Author: Biology Junction Team

Scientific Method Web Quest: Compare Questions, Methods, and Evidence

Biology Foundations and Lab Skills Teaching Resources · High school biology; AP extensions where noted.

This guided reading task asks students to compare descriptions of scientific inquiry and then design a testable investigation on paper. The aim is to explain how evidence is used, rather than copy a list of steps from a website.

Learning goals and preparation

  • Distinguish questions, explanations, predictions, and evidence.
  • Compare a simplified classroom sequence with inquiry in practice.
  • Credit a source and explain an idea in original words.

Prerequisite: scientific method notes. Materials: paper or a document editor and access to the two readings below. The teacher should open the readings before assigning them; a printed excerpt selected under the source’s terms or a teacher explanation can replace web access.

Reading stations

  1. OpenStax: The Process of Science. Find how the reading distinguishes a hypothesis from a prediction and how evidence is used to examine an explanation.
  2. College Board: AP Biology Lab Manual Resource Center. Read the overview of inquiry-based investigations. Identify examples of decisions students can make about methods, measurements, or analysis. This is a source about teaching inquiry, not a required procedure for this activity.

Student response sheet

Record the title, organization, URL, and date accessed for each reading. In your own words, answer:

  1. What makes a question investigable with scientific evidence?
  2. How does a prediction differ from a proposed explanation?
  3. Why might a researcher return to an earlier question or revise a method?
  4. What useful role does a classroom sequence play? What does it leave out?
  5. How could observations contribute to an investigation without a manipulated treatment?

Apply what you learned

Plan a paper investigation of how water availability might affect seed germination. Define “germinated,” the measurement period, treatment levels, independent experimental units, conditions kept comparable, and an appropriate comparison. Explain what pattern would support your prediction and what alternative explanation would still need attention. No seeds, chemicals, or organisms are handled during this web quest.

Teacher feedback

A useful plan names observable outcomes and avoids treating “better growth” as a measurement. If seeds share a container, students should consider whether the container rather than each seed is the independently treated unit. A good response credits sources, distinguishes the two readings’ purposes, and acknowledges uncertainty. Do not require an “if–then” sentence as the only acceptable form of a scientific hypothesis.

Assessment: check accurate concepts, specific design choices, reasons for those choices, and source credit. For AP extension, ask students to identify a confound and propose a better sampling or treatment-assignment strategy.

Related teaching resources

Sources and further reading

POPULATION GENETICS PROBLEMS: HARDY-WEINBERG

POPULATION GENETICS PROBLEMS:  HARDY-WEINBERG EQUILIBRIUM

  1. A study on blood types in a population found the following genotypic distribution among the people sampled: 1101 were MM, 1496 were MN and 503 were NN. Calculate the allele frequencies of M and N, the expected numbers of the three genotypic classes (assuming random mating). Using X2, determine whether or not this population is in Hardy-Weinberg equilibrium.

 

  1. A scientist has studied the amount of polymorphism in the alleles controlling the enzyme Lactate Dehydrogenase (LDH) in a species of minnow.  From one population, 1000 individuals were sampled. The scientist found the following genotype frequencies: AA = .080, Aa = .280; aa = .640. From these data calculate the allele frequencies of the “A” and “a” alleles in this population. Use the appropriate statistical test to help you decide whether or not this population was in Hardy-Weinberg equilibrium.

 

  1. The compound phenylthiocarbamide (PTC) tastes very bitter to most persons. The inability to taste PTC is controlled by a single recessive gene. In the American white population, about 70% can taste PTC while 30% cannot (are non-tasters). Estimate the frequencies of the Taster (T) and nontaster (t) alleles in this population as well as the frequencies of the diploid genotypes.

 

  1. In another study of human blood groups, it was found that among a population of 400 individuals, 230 were Rh+ and 170 were Rh-. Assuming that this trait (i.e., being Rh+) is controlled by a dominant allele (D), calculate the allele frequencies of D and d. How many of the Rh+ individuals would be expected to be heterozygous?

 

  1. Phenylketonuria is a severe form of mental retardation due to a rare autosomal recessive allele. About 1 in 10,000 newborn Caucasians are affected with the disease. Calculate the frequency of carriers (i.e., heterozygotes).

 

  1. For a human blood, there are two alleles (called S and s) and three distinct phenotypes that can be identified by means of the appropriate reagents. The following data was taken from people in Britain. Among the 1000 people sampled, the following genotype frequencies were observed SS = 99, Ss = 418 and ss = 483. Calculate the frequency of S and s in this population and carry out a X2 test. Is there any reason to reject the hypothesis of Hardy-Weinberg proportions in this population?

 

  1. A botanist is investigating a population of plants whose petal color is controlled by a single gene whose two alleles are codominant. She finds 170 plants that are homozygous brown, 340 plants that are homozygous purple and 21 plants whose petals are purple-brown. Is this population in HWE (don’t forget to do the proper statistical test)? Calculate “F” (inbreeding coefficient) and explain what is happening in this population.

 

Click HERE for answers (but don’t go here until you’ve actually tried to answer these questions!)