Protein Synthesis Flashcards
How do genes control cell activities?
They control cell activities by producing proteins, many of which are enzymes.
What are proteins composed of?
amino acids
How many steps are in protein synthesis?
14
What is the 1st step of protein synthesis?
- The DNA double helix unwinds at the site of the gene that is going to produce a protein.
What is the 2nd step of protein synthesis? (2)
- RNA bases, which are present in the cytoplasm, move across the nuclear membrane.
- The RNA bases will match up with the complementary bases on the DNA strand
What is the 3rd step of protein synthesis?
- The enzyme RNA polymerase causes the sequence of RNA bases to join together to form messenger RNA.
- Each mRNA molecule has complementary bases to those on the DNA strand from which it was transcribed.
- A sequence of three bases of DNA or RNA is called a triplet or codon. They may have 3 possible outcomes:
- A start codon indicates the beginning of a gene (not involved in the production of the protein)
- Most codons in a gene specify particular amino acids
- A stop codon indicates the end of a gene (but is not involved in the production of the protein)
What is the 4th step of protein synthesis?
Every gene has one start codon, many codons specifying amino acids and one stop codon.
Define transcription
Transcription is the copying of a sequence of genetic bases from DNA onto messenger RNA (mRNA)
Where do the DNA strands separate?
in the nucleus
What is the 5th step of protein synthesis?
The mRNA moves from the nucleus to the cytoplasm
What is the 6th step of protein synthesis?
Ribosomes are made up of ribosomal RNA (rRNA) and protein.
What are ribosomes made up of?
ribosomal RNA (rRNA) and protein
Define an anticodon
An anticodon is a sequence of three bases (a triplet) on tRNA that are complementary to a sequence of three bases on mRNA
A sequence of three bases of DNA or RNA is called a triplet or codon. They may have 3 possible outcomes. Name these outcomes.
A sequence of three bases of DNA or RNA is called a triplet or codon. They may have 3 possible outcomes:
- A start codon indicates the beginning of a gene (not involved in the production of the protein)
- Most codons in a gene specify particular amino acids
- A stop codon indicates the end of a gene (but is not involved in the production of the protein)
What is the 7th step of protein synthesis?
- The mRNA strand forms weak bonds with the rRNA in a ribosome. This will be the site of protein synthesis