In 1953, Watson and Crick were able to propose a model of DNA as a helical molecule with a sugar-phosphate backbone on the outside of the molecule. Which of the following earlier discoveries was most instrumental to this important discovery? By studying this photograph, scientists gained knowledge about the —
A. the discovery by Hershey and Chase that only DNA from a virus need enter a bacterial cell to cause an infection
B. X-ray crystallography studies of DNA conducted by Rosalind Franklin in 1951
C. the identification of DNA as the agent of bacterial transformation by Oswald Avery
D. the 1948 discovery by Linus Pauling that proteins take the shape of an alpha helix

The endoplasmic reticulum (er) is an organelle in some cells. in these cells, it is continuous with the nuclear membrane and forms a large part of the cell\'s total membrane. sort the phrases below as describing rough er, smooth er, both, or neither. note: if you answer any part of this question incorrectly, a single red x will appear indicating that one or more of the phrases are sorted incorrectly.1) found in prokaryites and uekaryotys2) involved in protein synthesis3) involve in lipid synthesis4) contains molecular chaperones in lumen5) bound with ribosomes6) involved in toxin or drug metabolism7) large systemot internnected tubules, vesicles, and sacs8) "packages" enzymes in vesicles for secretion.

What pattern of migration do whales follow?

Drag each tile to the correct location. match each trait that an organism displays to a reproductive strategy.