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The table below contains information for various insecticides LD50s of various pesticides Chemical Synthetic/natural Oral LD50 in rats (mg/kg) Dieldrin Synthetic 40 Malathion Synthetic 885 Rotenone Natural (plant extract) 60 Pyrethrins Natural (plant extract) 200 With regard to oral toxicity in rats, from this table we can conclude:

A toxicologist is studying population of a small minnow that live in a pond near an industrial site that uses and discharges a variety of chemicals. They notice that an unusually high proportion of the minnows have tumors on their livers. Why might this be of concern? I. The minnows are important members of an ecosystem – if something is affecting their health it might impact the stability of the whole ecosystem. II. If the compounds that are making their way into the pond they may be making their way into other materials to which humans are exposed (air, well water, soil). The effect on fish might be an early warning for potential impacts on humans. III. There is no reason to be concerned about this, because fish and humans are very different. IV. There would only be reason to worry if this were happening in walleye or bass (fish humans eat).

The figure below shows the effects of nicotine and chlorpyrifos on brain development. From these data we can conclude:

Compounds that biomagnify are likely to

 The primary transcript in eukaryotes must undergo:  

According to the central dogma, the process by which information in an RNA molecule is used to direct the synthesis of a polypeptide is called  

Translation refers to:  

Gel electrophoresis separates DNA molecules based on variability in their  

Palindromic sequences:  

Selectable markers are used to: