3.3 DNA to Proteins

Which of these is NOT a difference between immature mRNA and mature mRNA?

• Mature mRNA has a poly adenosine tail on the 3' end and immature mRNA does not.

• Mature mRNA has a methyl-guanosine cap on the 5' end and immature mRNA does not.

• Mature mRNA is folded into a specific shape due to its properties and immature mRNA is not.

• Mature mRNA is shorter than immature mRNA because the Introns are removed.

• Mature mRNA can leave the nucleus and immature mRNA cannot.

DNA contains all of the following nitrogen-containing bases EXCEPT

• adenine.

• uracil.

• guanine.

• adenine.

• thymine.

Rosalind Franklin used which technique to determine many of the physical characteristics of DNA?

• transformation

• transmission electron microscopy

• density-gradient centrifugation

• X-ray diffraction

• all of these

Each DNA strand has a backbone that consists of alternating

• covalent and ionic bonds.

• nitrogen-containing bases.

• hydrogen bonds.

• sugar and phosphate molecules.

• covalent and hydrogen bonds.

In the spiral staircase model of DNA, the rungs are

• deoxyribose sugars.

• nucleotide base pairs.

• phosphate groups.

• composed of all of these.

RNA polymerase assembles new strands

• in a 5' to 3' direction only.

• in a 5' to 3' direction building one strand and a 3' to 5' direction building the other strand.

• in a 5' to 3' direction building the first half of a strand and a 3' to 5' direction building the second half of a strand.

• in a 3' to 5' direction building the first half of a strand and a 5' to 3' direction building the second half of a strand.

• in a 3' to 5' direction on the "old" 3' to 5' strand.

Franklin worked most closely with

• Wilkins.

• Watson.

• Crick.

• Chargaff.

• none of these.

A linear stretch of DNA that specifies the sequence of amino acids in a polypeptide is called a(n)

• codon.

• intron.

• messenger.

• gene.

• enzyme.

The two steps of transcription followed by translation

• explain the structural complexity of genes.

• describe the flow of genetic information.

• are based upon the role of proteins in controlling life.

• do not explain how genes function.

• explain evolution in terms of molecular biology.

All of the different kinds of RNA are transcribed in the

• mitochondria.

• cytoplasm.

• ribosomes.

• nucleus.

• endoplasmic reticulum.