DNA And Protein Synthesis

Question 1

What is gene expression

Answer 1

The process of making and controlling characteristics using transcription and translation

Question 2

What is RNA

Answer 2

Ribosomal nucleic acid

Question 3

What are the 3 types of RNA

Answer 3

mRNA (messenger RNA)
tRNA (transfer RNA)
rRNA (ribosomal RNA)

Question 4

Function of mRNA

Answer 4

To carry genetic messages that code for a particular protein from the nucleus (Where the DNA master copy is) to the cytoplasm (where protein is synthesized)

Question 5

Structure of mRNA

Answer 5

-single stranded
-contains one gene
-short lifetime (degraded soon after use)

Question 6

Structure of tRNA

Answer 6

-single stranded
-folds up into a clover leaf structure thanks to complementary base pairings
-There is always an ACC at one end of the molecule to bind it to its specific amino acid
-The middle loop has an anticodon complementary to a specific codon

Question 7

Function of tRNA

Answer 7

To bind the anticodon in the middle of the clover to the complementary codon on the mRNA
This ensures the correct order of amino acids

Question 8

Structure of rRNA

Answer 8

-rRNA with proteins from ribosomes
-They have two subunits one small and one large

Question 9

Function of rRNA

Answer 9

The site of translation
Assembled in the nucleolus of the nucleus
Free in the cell = make proteins for us in the cell
On the RER = make proteins for export

Question 10

Why do we do transcription

Answer 10

Proteins are synthesised in the cytoplasm so a copy of the genes need to be made to carry the genetic message from the nucleus to the cytoplasm

Question 11

1. Transcription

Answer 11

The RNA polymerase attaches to the promoter region of the genes and DNA helicase breaks the H bond between the RNA polymerase