1.3 gene expression

Question 1

Gene expression definition

Answer 1

where genetic information of a gene of DNA is transcribed and translated to synthesise products such as proteins.

Question 2

Three types of RNA

Answer 2

mRNA
tRNA
rRNA

Question 3

mRNA definition

Answer 3

The type of RNA that is involved in transcribing a gene of DNA and transporting it from the nucleus to the ribosome.

Question 4

tRNA function

Answer 4

tRNA carries an amino acid to the ribosome in translation to bind with mRNA

Question 5

rRNA function

Answer 5

To be part of the ribosome

Question 6

Triplet definition

Answer 6

Three bases of RNA

Question 7

Codon definition

Answer 7

A triplet of bases on mRNA that code for an amino acid when mRNA binds with tRNA

Question 8

Anti Codon

Answer 8

Three bases of tRNA which bond with mRNA.

Question 9

Differences between RNA and DNA

Answer 9

RNA is single stranded whereas DNA is double stranded
RNA contains ribose sugar whereas DNA contains deoxyribose sugar
RNA contains Uracil whereas DNA contains thymine

Question 10

Transcription stage 2

Answer 10

Free RNA nucleotides approach the unzipped DNA strands.

Question 11

Order of gene expression

Answer 11

DNA
Transcription
mRNA
translation
tRNA
Ribosome
Protein

Question 12

Transcription definition

Answer 12

The process of making an RNA copy of a gene of DNA

Question 13

Transcription stage 1

Answer 13

DNA unwinds and RNA polymerase unzips the molecule by breaking apart the weak and temporary hydrogen bonds, exposing the bases.

Question 14

Transcription stage 3

Answer 14

Free RNA nucleotides find the complimentary bases on the DNA strand

Question 15

Stage 4 of Transcription

Answer 15

Weak and temporary hydrogen bonds form between the bases of DNA and the bases of the RNA free nucleotides.

Question 16

Stage 5 of transcription

Answer 16

The enzyme RNA polymerase bonds together the sugar phosphate backbone of the RNA strand

Question 17

Stage 6 of transcription

Answer 17

Weak and temporary hydrogen bonds break between the DNA and RNA, and then an mRNA primary transcript strand is formed, DNA redwinds into a double stranded helix.

Question 18

Stage 7 of transcription

Answer 18

The mRNA primary transcript undergoes RNA splicing, this is where introns which are non coding regions of RNA are removed from the mRNA strand and the exons, which are coding regions of RNA are compacted together, making the mature transcript strand small enough to leave the nucleus.

Question 19

Stage 1 of translation

Answer 19

The mRNA strand leaves the nucleus and travels to the ribosome.

Question 20

Stage 2 of translation

Answer 20

The tRNA strand collects an amino acid and travels to the ribosomes to bond with mRNA

Question 21

Stage 3 of translation

Answer 21

The codon of mRNA bonds with the anti codon of tRNA using complimentary base pairing.

Question 22

Stage 4 of translation

Answer 22

Peptide bonds form between the adjacent amino acids, forming a polypeptide chain.

Question 23

Stage 5 of translation

Answer 23

The tRNA strand will then collect another amino acid to repeat the process.

Question 24

Alternative splicing definition

Answer 24

Where a different set of exons are spliced together forming a different mature transcript and a different protein in RNA splicing.

Question 25

Polypeptide definition

Answer 25

A chain of amino acids held together by peptide bonds

Question 26

What is the protein function determined by

Answer 26

The protein shape and structure.

Question 27

What are phenotypes determined by

Answer 27

The proteins produced in gene expression

Question 28

How do polypeptide chains become proteins

Answer 28

The polypeptide chain folds together and hydrogen bonds bind the individual amino acids in place.