Molecular Biology Chapter 3 By David Clark

Front 1

base

Back 1

Alkaline chemical substance, in molecular biology especially refers to the cyclic nitrogen compounds found in DNA and RNA

Front 2

deoxyribonucleic acid (DNA)

Back 2

Nucleic acid polymer o which the genes are made

Front 3

deoxyribose

Back 3

The sugar with five carbon atoms that is found in DNA

Front 4

DNA

Back 4

Deoxyribonucleic acid, nucleic acid polymer of which genes are made.

Front 5

nucleic acid

Back 5

Class of polymer molecule consisting of nucleotides that carries genetic information

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pentose

Back 6

A five carbon sugar, such as ribose or deoxyribose

Front 7

phosphate group

Back 7

Group of four oxygen atoms surrounding a central phosphorus atom found in the backbone of DNA and RNA

Front 8

phosphodiester

Back 8

The linkage between nucleotides in a nucleic acid that consists of a central phosphate group esterified to sugar hydroxy groups

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ribonucleic acid (RNA)

Back 9

Nucleic Acid that differs from DNA in having ribose in place of deoxyribose.

Front 10

ribose

Back 10

The 5-carbon sugar found in RNA

Front 11

adenine (A)

Back 11

A purine base that pairs with thymine, found in DNA and RNA

Front 12

cytosine (C)

Back 12

One of the pyrimidine bases found in DNA or RNA and which pairs with guanine

Front 13

guanine (G)

Back 13

A purine base found in DNA or RNA that pairs with cytosine

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purine

Back 14

Type of nitrogenous base with a double ring found in DNA and RNA

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pyrimidine

Back 15

Type of nitrogenous base with a single ring found in DNA and RNA

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thymine (T)

Back 16

A pyrimidine base found in DNA that pairs with adenine

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uracil (U)

Back 17

A pyrimidine base found in RNA that may pair with adenine

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adenosine

Back 18

The nucleoside consisting of adenine plus (deoxy)ribose

Front 19

deoxynucleoside

Back 19

A nucleoside containing deoxyribose as the sugar.

Front 20

deoxynucleotide

Back 20

A nucleotide containing deoxyribose as the sugar.

Front 21

nucleoside

Back 21

The union of purine or pyrimidine base with a pentose sugar

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nucleotide

Back 22

Monomer of subunit of a nucleic acid, consisting of a pentose sugar plus a base plus a phosphate group

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ribonucleoside

Back 23

A nucleoside whose sugar is ribose (not deoxyribose)

Front 24

ribonucleotide

Back 24

A nucleotide whose sugar is ribose (not deoxyribose)

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antiparallel

Back 25

Parallel, but running in opposite directions.

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base pair

Back 26

Two bases held together by hydrogen bonds

Front 27

double helix

Back 27

Structure formed by twisting two strands of DNA spirally around each other

Front 28

hydrogen bond

Back 28

Bond resulting from the attraction of a positive hydrogen atom to both of two other atoms with negative charges

Front 29

right-handed helix

Back 29

In a right-handed helix, as the observer looks down the helix axis (in either direction), each strand turns clockwise it moves away from the observer

Front 30

base pairing

Back 30

A pair of two complementary bases (A with T or G with C) held together by hydrogen bonds

Front 31

complementary sequences

Back 31

Two nucleic acid sequences whose bases pair with each other because A, T, G, C in one sequence corresponds to T, A, C, G, respectively, in the other

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chromatin

Back 32

Complex of DNA plus protein which constitutes eukaryotic chromosomes

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chromosome

Back 33

Structure containing the genes of a cell and made of a single molecule of DNA.

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intergenic region

Back 34

DNA sequence between genes

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regulatory region

Back 35

DNA sequence in front of a gene, used for regulation rather than to encode a protein.

