DNA, Genes And Protein synthesis Flashcards
What is the genome?
The complete set of genetic information contained in the cells of an organism
What is the proteome?
The complete set of proteins that can be produced by a cell
Describe the structure of messenger RNA
A long single strand. Its base sequence is complimentary to the DNA it was transcribed from
Suggest an advantage of using mRNA rather than DNA for translation
Shorter and contains uracil = breaks down quickly so no excess polypeptide forms
Single stranded and linear = ribosome moves along strand and tRNA binds to exposed bases
Contains no introns
Describe the structure of transfer RNA
A single strand of around 80 nucleotides that is folded over into a clover leaf shape. On one end is an anticodon and on the opposite end is an amino acid binding site
What is produced by transcription?
mRNA
Where does transcription take place?
In the nucleus
Outline the process of transcription
DNA uncoils into two strands with exposed bases. One is used as a template
Free nucleotides line up next to their complementary bases and are joined together by RNA polymerase
What happens to mRNA after transcription?
In eukaryotic cells, pre mRNA must be spliced to remove introns, leaving only the coding regions. Then it moves out of the nucleus and attaches to a ribosome
What is produced by translation?
Proteins
Where does translation take place?
In the cytoplasm, on ribosomes
Outline the process of translation
The anticodon of tRNA attaches to complementary bases on the mRNA
Amino acids bonded to tRNA form peptide bonds, continuing to form a polypeptide chain until a stop codon is reached
This process requires ATP
