3.2 Polypeptide Synthesis processes

Question 1

What is Transcription

Answer 1

the process of turning genetic information stored in the DNA into an intermediary molecule mRNA

Question 2

What is mRNA

Answer 2

an intermediary molecule, that is a messenger ribonucleic acid that is single stranded and genetically similar to DNA. it contains ribose sugar not deoxyribose and instead of thymine its uracil

Question 3

First step of transcription

Answer 3

RNA polymerase binds to the promoter sequence upstream from a gene

Question 4

Second step of transcription

Answer 4

As RNA polymerase moves along the DNA strand , a small region of DNA is unwound

Question 5

Third step of transcription

Answer 5

RNA polymerase ‘reads’ the DNA template strand, matching complementary free floating nucleotides to create a chain containing the same coding information

Question 6

Fourth step of transcription

Answer 6

A mRNA is sequentially synthesised by RNA polymerase, as it continues to move along the DNA strand

Question 7

Fifth step of transcription

Answer 7

Terminator sequence and the transcription of DNA, and the newly formed mRNA molecule is released

Question 8

What is Translation

Answer 8

The process of turning information encoded as mRNA into a polypeptide chain

Question 9

Translation process

Answer 9

1. mRNA docks to a ribosome
2. the ribosome matches a complementary tRNA molecule to the mRNA by matching codon/anticodon sequences
3. A polypeptide bond is formed between adjacent amino acid molecules which they carry
4. the polypeptide chain is formed by continuous additions of amino acids
5. when a stop sequence is reached, ribosome release mRNA and polypeptide molecule
6. the polypeptide results in mature protein

Question 10

What is a genotype

Answer 10

the genome or genetic makeup of an organism

Question 11

What is a Phenotype

Answer 11

The outward appearance of an organism, including observable traits, biochemistry and physiology