1. Wild About Radishes 8 th Grade Inquiry Science Benchmark Assessment

2. Wild About Radishes Directions: Use the following information to answer questions 1 through 6. Amanda wanted to find out how acidic water affects plant growth. Amanda decided to do an investigation using radish plants and several water samples with different acidities as measured by pH. Question: What is the effect of the acidity of water on the height of radish plants? Hypothesis (prediction): Radish plants given water with a pH of 7 will grow taller than radish plants given water with a pH lower than 7 because plants will not grow well with water that is acidic.

3. Materials: radish seeds small plant pots filled with soil water samples each with a different acidity: pH 4, pH 5, pH 6, and pH 7 graduated cylinders labels ruler

4. Procedure: 1.Label six pots pH 4, six pots pH 5, six pots pH 6, and six pots pH 7 as shown in the Investigation Setup diagram. 2.Plant one radish seed in each pot. 3.Every three days pour 5 milliliters of water with the labeled pH into each pot. 4.Measure and record the height of the tallest leaf of each radish plant after watering. 5.After two weeks, calculate and record the average plant height for each of the four pH groups.

5. Data: The table below shows the calculated average plant heights for the six plants in each of the groups.

6. 1 Which variable was a controlled (kept the same) variable in this investigation? AA. p H of the water BB. S ize of the plants CC. L ength of the roots DD. V olume of the water

7. 2 Which variable was the manipulated (changed) variable in this investigation?  pH  pH of the water

8. 3 Which variable was the responding (dependent) variable in this investigation? AA. N umber of seeds planted BB. Time for plants to grow CC. Average plant height DD. Type of water

9. 4 In this experiment, all of the pots were the same size, shape and material. What is the purpose for controlling variables like these? AA. R educe the number of factors that could affect the height of the plants. BB. Increase the reliability of the plant height measurements. CC. Increase the reliability of the pH measurements. DD. Make the experiment more like a field study.

10. In your conclusion, be sure to: Answer the experimental question. Include supporting data from the Acidity of Water vs. Average Plant Height table. Explain how these data support your conclusion. 5Write a conclusion for this investigation.

11. Question: What is the effect of the acidity of water on the height of radish plants? The ideal pH of water for plant growth was 6, resulting in the tallest plant height. Water with pH of 4 or 5 only grew plants that measured.5 centimeters high. Water at pH 6 resulted in a plant height of 12.5 centimeters, which exceeded the pH 7 watered plant’s height of 9 centimeters. So water above or below pH 6 results in poorer plant growth, especially the lower pHs. Example:

12. 6 Plan a controlled experiment to answer the question in the box. You may use any materials and equipment in your procedure. In your procedure, be sure to include: logical steps to do the investigation one controlled (kept the same) variable one manipulated (changed) variable one responding (dependent) variable how often measurements should be taken and recorded Question: What is the effect of different amounts of pH 6 water on the height of radish plants?

13. Sample Procedure:  Label six pots 5 milliliters, six pots 10 milliliters, six pots 15 milliliters, and six pots 20 milliliters as shown in the Investigation Setup diagram.  Plant one radish seed in each pot.  Every three days pour the labeled amount of water into each pot.  Measure and record the height of the tallest leaf of each radish plant after watering.  After two weeks, calculate and record the average plant height for each of the four water volume groups.

14. 7 Which of the following do scientists use to learn about organisms that lived many years ago but are no longer alive today? AA. F ossils of organisms that lived many years ago, and DNA from the remains of organisms that lived many years ago BB. F ossils of organisms that lived many years ago, but not DNA from the remains of organisms that lived many years ago CC. D NA from the remains of organisms that lived many years ago, but not fossils of organisms that lived many years ago DD. S cientists have no way to learn anything about organisms that lived many years ago but are no longer alive today.

15. 8 The eye color of children often resembles the eye color of their parents. Which of the following is genetically passed from parents to children? AA. P articles of color are passed from parents to children. BB. C ells that become the colored part of the eye are passed from parents to children. CC. M olecules that contain the information that determines eye color are passed from parents to children. DD. N othing having anything to do with eye color is passed from parents to children.

16. 9 In many species of plants, reproduction can occur asexually (without the combining of two sex cells). Which of the following statements is TRUE about the DNA passed from parent to offspring in this type of reproduction? AA. A ll of the parent’s DNA is passed to its offspring. BB. H alf of the parent’s DNA is passed to its offspring. CC. N one of the parent’s DNA is passed to its offspring. DD. T he amount of DNA passed from parent to offspring varies from offspring to offspring.

17. 10 A species of bird ate many types of seeds, each type coming from a different species of tree. The birds' beaks varied in size, with some individuals having slightly smaller beaks and others having slightly larger beaks. A few years went by without much rain, and the only species of tree that survived had large seeds. Many generations later, almost all the birds had the slightly larger beaks. How is this best explained?

18. AA. T he birds with larger beaks were better at eating the large seeds than those with smaller beaks, so only the birds with larger beaks got enough food to survive, reproduce, and pass the trait of large beaks to the next generation. BB. T he birds with smaller beaks had to work harder than those with larger beaks to crack open the large seeds. The more they used their beaks, the larger their beaks became, so they were able to get enough food to survive, reproduce, and pass the traits of large beaks to the next generation. CC. T he birds with smaller beaks grew their beaks so that they would be better able to eat the large seeds and get enough food to survive, reproduce, and pass the trait of larger beaks to the next generation. DD. I t was a chance occurrence that all the individual birds' beaks in the next generation were larger. They were therefore able to eat the large seeds and get enough food to survive, reproduce, and pass the trait of large beaks to the next generation.

19. 11 Some animals have bones in their arms and hands that are similar to humans. If two animal’s bones are quite similar, it is evidence that their species are more closely related. Two animals with bones that are not very similar, are less closely related.

20. Based on this idea, name two of the animals above that are not closely related, and describe the evidence for your claim. Write your answer in this box:

21. There are many possible answers! Here is an example:  Bird and human are less related because bird has only 3 hand bones and human has 5.