4.2 Protein Synthesis Flashcards
1
Q
Define the genome
A
The complete set of genes in a cell
1
Q
Define the proteome
A
Full range of proteins that a cell is able to produce
2
Q
mRNA vs tRNA: Strands
A
Both single stranded
3
Q
mRNA vs tRNA: Shape
A
Linear vs Clover-leaf
4
Q
mRNA vs tRNA: Hydrogen bonding
A
No vs Yes
5
Q
mRNA vs tRNA: Ammount of codons/anti-codons
A
Many codons vs 1 anti-codon
6
Q
mRNA vs tRNA: Amino-acid binding site
A
No vs 1 binding site
7
Q
How does the base sequence determine the protein
A
- Read in triplets
- Determines order of amino acids
8
Q
Describe the process of transcription that is the same for both eukaryotes and prokaryotes
A
- DNA helicase breaks hydrogen bonds between complimentary base pairs
- DNA becomes unzipped
- Strands seperate, but only 1 is used as a template strand
- Free RNA nucleotides are attracted to and allgin with DNA bases by complimentary base pairing
- Hydrogen bonds form between adenine and uracil, and cytosine and guanine
- RNA polymerase catalyses the condensation reaction between adjacent nucleotides
- Forming **phosphodiester bonds **
9
Q
For eukaryotes, what is the final stages of transcription
A
- This is pre-mRNA
- Spliced by splicosomes to form mature mRNA
- By removing introns, and re-joining exons
10
Q
For prokaryotes what is the final stages of transcription
A
- mRNA is directly translated
- There are no introns
11
Q
Describe the process of translation
A
- mRNA leaves nucleus by nucelur pore
- Attaches and binds to ribosome in cytoplasm or RER
- Ribosome moves along mRNA until it reaches** start codon**
- Ribosome has 2 binding sites
- Allows tRNA anti-codon to bind to other binding site, bringing a specific amino-acid
- tRNA anticodon is completemtary to mRNA codon
- Ribosome moves along to next codon
- Peptide bonds form between adjacent amino-acids in condensation reaction, with use of ATP
- Process continues until stop codon reached
- tRNA molecule released after amino-acids join to form a polypeptide chain