A. Suzie Q wants to know the effect of different colors of light on the growth of plants. She believes that plants can survive best in white light. She buys 5 ferns of the same species, which are all approximately the same age and height. She places one in white light, one in blue light, one in green light, one in red light and one in the closet. All of the ferns are planted in Miracle-Grow and given 20 mL of water once a day for 2 weeks. After the two weeks, Suzie observes the plants and makes measurements.

This question is incomplete, the complete part is: What is the independent variable in this experiment? A) The plant species B) The amount of water that each plant gets C) The amount of time D) The different types of light the plants were put under.

The answer is D

Explanation:

In an experiment, the INDEPENDENT VARIABLE is the variable that is changed or manipulated by the experimenter in order to effect a measurable response.

In this case, Suzie Q wants to know the effect of different colors of light on the growth of plants. She conducts this experiment using different colors of light namely: white light, green light, blue light, red light etc. This shows that the variable being changed/manipulated is the different colors of light. Hence, the INDEPENDENT VARIABLE is the DIFFERENT TYPES OF LIGHT THE PLANT WERE PUT UNDER.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."