Houston BIO 1362 ASSIGNMENT – Presenting and Analyzing

Houston BIO 1362 ASSIGNMENT – Presenting and Analyzing

Subject: Biology    / General Biology

Question
Name_________________________ Bench _______ TA _______________________ HOMEWORK ASSIGNMENT (50 points)
Read Appendix I – Presenting and Analyzing Experimental Data (Blackboard) and answer the
following questions, on a separate sheet of paper:
1. Variables: (5 points)
a. Describe the difference between an independent and a dependent variable b. Describe the difference between a discrete and a continuous variable 2. An analysis was conducted to determine the number of graduating seniors accepted into the different
Texas medical schools in 2006. What type of graph would be the appropriate one to present these
data and why? (5 points)
3. Use the example experiment described below to practice graphing and evaluating data (20 points):
An ecologist observed that sugar maples seemed to dominate the understory of a forest
while the larger (older) trees were mainly white oaks. Are the maples replacing the oaks?
NULL HYPOTHESIS: There is no significant difference between the age distributions of
sugar maples and white oaks in this forest.
ALTERNATIVE HYPOTHESIS: Sugar maples and white oaks in this forest have different age
distributions. (Other alternative hypotheses are also possible).
The ecologist counts tree rings in a sample of trees throughout the forest and the
following data are collected on tree age (in years):
Type of tree Age range (yrs) Sugar maple 1 – 10
11-20
21-30
31-40
41-50
1 – 10
11 – 20
21 – 30
31 – 40
41 – 50
51 – 60
61 – 70
71 – 80
81 – 90
91 – 100
101 – 110
111 – 120
121 – 130
131 – 140 White oak Number of
trees
10
15
10
8
2
2
2
2
2
4
3
4
3
5
7
4
2
1
1 i) Graph the data on a sheet of graph paper (you may use Excel or PowerPoint)
ii) Describe the procedures a scientist would use to evaluate the hypothesis.
iii) Using the accepted terminology, state the conclusions of the experiment relative to
the hypothesis.
4. Read Appendix I, Part B, Statistical Tests and answer the following: (5 points)
a. If you computed a chi-square value of 4.0 with a df = 1, would you accept the null hypothesis?
Why? 5. Examples taken from Appendix I: (15 pts)
For the graphs that follow, write a brief description interpreting the graph (in the space provided)
and answer the questions. Description: b. At what temperature is the reaction rate highest? _______ Description: c. What is the range in mean monthly temperature in Clemson, SC, (approximately 34°N
latitude)? _______ Description: d. At what wavelengths does the phytochrome (both forms) absorb the most light? _______