Modern biologists have concluded that the beak shapes of the finches Darwin collected while on the Galapagos Islands are 

True or false? All ribosomes begin translation as free ribosomes. As protein synthesis begins, the protein itself will cue the ribosome to attach to the ER if necessary.

In the second level of DNA organization, the string of nucleosome beads coils to form the thick ______.

True or false? Most DNA mutations have either a neutral or negative effect on the resulting RNA or protein product.

Which of these is NOT a way in which viruses evolve?

In operon regulation, ______ means that the operator defaults to the “off” position—the genes are not being expressed unless an activator protein switches them off.

Which of these is NOT an important role of post-transcriptional mRNA modifications?

In order to amplify the sequence of the TAS2R38 gene, which of the following would be the appropriate primers to use?

T2 phage viruses are very simple; they are composed of DNA or RNA enclosed by a protein coat. When the phages are grown it is possible to radioactively label the DNA component only. For the second part of their experiment, Hershey and Chase allowed bacteria to be infected by the radioactively labeled T2 phage virus.  After allowing them to grow and reproduce, the bacterial cells were processed by centrifugation and the resulting pellet and supernatant were tested for radioactivity. What result do you expect?

Which of the following statements provides the best explanation for the presence of very small hind limb bones in whales?