15. Gene Expression

How is the information encoded in DNA actually used by organisms?

Check your understanding of the flow of genetic information through a cell by filling in the blanks. a.b.c. d. e. f. g. h. i.

Which of the following is an important exception to the central dogma of molecular biology?a. Many genes code for RNAs that function directly in the cell.b. DNA is the repository of genetic information in all cells.c. Messenger RNA is a short-lived 'information carrier.'d. Proteins are responsible for most aspects of the phenotype.

What is the name of the process that produces RNA from a DNA template? What is the name of the process that produces a polypeptide from an RNA template?

A friend says, 'Geneticists spend all their time talking about DNA, but that's silly because DNA really isn't that important in the functions of a cell.' In what ways is she right, and in what ways might she be wrong?

A friend says, 'Geneticists spend all their time talking about DNA, but that's silly because DNA really isn't that important in the functions of a cell.' In what ways is she right, and in what ways might she be wrong?

Describe the process by which the information in a eukaryotic gene is transcribed and translated into a protein. Correctly use these words in your description: tRNA, amino acid, start codon, transcription, RNA splicing, exons, introns, mRNA, gene, codon, RNA polymerase, ribosome, translation, anticodon, peptide bond, stop codon.

The base sequence of the gene coding for a short polypeptide is CTACGCTAGGCGATTGACT. What would be the base sequence of the mRNA transcribed from this gene? Using the genetic code, give the amino acid sequence of the polypeptide translated from this mRNA. (Hint: What is the start codon?)