DNA, genes and protein synthesis Flashcards
What is a gene?
A section of DNA that contains the coded information for making polypeptides and functional RNA.
Name three features of genetic code.
- Degenerate,
- Non-overlapping,
- Universal.
Describe the DNA in prokaryotic cells.
Shorter, found in circles, not associated with histones.
Describe the DNA in a eukaryotic cell.
Longer, linear, associated with histones.
What is the diploid number in humans?
46
What is an allele?
One of a number of alternative forms of a gene.
What is a codon?
Sequence of 3 bases on mRNA what codes for a single amino acid
What is a genome?
The complete set of genes in a cell.
What is a proteome?
The full range of proteins produced by the genome.
How is the structure of mRNA suited to its function?
Possesses information in the form of codons. The sequence of codons determines the amino acid sequence of a specific polypeptide.
Describe the structure of tRNA.
Single stranded chain folded into a clover shape. The end of the chain is where the amino acid attached. The opposite end hold the anti-codon for binding to mRNA.
What enzyme breaks the hydrogen bonds between bases to expose them in a specific region of DNA?
DNA helicase.
What enzyme forms a phosphodiester bond between the free nuceotides forming the pre-mRNA?
DNA polymerase.
What does the ribosome do in translation?
Moves along the mRNA, bringing together two tRNA molecules at any one time.
