Biology, 17.09.2019 20:20 abbyramirez52
In the 1920s, bacteriologist fred griffith demonstrated that a heat-killed, infectious pneumococcus produced a substance that could convert a harmless form of the bacterium into a lethal one. fifteen years later, researchers prepared an extract from the disease-causing s-strain pneumococci and showed that this material could transform the harmless r-strain cells into the infectious s-strain form. this change to the bacteria was both permanent and heritable, suggesting that this "transforming principle" represents the elusive genetic material of the cells. but what kind of molecule was it? the researchers subjected their extract to a variety of tests to determine the chemical identity of the "transforming principle." in one experiment, they treated the material with enzymes that destroy all proteins. this treatment did not affect the ability of the extract to transform harmless bacteria into an infectious form. from this result, the researchers can conclude that:
Answers: 3
Biology, 22.06.2019 01:30
Aperson with age is more likely to catch diseases that healthy people usually don’t catch.what are these infections called?
Answers: 1
Biology, 22.06.2019 09:00
Which best describes this behavior? it is beneficial only to the males that do not fertilize eggs. it is beneficial only to the female workers that are not fertilized. it is beneficial to each one of the individual colony members. it is beneficial to the whole species, but not to all of the individual members.
Answers: 2
Biology, 22.06.2019 17:30
Adding more tributaries to a local river basin can have what effect?
Answers: 3
Biology, 22.06.2019 19:00
Iwill mark which of these statements best describes how nasa's kennedy space center benefits florida? it improve the average income of people. it encourages the use of science for entertainment. it produce more astronauts and space scientists in florida. it encourages people in florida to use space technology in homes.
Answers: 1
In the 1920s, bacteriologist fred griffith demonstrated that a heat-killed, infectious pneumococcus...
Mathematics, 06.05.2021 07:20
Mathematics, 06.05.2021 07:20
Mathematics, 06.05.2021 07:20
Mathematics, 06.05.2021 07:20
Mathematics, 06.05.2021 07:20