‐trans isomerase 

Back 55

changes cis and trans peptide bonds. accelerates protein folding

Front 56

tertiary structure 

Back 56

3d structure. contains multiple super secondary structures. can be a protein

Front 57

polypeptide 

Back 57

long chain of >1 amino acids

Front 58

primary structure 

Back 58

1 linear chain of amino acids. (Polypeptide)

Front 59

protein 

Back 59

3' or 4' structure. made of different regions and sometimes >1 pp chain

Front 60

protein disulfide isomerase 

Back 60

PDI corrects sulfide bonds in proteins. Enzyme. process not known.

Front 61

quaternary structure 

Back 61

>1 pp chain makes up a protein. not all proteins are 4'

Front 62

residue 

Back 62

Amino acids once linked together by peptide bonds are called residues

Front 63

secondary structure 

Back 63

has folding patterns ( a-helix, b-sheets) in single pp chain

Front 64

van der Waals interactions 

Back 64

assist in folding. polar and non polars react. can attract and repel.

Front 65

substrate 

Back 65

molecule that en enzyme is catalyzing

Front 66

hypervariable region 

Back 66

small region in IgG. Important contributor to antigen binding specificity.

Front 67

Bohr effect 

Back 67

Decrease in pH or increase in Co2 causes hemoglobin to release oxygen.

Front 68

immunoglobulin G (IgG) 

Back 68

4' protein. In immune system. has 12 domains. and 4 pp chains. 2 light 2 heavy.

Front 69

cooperativity 

Back 69

communication between the 4 heme groups that allows hemoglobin to gain and lose oxygen.

Front 70

induced fit mechanism 

Back 70

Enzyme changes shape to fit substrate

Front 71

domain 

Back 71

region in large pp chain. often has certain function. Fold might occur.

Front 72

light chain 

Back 72

short pp chain of a 4' structure protein

Front 73

energy of activation 

Back 73

energy needed to start/complete enzyme reaction

Front 74

lock and key mechanism 

Back 74

active site fits perfectly to substrate

Front 75

allosteric site, allosteric effectors 

Back 75

Allosteric effector = small molecule that binds to a protein and cause a change in its function.

Allosteric site = binding to sites other than active sites.

Front 76

enzyme 

Back 76

catalyst that speeds up metabolic processes

Front 77

myoglobin 

Back 77

3' structure = oxygen storage system in muscle. Single heme group stores oxygen.

Front 78

enzyme‐substrate complex 

Back 78

Molecule while Enzyme and substrate are bonded, during reaction.

Front 79

sickle cell anemia 

Back 79

-Causes Hemoglobin to fail at binding oxygen.
- Difference in regular cell and sickle cell is a single Amino acid change.

Malaria is resistant to sickled cells.

Front 80

heavy chain 

Back 80

Long pp chain. part of 4' structure protein.

Front 81

variable region 

Back 81

in IgG, where antigens bind

Front 82

hemoglobin 

Back 82

Hemoglobin - 4' = oxygen transport system in blood. 4 subunits = 4 heme groups

Front 83

quaternary structure 

Back 83

>1 pp chain making up a protein. can have domains. not required.

Front 84

A‐DNA 

Back 84

Right handed helix, discovered by franklin, very rare

Front 85

palindrome 

Back 85

(dyad symmetry) aka inverted repeats = reads the same forwards and backwards
In DNA

Front 86

B‐DNA 

Back 86

Most common. Right handed DNA, Watson and crick

Front 87

plasmid 

Back 87

Small, circular, self replicating DNA molecule

Front 88

base‐stacking 

Back 88

Stabilizes DNA structure.

Front 89

DNA gyrase 

Back 89

Introduces negative supercoils to counteract positive supercoiling that helicase may create. in bacteria.

Front 90

stem‐loop structure 

Back 90

(Hairpin) Spacer in palindrome cause the loop. Bases aren't complimentary in loop, cant bind to each other.

Front 91

renaturation 

Back 91

Re-annealing, complimentary single strands come together.

Front 92

cruciform structure 

Back 92

caused by inverted repeats, H bonds between bases of same strands

Front 93

single‐strand DNA binding protein (SSB) 

Back 93

Bind to single stranded DNA after helicase seperates and prevents strands from re-annealing

Front 94

supercoil 

Back 94

when double helix is wound around itself. This changes the conformation. ( Topology)

Front 95

helicase 

Back 95

Enzyme that separates the strands of the DNA double helix.

4' structure, homohexamer, one strand goes through middle.

Requires energy!

Front 96

topoisomer 

Back 96

otherwise identical DNA molecules with different degrees of supercoiling.

Front 97

topoisomerase (Type I, Type II) 

Back 97

- these enzymes introduce a brief or tansient cleavage of the DNA backone, PDE. 3' structure.

- type I = transient single stranded dna breaks. no ATP required.

- type II =transient double stranded dna breaks. Requires ATP

Front 98

melting temperature 

Back 98

-Tm= melting temp, point at which the DNA strands are 1/2 seperated,(1/2 denatured)

Front 99

nicked circular DNA 

Back 99

Phosphodiester backbone has "nick" or missing piece in it. Cannot supercoil.

Front 100

interphase 

Back 100

Phase of cell's life where DNA RNA and Proteins are synthesized. ~90% of its life is spent in this phase

Front 101

metaphase 

Back 101

Spindles attached to kinetochores of chromatids. Chromatids move towards middle of cell

Front 102

beads on a string 

Back 102

DNA winds around a 8 histone complex like beads on a string to produce a nucleosome. DNA between histones is known as linker DNA

Front 103

nucleoid 

Back 103

Super condensed complex of proteins and DNA in Bacteria

Front 104

euchromatin 

Back 104

Less condensed form of chromatin in Eukaryotic cell. This is transcribed

Front 105

30‐nm fiber 

Back 105

Nucleosome arrangement, Zig Zag or Solenoid model.

Zig Zag = nucleosomes on alternating sides

Solenoid = nucleosomes on same side

Front 106

chromatin 

Back 106

condensed nucleoprotein complex.

Front 107

SMC protein 

Back 107

Structural Maintenance of Proteins

Front 108

heterochromatin 

Back 108

More condensed form of chromatin in Eukaryotic cell. This is NOT transcribed

Front 109

nucleosome 

Back 109

Beads on a string, 8 histone complex wrapped in DNA

Front 110

scaffold model 

Back 110

when 30nm chromatin fiber binds to protein scaffold to make loops

Front 111

histone 

Back 111

family of proteins that interact with DNA binding ( Beads on a string)

Front 112

telomere 

Back 112

Chromosome ends. essential for stability of chromosome.

Front 113

nick 

Back 113

deletion of a bond in DNA