Protein Synthesis Flashcards
What does DNA control in a cell?
The production of proteins (protein synthesis).
What are proteins made up of?
Chains of molecules called amino acids.
What does each different protein have?
Each different protein has its own particular number and order of amino acids.
Why can each protein have a different function?
The amino acids fold up to give each protein a different, specific shape, which means that each protein can have a different function.
This is why enzymes have active sites with a specific shape, and so only catalyse a specific reaction.
What is a gene?
A section of DNA that codes for a particular protein.
What in a gene decides what protein is produced?
The order of the bases in a gene decides the order of amino acids in a protein.
What is a base triplet?
A sequence of three bases in a gene that codes for each amino acid.
How much of an organism’s DNA makes up it’s genome?
All of an organism’s DNA (including the non-coding regions) makes up the organism’s genome.
What is a mutation?
A rare, random change to an organism’s DNA base sequence that can be inherited.
If a mutation happens in a gene, what is produced?
A genetic variant (allele) is produced - a different version of the gene.
What may the genetic variant code for?
A different sequence of amino acids, which may change the shape of the final protein and so its activity.
For example, the activity of an enzyme might increase, decrease or stop altogether.
What could a change in enzyme activity end up changing?
A change in enzyme activity could end up changing the characteristics (phenotype) of an organism.
What are the two stages of making proteins?
1) Transcription
2) Translation
In the cell cytoplasm, where are proteins made?
In subcellular structures called ribosomes.
Why can’t DNA in the cell nucleus move out of it?
Because it is really big.
