Several Different Researchers Contributed to the Study of the Structure

question 31

Multiple Choice

Several different researchers contributed to the study of the structure of DNA. What did Erwin Chargaff contribute?

• A) X-ray crystallography was used to show DNA is a repeating helical structure
• B) The percent of adenine is equal to the percent of thymine and the percent of guanine is equal to the percent of cytosine
• C) There is a transforming factor that exists and can change bacteria's characteristics
• D) Transformation of bacteria did not occur with the addition of DNase enzyme, suggesting DNA is the genetic material

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Definitions:

Olfactory Tract

Nerve tract that projects from the olfactory bulb to the olfactory cortex.

Transmembranous Receptor

Proteins spanning across the membrane of cells that receive chemical signals from outside the cell and initiate a response within the cell.

Odorant

A substance that is capable of producing a smell, often detected by the olfactory system.

Olfactory Neurons

Specialized nerve cells responsible for the sense of smell, located in the nasal cavity.