Protein Synthesis Flashcards
Define gene expression?
How protein is produced by cells according to genetic code
Name two stages involved in protein synthesis?
Transcription and translation
What’s meant by transcription?
The way DNA genetic code in a gene copied to mRNA (messenger)
Where does the transcription stage take place?
Inthe nucleus
Describe what occurs during transcription?
1.Enzyme breaks the hydrogen bonds and the double helix unwinds at the gene only
2.Free RNA nucleotides enter from cytoplasm and link up complimentary
3.The RNA nucleotides are joined together by the enzyme RNA polymerase
What is the structure of a mRNA molecule?
1.start codon-starts protein synthesis
2.codons that code for particular amino acids
3.stop codon- ceases protein synthesis
Define translation?
mRNA genetic code is converted into protein
Where does translation stage take place?
Ribosome
What is the ribosome are up of?
Ribosomal RNA (rRNA)
What is a transfer RNA?
Triplet of bases called an anti codon
A certain amino acid on the other end
Describe what occurs during translation?
mRNA moves from the nucleus through the cytoplasm to the ribosome
It attaches to small subunit of the ribosome and held in place by rRNA
Start codon begins
tRNA molecules move into ribosomes carrying amino acids
tRNA anticodons link up complimentary to mRNA codons
Anticodons on tRNA leave the ribosome, leaving the amino acids behind in a certain sequence
The stop codon ceases
Amino acids bond forming a protein chain
What is the final step for protein synthesis to become functional?
Folding
Do all proteins fold the same way?
Depends on their role and function
What are the two types of proteins?
Fibrous/structural and metabolic protein
