Keywords 2

Question 1

Polycistronic mRNA

Answer 1

Prokaryotes: contains codons of more than one cistron and codes for more than one protein

Question 2

Constitutive

Answer 2

A gene that is transcribed at a relatively constant level

Question 3

Inducible

Answer 3

To cause an increase in the transcription of the RNA of a gene

Question 4

Catabolite repression

Answer 4

Allows micro-organisms to adapt quickly to a preferred carbon and energy source first

Question 5

Consensus sequences

Answer 5

The calculated order of most frequent residues found at each position in a sequence alignment

Question 6

Structural gene

Answer 6

Codes for any RNA or protein product other than a regulatory factor

Question 7

Regulatory gene

Answer 7

A gene involved in controlling the expression of one or more other genes

Question 8

Core promoter

Answer 8

A region of DNA that initiates transcription of a particular gene

Question 9

General (basal) transcription factor (GTFs)

Answer 9

Bind to specific sites (promoter) on DNA to activate transcription of genetic information from DNA to messenger RNA

Question 10

Transcriptional activator (repressor protein)

Answer 10

A protein that increases gene transcription of a gene or set of genes

Question 11

Transcription factor (sequence specific)

Answer 11

A transcription factor is a protein that controls the rate of transcription of genetic information from DNA to messenger RNA, by binding to a specific DNA sequence

Question 12

Enhancer

Answer 12

A short (50–1500 bp) region of DNA that can be bound by protein activators to increase the likelihood that transcription of a particular gene will occur

Question 13

DNA binding domain

Answer 13

An independently folded protein domain that contains at least one structural motif that recognises double- or single-stranded DNA

Question 14

Dimerisation domain

Answer 14

A macromolecular complex formed by two protein monomers, or single proteins, which are usually non-covalently bound

Question 15

Activation domain

Answer 15

Similar to transcription factor

Question 16

Cooperativity

Answer 16

An interaction between molecules that results in a stable physical association between those molecules

Question 17

Epigenetics

Answer 17

Study of heritable phenotype changes that do not involve alterations in the DNA sequence

Question 18

5-methylcytosine

Answer 18

A methylated form of the DNA base cytosine that may be involved in the regulation of gene transcription

Question 19

DNA methyltransferase

Answer 19

Family of enzymes that catalyse the transfer of a methyl group to DNA

Question 20

CpG islands

Answer 20

Regions with a high frequency of CpG sites

Question 21

Chromatin modification

Answer 21

The dynamic modification of chromatin architecture to allow access of condensed genomic DNA to the regulatory transcription machinery proteins, and thereby control gene expression

Question 22

Chromatin remodelling

Answer 22

The dynamic modification of chromatin architecture to allow access of condensed genomic DNA to the regulatory transcription machinery proteins, and thereby control gene expression

Question 23

Nucleosome

Answer 23

A basic unit of DNA packaging in eukaryotes, consisting of a segment of DNA wound in sequence around eight histone protein cores

Question 24

Histone code

Answer 24

The transcription of genetic information encoded in DNA is in part regulated by chemical modifications to histone proteins

Question 25

Histone acetylase

Answer 25

Enzymes that acetylate conserved lysine amino acids on histone proteins by transferring an acetyl group from acetyl-CoA

Question 26

Histone deacetylase

Answer 26

Class of enzymes that remove acetyl groups from an ε-N-acetyl lysine amino acid on a histone

Question 27

Euchromatin

Answer 27

A lightly packed form of chromatin that is enriched in genes, and is often under active transcription

Question 28

Heterochromatin

Answer 28

A tightly packed form of DNA or condensed DNA, which comes in multiple varieties

Question 29

Insulators/boundary elements

Answer 29

A type of cis-regulatory element known as a long-range regulatory element

Question 30

Genomic imprinting

Answer 30

An epigenetic phenomenon that causes genes to be expressed in a parent-of-origin-specific manner

Question 31

Translation

Answer 31

The process in which ribosomes synthesise proteins after the process of transcription

Question 32

Ribosome

Answer 32

Complex molecular machine that serves as the site of biological protein synthesis

Question 33

Amino acid

Answer 33

Organic compounds containing amine and carboxyl functional groups, along with a side chain specific to each amino acid

Question 34

Genetic code

Answer 34

Set of rules used by living cells to translate information encoded within genetic material into proteins

Question 35

Redundancy

Answer 35

Situations where a given biochemical function is redundantly encoded by two or more genes

Question 36

mRNA

Answer 36

Convey genetic information from DNA to the ribosome, where they specify the amino acid sequence of the protein products of gene expression

Question 37

tRNA

Answer 37

An adaptor molecule composed of RNA that serves as the physical link between the mRNA and the amino acid sequence of proteins

Question 38

rRNA

Answer 38

RNA component of the ribosome, and is essential for protein synthesis in all living organisms

Question 39

Codon

Answer 39

Unit that consists of 3 adjacent bases on a DNA molecule that determines the position of a specific amino acid in a protein molecule during protein synthesis

Question 40

Anticodon

Answer 40

Triplet of nucleotides in transfer RNA that is complementary to the codon in messenger RNA that specifies the amino acid

Question 41

Charged (aminoacyl)-tRNA

Answer 41

tRNA to which its cognated amino acid is chemically bonded (charged)

Question 42

Aminoacyl-tRNA synthetase (tRNA ligase)

Answer 42

An enzyme that attaches the appropriate amino acid onto its tRNA

Question 43

'Wobble base'

Answer 43

Pairing between two nucleotides in RNA molecules that does not follow base pair rules.

Question 44

Ribozyme

Answer 44

RNA molecules that are capable of catalysing specific biochemical reactions, similar to the action of protein enzymes

Question 45

Start codon

Answer 45

First codon of an mRNA transcript translated by a ribosome

Question 46

Stop codon

Answer 46

Nucleotide triplet within mRNA that signals a termination of translation into proteins

Question 47

A-site

Answer 47

First binding site in the ribosome