Protein Synthesis Flashcards
Outline protein synthesis
It is how proteins are made
2 stages are transcription and translation
List some proteins found in body and why they are important
structural importance: eg collagen;keratin Enzymes: eg Digestive;metabolic pathways Hormones: eg insulin;thyroid hormones Neuropeptides; eg endorphins Transport: eg haemoglobin (O2), albumin Receptors; eg neurotransmitter and hormonal Antibodies eg Immunoglobins Ion channels; eg sodium channels
What is an amino acid
The building block of proteins.
Can be basic or acid. All acids have an amine component and an acid component. They differ only in atomic makeup of the R groups.
joined by Peptide bonds through process of water being released and amino joins with the acid of another.
Describe process of transcription
1st stage of protein synthesis.
Imfor flows from DNA to mRNA, which
Copys and carries message from nucleus to cytoplasm. Occurs in a specific area of gene.
Pre-mRNA - is a direct copy of the ‘area’ of where the gene is to be copied. (snips out unnecesarry DNA)
Happens in the cell. It then readies the mRNA to move out of nucleus and into cytoplasm
Describe process of translation and factors involved.
Occurs in cytoplam. Ribosome will latch onto the mRNA. the ribosome will start translating and moves along and reads the mRNA 3 codes at a time and calls in the nucleoties to put them in the right order, forming a polypeptide, until in comes to a termination codon (stop codon) it is like a full stop and the polypeptide falls off. And will then attach to the non coding strand to pair up. mRNA template (introns cut out) rRNA makes the ribosome…sits on mRNA and reads code, tRNA taxis amino acids to ribosome when it calls them.
Describe a codon
3 nucleotides…….Codes for an amino acid. 3 base sequence in mRNA (codon) (Triplets in DNA)
Anticodon (in tRnA) is complimentary sequence to that which codes for the amino acids…acts as a docking point and helps tRNA to stick to mRNA:happens each time ribosome has to read an exon.
4 letters and 64 codons makes up genetic code.
Elements that dictate switching a gene on and off in Transcription
Transcription factor, Promoter, tata box and RNA Polymerase : all dictate where RNA polymerase binds to RNA.
And Termination signal switches process off.
Reading code
mRNA always reads the same as the DNA code except U instead of T.
What is transcription?
this is the first stage of protein synthesis
What is translation
The second stage of protein synthesis
What is replication? And is it part of protein synthesis?
DNA has to replicate itself in order to create new cells, this process happens prior to the protein synthesis stage.
Explain extrons and introns
After mRNA takes a copy of DNA, Pre mRNA tidys up the bits that are snipped out, to form mRNA. which is only made up of the exons(coding sequence): they are all the blocks of code in the DNA. Intron is the bits in between.
Why if AUG significant?
AUG is like a flag (methinene AUG start codon) and the ribosome will start translating and moves along and reads the mRNA 3 codes at a time and calls in the nucleoties to put them in the right order, forming a polypeptide, until in comes to a termination codon (stop codon) it is like a full stop and the polypeptide falls off.
