Biology, 03.07.2020 21:01, isiahamccoy2149
A scientist isolates a microbe from a contaminated water source. She thinks that the organism might be a new bacteria that is capable of surviving in the presence of lead, a heavy metal. She makes tubes of growth medium containing either no lead, 0.1 mg lead, 0.25 mg lead, 0.5 mg of lead or 1 mg of lead. She inoculates each tube with the 10 x 10e3 cells of the new organism and then incubates the inoculated medium at 37-degree Celsius. After 48 hours, she examines the tubes of medium and finds that there is no growth in any of them. However, she finds that the bacteria grew fine in a medium that did not contain any lead. She decides to repeat the experiment using lower concentrations of lead than those she used initially. what conclusion can the scientist in this scenario make from her result
1) all contaminated water contains high levels of lead and other heavy metals
2) the amount of lead used in the experiment killed the bacteria being tested
3) all experiment should be repeated three times or more
4) lead-contaminated water does not contain any bacteria at all
5) the test bacteria take more than 48 hours to grow in the laboratory when incubated at 37 degree Celsius
Answers: 3
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Transmission electron microscope are best for viewing a) microorganisms in pond water b) internal organs of a mouse c)internal structures of a cell d) surface features of a specimen
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Biology, 22.06.2019 15:20, ashley232323
Suppose a particular species of tulip plant has three alleles for the gene that codes for flower color. the cr allele produces red tulips, the cp allele produces purple tulips, and the cw allele produces white tulips. cr is dominant over cp and cw, and cp is dominant over cw. for each of the following crosses, determine the expected ratio of offspring for each flower color. cr cp x cp cw cr cw x cp cw 1 red: 1 purple : 0 white, 1 red: 2 purple: 1 white, 2 red: 1 purple 1 white, 1 red: 3 purple : 0 white, 2 red: 0 purple : 2 white, 2 red: 2 purple : 0 white
Answers: 2
Biology, 22.06.2019 15:30, DogeDogeLove
When an object is moving away from you while still making a sound, the pitch of the sound is perceived to a. lower b. unchanged c. fluctuating d. higher
Answers: 2
A scientist isolates a microbe from a contaminated water source. She thinks that the organism might...
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