TYPES OF QUESTIONS
Before answering a question, first determine the type of question being asked. The following sections provide examples of five types of frequently asked questions with suggestions on how to go about answering them.
Type 1: Definitions
These are straightforward questions that usually begin with the verb “define”. Answers are often easily found in the text glossary or by using the index to find page references.
Question: Define ecosystem.
Answer: The abiotic factors acting on a community of organisms in a geographical environment.
Type 2: Descriptions
These questions usually begin with such verbs as: “describe”, “specify”, “provide examples of”, “characterize”, etc. Answers include the information required with an appropriate level of detail (judge by the number of marks allotted). No explanations are required for these types of questions.
Question: Describe a desert ecosystem.
Answer: A desert ecosystem is a community of organisms that can survive in a geographical area that is subject to temperature extremes and less than 250 mm of precipitation annually.
Type 3: Comparisons
When answering a comparison question, state the item being compared and then indicate how each organism, process, site, etc., complies with this item. Questions that ask you to “compare and contrast” or “compare” imply that similarities and differences are to be included. Questions that ask you to “distinguish between” require you to include only the differences.
Question: Distinguish between the type and amount of vegetation in a desert and a forest and at the same latitude and elevation.
Answer: In a desert the plants would have adaptations for conserving water, such as, thick waxy cuticles, tissues that can store water (e.g. stems of succulent plants) and physiological adaptations such as C4 photosynthesis. You would not expect to see these adaptations in forest plants. Desert plants might be very small, close to the ground and very sparse. In contrast in a forest, the plants can be very large (e.g., trees can have large diameters and grow very tall) and vegetation can be very dense. The rate of photosynthesis in desert producers may increase dramatically after a rainfall whereas in a forest the rate of photosynthesis might change on a more regular basis e.g., with time of day and season.
Type 4: Explanations
This type of question requires answers that go beyond straightforward descriptions. Biological reasons must be logically presented and supported with information from field trips, lab exercises and texts as appropriate.
Question: Explain why deserts are subject to extreme variation in daily temperature.
Answer: Deserts are subject to extreme variation in daily temperature because of the low humidity (low moisture in the air). During the day, most of the radiation from the sun is absorbed by the substratum, warming the area. At night, there is little water in the air to hold in the heat so it radiates back into space, quickly cooling off the area.
Type 5: Discussion
This is an open-ended type of question. Sometimes “discuss”, “comment on” “account for” “speculate on”, etc., will appear somewhere in the question. In other questions, this is implied. Your first task is to determine what the question is asking. Then, decide what biological information you must introduce in order to provide a “biologically correct” and logical argument. Finally, organize your arguments in a clear and appropriate fashion. Do not include extraneous information; be succinct. There may be several “correct” answers to this type of question and your answer will be evaluated on the logic of your argument as well as your understanding of the biological nature of the problem.
Question: Tumbleweeds (Salsola tragus and S. kali) are the dominant plants in deserts in the American west yet they are rarely found in non-desert environments. Discuss possible reasons for this distribution of tumbleweeds.
Answer: Take the following steps to answer this question:
1. Determine what the question is asking: Why are tumbleweeds dominant in the desert and rare in non-desert environments, i.e., what are the characteristics of tumbleweeds that could favour these species only in the desert?
2. Summarize the facts necessary to answer this question: Tumbleweeds are annual plants that use water efficiently. Each plant can produce over 100,000 seeds which can germinate in a wide range of temperatures without requiring a lot of moisture. They grow quickly but only reach a maximum height of about 1 m. In non-desert environments, where water is more available, some shrubs and trees are much taller than 1 m.
3. Organize the arguments and then answer the question: Tumbleweeds are dominant in deserts because they use water efficiently and grow quickly, producing many seeds which can germinate in a wide range of temperatures without requiring a lot of moisture. Thus, in a desert environment they can outcompete other species. In ecosystems with greater water availability, the short-lived tumbleweeds have less vegetative growth than the perennials (e.g., grasses, trees) which can outcompete the tumbleweeds for light.
Always read over your answer to check for spelling and grammar errors and to make sure you have answered the question that has been asked.