1. Base your answer to the following question on the information below and on your knowledge of biology.

Transcription

1 Name SM Review Date Ms. Bottiglieri 1. Base your answer to the following question on the information below and on your knowledge of biology. Euglena are single-celled organisms that live in ponds. All euglena have chloroplasts and can make their own food. They can also take in food from the environment. The diagram below represents a euglena. An experiment was set up to determine the effect of nitrates, a pollutant, on the number of chloroplasts present in euglena. Five tanks were set up, each with euglena and a different concentration of nitrate solution: 0%, 0.5%, 1.0%, 1..5%, and 2.0%. The tanks were placed in a sunny location where each tank received the same amount of light. Which statement correctly identifies a variable in this experiment? A) The independent variable is the concentration of nitrate solution used. B) The dependent variable is the number of euglena placed in the tanks. C) The independent variable is the amount of sunlight. D) The dependent variable is the number of tanks used. 2. An experiment was carried out to determine whether drinking caffeinated soda increases pulse rate. The pulse rates of two groups of people at rest were measured. Group A was then given caffeinated soda and group B was given caffeine-free soda. One hour after drinking the soda, the pulse rates were measured. The participants in the experiment were all the same age, and they were all given the same amount of soda. What is the dependent variable in this experiment? A) type of soda given to each group B) amount of soda given to each group C) pulse rate of each group D) age of participants in each group

2 3. A student conducted an experiment to determine if listening to different types of music would affect pulse rate. She thought that pulse rate would change with different types of music. Each person participating in her experiment listened to seven different selections of music for 30 seconds each. The pulse rates were taken after each 30-second interval of music. Based on her experiment, the student concluded that a person's pulse rate changed when listening to different types of music. The component missing from this experiment is a A) prediction B) hypothesis C) control group D) research plan Base your answers to questions 4 and 5 on the information below and on your knowledge of biology. A scientist conducted an experiment to test the hypothesis that maple seeds exposed to acid rain will take longer to germinate than seeds exposed to normal rain, which has a ph of 5.6. The scientist set up four groups, each containing 200 maple seeds. The water used for each group had a different ph value: 5.6, 4.0, 3.0, and 2.0. All other conditions were kept the same. After ten days, the number of seeds that had germinated in each group was counted. 4. Identify the dependent variable in this experiment. 5. Identify the control group in this experiment. 6. Which statement describes the best procedure to determine if a vaccine for a disease in a certain bird species is effective? 7. Which apparatus shown below is serving as the control for the experiment? A) Vaccinate 100 birds and expose all 100 to the disease. B) Vaccinate 100 birds and expose only 50 of them to the disease. C) Vaccinate 50 birds, do not vaccinate 50 other birds, and expose all 100 to the disease. D) Vaccinate 50 birds, do not vaccinate 50 other birds, and expose only the vaccinated birds to the disease. A) A B) B C) Both A and B D) Neither A or B

3 8. A student is investigating the effect of different environmental factors on the growth of a certain species of bean plant over a period of 30 days. Which factor would not function as a variable in this investigation? A) species of bean plant B) soil moisture content C) amount of light D) atmospheric temperature 9. A student wanted to investigate the effect of varying concentrations of tryptophan on a bacterial culture. Several cultures of the same bacterial species were grown on media, each with a different amount of tryptophan. The cultures were then incubated at 37 C. At the end of 24 hours, the cultures were examined. As a control, the student should have used a culture that A) contained no bacteria B) was incubated at 25 C C) contained no tryptophan D) was not incubated 11. An experimental setup is shown in the diagram below. Which hypothesis would most likely be tested using this setup? A) Green water plants release a gas in the presence of light. B) Roots of water plants absorb minerals in the absence of light. C) Green plants need light for cell division. D) Plants grow best in the absence of light. 10. Which statement best describes a hypothesis? A) A hypothesis is the process of making careful observations. B) The conclusion drawn from the results of an experiment is part of a hypothesis. C) A hypothesis serves as a basis for determining what data to collect when designing an experiment. D) The facts collected from an experiment are written in the form of a hypothesis.

4 12. Many plants can affect the growth of other plants near them. This can occur when one plant produces a chemical that affects another plant. Design an experiment to determine if a solution containing ground-up goldenrod plants has an effect on the growth of radish seedlings. In your experimental design be sure to: state a hypothesis to be tested describe how the experimental group will be treated differently from the control group identify the independent variable identify the type of data that will be collected describe experimental results that would support your hypothesis Base your answers to questions 13 through 17 on the information below and on yom knowledge of biology. A chemical known as fertex affects external fertilization of sea urchin eggs. An experiment was set up using three tanks to investigate the effect of fertex. Each tank had a different concentration of fertex: 1%, 2%, and 3%. Ten sea urchin eggs and 2 ml of sea urchin sperm were added to each of the three tanks. A fourth tank was set up as a control. 13. Identify the independent variable in the experiment. 14. State one way to improve the validity of the experimental results. 15. State one example of the type of data that should be collected during the experiment. 16. Identify two factors that must be kept the same in all four tanks. Factor 1: Factor 2: 17. State one way the contents of the control tank would differ from the contents of the three experimental tanks.

5 18. Base your answer to the following question on the information below and on your knowledge of biology. Help for Aging Memories As aging occurs, the ability to form memories begins to decrease. Research has shown that an increase in the production of a certain molecule, BDNF, seems to restore the processes involved in storing memories. BDNF is found in the central nervous system and seems to be important in maintaining nerve cell health. Researchers are testing a new drug that seems to increase the production of BDNF. Design an experiment to test the effectiveness of the new drug to increase the production of BDNF in the brains of rats. In your answer be sure to: (1) State the hypothesis your experiment will test (2) Describe how the control group will be treated differently from the experimental group (3) Identify two factors that must be kept the same in both the experimental and control groups. (4) Identify the dependent variable in your experiment. 19. In a laboratory, spinach leaves exposed to continuous fluorescent light increased in vitamin content by 50 to 100 percent. Spinach leaves kept in darkness for a similar period of time either lost vitamin content or produced no gain. Describe how these findings could influence the way in which spinach is displayed for sale in supermarkets.