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centromere

Back 36

Region of eukaryotic chromosome, usually more or less central, where the microtubules attach during mitosis and meiosis

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kinetochore

Back 37

Protein structure that attaches to the DNA of the centromere during cell division and also binds the microtubules

Front 38

non-coding DNA

Back 38

DNA sequences that do not code for proteins or functional RNA molecules

Front 39

operon

Back 39

A cluster of prokaryotic genes that are transcribed together to give a single mRNA (i.e. polycistronic mRNA)

Front 40

telomerase

Back 40

Enzyme that adds DNA to the end, or telomere, of a chromosome

Front 41

telomere

Back 41

Specific sequence of DNA found at the end of linear eukaryotic chromosomes.

Front 42

central dogma

Back 42

Basic plan of genetic information flow in living cells which relates genes (DNA), message (RNA) and proteins

Front 43

chromosome banding techniques

Back 43

Visualization of chromosome bands by using specific stains that emphasize regions lacking genes

Front 44

karyotype

Back 44

The complete set of chromosomes found in the cells of a particular individual

Front 45

messenger RNA (mRNA)

Back 45

The molecule that carries genetic information from the genes to the rest of the cell

Front 46

replication

Back 46

Duplication of DNA prior to cell division

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amino acid

Back 47

Monomer from which the polypeptide chains of proteins are built

Front 48

polypeptide chain

Back 48

A polymer that consists of amino acids

Front 49

protein

Back 49

polymer made from amino acids; may consist of several polypeptide chains

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ribosome

Back 50

The cell's machinery for making proteins.

Front 51

S-value

Back 51

The sedimentation coeffient is the velocity of sedimentation divided by the centrifugal field. It is dependent on mass and is measured in Svedberg units

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transcription

Back 52

Conversion of information from DNA into its RNA equivalent

Front 53

translation

Back 53

Making a protein using the information provided by messenger RNA

Front 54

anticodon

Back 54

Group of three complementary bases of tRNA that recognize and bind to a codon on the mRNA

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codon

Back 55

Group of three RNA or DNA bases that encodes a single amino acid

Front 56

genetic code

Back 56

The code for converting the base sequence in nucleic acids, read in groups of three, into the sequence of a polypeptide chain

Front 57

ribosomal RNA (rRNA)

Back 57

Class of RNA molecule that makes up part of the structure of a ribosome

Front 58

transfer RNA (tRNA)

Back 58

RNA molecule that carry amino acids to a ribosome.

Front 59

antisense RNA

Back 59

RNA complementary in sequence to messenger RNA and which, therefore, base pairs with it and prevents translation

Front 60

ribozyme

Back 60

RNA molecule that acts as an enzyme

Front 61

alpha carbon

Back 61

The central carbon atom of an amino acid, to which the amino, carboxyl and R groups are attached.

Front 62

enzyme

Back 62

A protein or RNA molecule that catalyses a chemical reaction

Front 63

peptide bond

Back 63

Type of chemical linkage holding amino acids together in a protein molecule

Front 64

polypeptide bond

Back 64

Polymeric chain of amino acids

Front 65

R-group

Back 65

Chemical group forming side chain of amino acid

Front 66

amino- or N-terminus

Back 66

The end of a polypeptide chain that is made first and that has a free amino group

Front 67

carboxy- or C-terminus

Back 67

The end of a polypeptide chain that is made last and has a free carboxy-group

Front 68

cofactor

Back 68

Extra chemical group non-covalently attached to a protein that is not part of the polypeptide chain

Front 69

primary structure

Back 69

The linear order in which the subunits of a polymer are arranged

Front 70

prothetic group

Back 70

Extra chemical group covalently attached to a protein that is not part of the polypeptide chain

Front 71

quaternary structure

Back 71

Aggregation of more that one polymer chain in final structure

Front 72

secondary structure

Back 72

Initial folding up of a polymer due to hydrogen bonding

Front 73

tertiary structure

Back 73

Final 3-D folding of a polymer chain

Front 74

active site

Back 74

Special site or pocket on a protein where the substrate binds and the enzyme reaction occurs

Front 75

regulatory protein

Back 75

A protein that regulates the expression of a gene or the activity of another protein

Front 76

structural protein

Back 76

A protein that forms part of a cellular structure

Front 77

substrate

Back 77

The molecule altered by the action of an enzyme

Front 78

transport protein

Back 78

A protein that carries other molecules across membranes or around the body