The LD 50 is a number scientists use in research to determine the dose of a toxin required to kill 50% of a population of organisms. Biologists in Louisiana have become concerned about cadmium levels in the water near New Orleans, and the chance that frogs will die out.

Scientists have performed an experiment on bullfrog tadpoles In Louisiana and the results are presented in the graph. The LD 50 for bullfrogs is reached

A) at about 6 mg per gallon per day.
B) at about 60% of surviving tadpoles.
C) somewhere around 11 mg per gallon per day.
D) somewhere between 2 mg and 3 mg per gallon per d

there are mainly three domains in biological classification namely; archaea, bacteria, and eukarya.

archaea includes all the prokaryotic cells which are characterized by their lipid membranes. they have branched hydrocarbon which is attached to glycerol through an ether linkage.

bacteria includes all the prokaryotic cells, the cell membrane of which are made up of the unbranched fatty acid chain. in addition, they are attached to glycerol through an ester bond.

eukarya includes all the eukaryotic cells, that is, the cells contain a nucleus and other membrane-bound cell organelles.

they can be autotrophic as well as heterotrophic, unicellular as well as multicellular

they include kingdoms like protista, plantae, animalia, fungi et cetera.

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explanation:

energy and particles

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her next move would be to use agarose gel electrophoresis to separate the dna molecules of varying length and create a dna fingerprint.