HELP WITH 9th GRADE (HIGH SCHOOL ) BIOLOGY HOMEWORK!!!?
I'm really confused and would GREATLY appreciate it if you help me!!! It has to do with Independent and Dependent Variables!!! Here's the question:
Imagine you were asked to design an investigation to answer the following question: What effect does the wavelength of light ( in nanometers ) have on the productivity of potato plants (measured in biomass or mass of potatoes produced)?
1.) Clearly state the Independent Variable 2.) Clearly state the Dependent Variable 3.) Identify ATLEAST 3 variables which should be controlled 4.) Describe what you would use for your experimental group(s) 5.) Describe what you would use for your control group 6.) Describe the data you will collect. Is this quantitative or qualitative? Why ?
PLEASE HELP ME GUYS!!! THANKS SOOO MUCH.
Azul2016-08-18T10:55:24Z
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I'll just guide you through this. I'll give you the independent variable:
The independent variable is the type of wavelength because you get to change it. You would be using different wavelengths to test their effect on the potatoes. YOU decide which types of wavelengths you want to use for testing. So, it doesn't depend on other factors other than what YOU choose.
Dependent variable- Think about this: you are using different wavelengths to test what? What's going to change about the potatoes each time you use a different wavelength? Is it the color, the size, the taste, the amount of potatoes? Whatever it is, that is your dependent variable. This factor will depend on the wavelength you use. You don't decide what's going to happen with it, it just happens. That's why it's called the dependent variable, it depends on other factors. So, what is your dependent variable?
Controlled variables- What should be kept the same? Everything else that could alter your dependent variable. What other thing can make the potatoes (plants) more or less productive? You just want to know the effect of the wavelength on your dependent variable. If there are other important factors that could also have a big impact on it, you should use them in the same way and in the same amounts during the whole experiment. So, other than light, what factors can have an impact on plants?
Experimental group- Pretty simple, the group you're testing. It's the group where you are using the different wavelengths.
Control group- That's the one you want to keep under "normal" conditions to then compare it to the experimental group. Everything here is kept the same way as always. You don't change the wavelengths.
Quantitive or qualitative data- Think about the results you would get. How do you tell if the dependent variable changed and how do you measure your results? I won't tell you that. Use these links: http://www.regentsprep.org/regents/math/algebra/ad1/qualquant.htm http://www.shmoop.com/probability-statistics/qualitative-quantitative-data.html
I hope and pray that Yahoo answers isn't full of idiots who will hand out homework answers without a thought. You need to put forth an effort and show that you even attempted your questions. If you're in 9th grade and you can't find a single answer to one of these questions, you need serious help.