3.4.2 Protein synthesis

Name the two stages of protein synthesis

Transcription, translation

What does transcription change

DNA to RNA

What is made in the process of changing DNA to RNA

Pre mRNA

What separates the two strands of DNA

DNA helicase

What does DNA helicase do

Breaks hydrogen bonds separating two strands

What occurs after strands are separated

Free RNA nucleotides bind to complementary bases on the template strand

How many template strands are in transcription

Only one

What does RNA polymerase do

Binds adjacent nucleotides together with phosphodiester bonds

What is the final step of making pre mRNA

RNA polymerase binding adjacent nucleotides together

What bonds join adjacent nucleotides

Phosphodiester bond

How is mRNA formed

pre mRNA has its introns spliced out by spliceosome forming mRNA

How does mRNA leave the nucleus

Via nuclear pores to a ribosomes

What does translation transfer

RNA to amino acid

Give examples of proteins made by RER

Hormones, antibodies

Give examples of proteins made by ribosomes in the cytoplasm

Intercellular, enzymes

Give two examples of where proteins can be made / ribosomes are found

Cytoplasm, RER

What happens first in the ribosomes for translation

Triplet codons are lead by anticodons to tRNA molecules

Define anticodon

Specific to amino acids

Define tRNA

A single stranded RNA molecule, that folds into a cloverleaf shape

What bonds does tRNA contain and where

H bonds between complementary pairings

Where does the amino acid attach to on the tRNA

The binding site

What does tRNA do when it enters the ribosomes

Binds to complementary codons

What do ribosomes do to the formation of peptide bonds

Catalyses it

Where do peptide bonds form

Between the amino acids

What does rRNA then form

Polypeptides

What happens when a stop codon is reached

Translation stops

When translation stops what occurs

Polypeptides detaches from the ribosomes

Where are polypeptides processed

The Golgi apparatus

Define a genome

The complete set of genes present in a. cell

Define a proteome

The full range of proteins a cell can producehW

Why is the proteome larger than the genome

Due to the amount of post-translational modification of proteins in the Golgi body

Name two similarities between DNA and RNA structure

Both are polynucleotides of nucleic acids, both contain adenine, guanine and cytosine

Name 2 differences between DNA and RNA structure

RNA doesn't contain thymine, instead uracil, RNA contains ribose,

Describe two differences between the structure of tRNA and mRNA

tRNA is cloverleaf shapes, tRNA contains an anticodon

Describe what makes up ribosomes

rRNA and a protein