Scientific Method Questions

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ESSAY QUESTIONS
57. You are a writer for "Consumer Reports" magazine and you are asked to design an experiment to evaluate the effectiveness of three brands of whitening strips for teeth. Describe how you would do this using the scientific method. Include all of the steps, control group, experimental groups, and variables
Question: "Which whitening strip will whiten the best."
Hypothosis: "Whitening strip B will whiten the best."
Prediction: "If whitening strip B whitens the best then, samples tested with strip B with test whiter with a spectrophotometer."
Experiment: Set up five groups of sample dentures. Four of the five groups will be stained with coffee. The fifth group will be set aside as a before-control group. After staining one of the groups will be set aside as an after-control group. Each of the last three groups will be treated with one of the three kinds of strips according to the directions unique to the brand. Some of the variables to be concerned with is the consistency in the staining process and the uniformity on the denture material.

58. Your biology class is performing an osmosis experiment. You are given three identical stalks of celery and three salt solutions of varying solute amounts. The data table below compares the solute amount of the celery stalks to the solutions.

Solute Amount of the Solution Water Amount of the Solution

Solution A less than the celery stalk more water than the celery stalk
Solution B same as the celery stalk same water as the celery stalk
Solution C more than the celery stalk less water than the celery stalk

a). Identify which solution is isotonic, hypertonic, or hypotonic to the celery stalk cells
Hypotonic solutions have concentrations of dissolved solids that are less than the celery.
Hypertonic solutions have concentrations of dissolved solid are more than the celery.
Isotonic solutions are the same as the celery

b). Describe what happens when the celery stalk is placed into each of the respective solution.
In a hypotonic solution celery will absorb the water and be very stiff and rigid.
In a hyper tonic solution the celery will turn very soft and mushy.
In an isotonic solution the celery will remain the same.

59. Dihybrid cross. The kernels (seeds) on an ear of corn are all offspring of one set of parents. There are 2 pairs of alleles on separate homologous chromosomes (purple or yellow kernels on one pair, plump or shrunken kernels on another). Yellow (Y) is dominant to purple (y) and plump (P) is dominant to shrunken (p). If the genotype of parent plants are YyPp and yyPP, what are the expected probabilities of the ...