Gene Expression

Question 1

Genome

Answer 1

The complete set of nucleotide sequences encoded in the total DNA of an organism.

Question 2

Structural Gene

Answer 2

Sections of DNA that carry to instructions for production of a protein.

Question 3

Structural Gene

Answer 3

Sections of DNA that carry to instructions for production of a protein.

Question 4

Gene Expression

Answer 4

The ability of a gene to be transcribed.

Question 5

Genetic Code

Answer 5

The code the body uses to convert the instructions contained in the DNA into the proteins essential for life.

Question 6

Non-Coding DNA

Answer 6

The greater part of the DNA molecule that does not contain structural genes.

Question 7

Regulatory Gene

Answer 7

A non-coding segment of DNA that produces transcription factors for gene expression.

Question 8

mRNA

Answer 8

Messenger RNA; RNA molecule formed during transcription.

Question 9

Transcription

Answer 9

First step of gene expression, in which a particular segment of DNA is copied into mRNA.

Question 10

Codon

Answer 10

Triplet of nucleotides on mRNA specifying an amino acid.

Question 11

Split Gene

Answer 11

A gene that contains sections of non-coding DNA called exons (expressed as RNA and protein) interrupted by sections of DNA called introns.

Question 12

Inrons

Answer 12

A non-coding section of DNA within a split gene.

Question 13

Exon

Answer 13

A coding section of DNA within a split gene.

Question 14

Trimming

Answer 14

Removal of non-coding sections at the beginning and end of mRNA.

Question 15

Capping

Answer 15

The addition of methyl-Guanine at the start of the trimmed mRNA.

Question 16

tRNA

Answer 16

Small segments of a long tail of adenines at the end of mRNA.

Question 17

Anticodon

Answer 17

Triplet of nitrogen bases found on tRNA.

Question 18

rRNA

Answer 18

RNA component of a ribosome.

Question 19

Polysome

Answer 19

Chain of ribosomes that ‘read’ mRNA

Question 20

Translation

Answer 20

Production of a polypeptide sequence from a sequence of mRNA codons.

Question 21

Transcription Factor

Answer 21

A protein produced by regulatory genes that controls gene expression.

Question 22

Epigenome

Answer 22

A system of gene control outside of the DNA (‘Above the genome’).

Question 23

Heterochromatin

Answer 23

Chromatin tightly coiled around histone proteins in the nucleosome.

Question 24

Euchromatin

Answer 24

‘Relaxed’ chromatin that contains genes that can be transcribed.

Question 25

Histone Modification

Answer 25

Addition of chemical tags that vary the width between nucleosomes and so determine whether or not a gene can be transcribed.

Question 26

DNA Methylation

Answer 26

The addition of a chemical tag (a methyl group) to the start of a structural gene to block transcription.

Question 27

Dizygotic Twins

Answer 27

Each twin develops from a separate egg and each egg is fertilised separate from the sperm cell.

Question 28

Fraternal Twins

Answer 28

An alternative name to dizygotic twins.

Question 29

Monozygotic Twins

Answer 29

Twins that develop from one zygote, which splits and forms two embryos; since they have the same genotype, they are considered to be identical.

Question 30

Homeotic Gene

Answer 30

Any group of related genes that control the body plan of an embryo along the head-tail axis during early embryonic development.

Question 31

Homeobox

Answer 31

DNA sequence of about 180 base pairs) contained in a gene (e.g. the Hox genes) that is highly conserved and can bind to DNA to control gene expression.

Question 32

Homebox (Hox) Genes

Answer 32

A sub-group of homeotic genes that control the body plan of an embryo aling the head-tail axis.

Question 33

Hoz Protein

Answer 33

A transcription factor produced by a Hox gene.

Question 34

SRY Gene

Answer 34

The gene on the Y chromosome responsible for initiating male sex determination in humans.