Chapter 2-3 Review Quizzes for State Test

To test that a fertilizer makes flowers produce more blooms, a student tests 6 plants of equal size that all get equal water and sunlight. For 3 of the plants she uses the fertilizer and 3 plants of the plants she does not use the fertilizer. They then count the number of blooms on all the plants for 6 weeks. What is the dependent variable? a. the number of plants in the control group b. the amount of water c. the number of flowers d. the fertilizer

the number of flowers

To test that a fertilizer makes flowers produce more blooms, a student tests 6 plants of equal size that all get equal water and sunlight. For 3 of the plants she uses the fertilizer and 3 plants of the plants she does not use the fertilizer. They then count the number of blooms on all the plants for 6 weeks. What is the independent variable? a. the number of plants in the control group b. the amount of water c. the number of flowers d. the fertilizer

the fertilizer

In biology class, pole bean seeds are placed in groups of 10 and wrapped in paper towels. The paper towels are dampened with solutions having a pH of 3.0, 4.0, 5.0, or 6.0. Another group is dampened with purified water. After three days, the class records the number of seeds that have germinated. What question is this experiment designed to test? a. how do bean seeds affect the pH of water? B. does pH affect how well bean seeds germinate? c. do bean seeds need water to germinate? D. will bean seeds germinate in three days?

does pH affect how well bean seeds germinate?

When conducting a controlled experiment in a laboratory, a scientist ___. a. only changes one variable at a time b. does not change any of the variables c. can change all the variables at the same time d. will not have enough data to form a hypothesis

only changes one variable at a time

A medical laboratory conducted an experiment to see if caffeine consumption has an effect on memory. In one afternoon, participants were asked to drink two cups of coffee every hour for four hours, to review a sequence of ten pictures, and then to recall each picture. Which of these is the dependent variable in this experiment? a. the amount of caffeine in each cup of coffee b. the number of pictures remembered by each participant c. the amount of coffee each cup holds d. the number of participants

the number of pictures remembered by each participant

A group of researchers conducted an experiment to discover whether sleep deprivation altered people's appetites. In an evening study conducted for a week, participants were allowed to sleep for only five hours each night. Then the amount of food eaten by each participant was observed. Which of the following would be an effective control for this experiment? a. average appetite of sleep-deprived people not involved in the experiment b. average appetite of well-slept people in the general population c. the same participants' appetites measured when they did not experience sleep deprivation d. the same participants after two weeks of sleep deprivation

the same participants' appetites measured when they did not experience sleep deprivation

Ryan is studying the germination of the marigold plant from its seeds. Which question can be answered by conducting an experiment? a. During which season do marigold seeds germinate the best? b. What role does water have in the germination of marigold seeds? c. What causes marigold seeds to germinate after absorbing water? d. Does the amount of moisture affect the germination rate of marigold seeds?

Does the amount of moisture affect the germination rate of marigold seeds?

James and Ryan plan an experiment to investigate the effects of exercise on heart rate. They test 35 students at their high school by having each student exercise for 3 minutes. Which of the following would be the best control for the experiment? a. all of the students should be in the same grade b. all of the students should perform the same exercise c. all of the students should have eaten the same lunch d. all of the students should be the same height

all of the students should perform the same exercise

When beginning an experiment in science class, students should first --- a. form a hypothesis b. select the kind of equipment they will use c. decide on the number of variables they will test d. consider safety rules and guidelines

consider safety rules and guidelines

A student conducts an experiment to test the hypothesis that an increase in carbon dioxide concentration decreases the rate of respiration in organisms. She performs a series of experiments to test the hypothesis. What should be the next step of the scientific investigation? a. form a hypothesis b. gather and analyze data c. repeat the experiment three times d. draw conclusions from the results

gather and analyze data

Which of these statements is TRUE about a scientific theory? a. it is never tested b. it is supported by consistent scientific evidence c. it becomes a hypothesis after it has been tested d. it is considered to be a fact

it is supported by consistent scientific evidence

Students wanted to test which acid was most effective at preventing hornworms from feeding on tomato plants. The students sprayed salicylic acid on one group of 15 tomato plants and jasmonic acid on a second group of 15 tomato plants. then students placed one hornworm, with a mass of 30 to 35 mg on each tomato plant. The students recorded the mass of the hornworms after one week. Which of these should the students do to make their conclusion more scientifically valid? a. they should spray each tomato plant with more than one acid b. they should place different kinds of worms on the tomato plants c. they should place more than one hornworm on each tomato plant d. they should determine the average mass of the tomato plants along with the mass of the hornworms

they should place more than one hornworm on each tomato plant

To test if using fertilizer increases crop production the 4-H club chooses three types of fertilizer to test in their garden. They use fertilizer A on the tomato plants, fertilizer B on the bean plants, and fertilizer C on the cucumbers. The squash plants receive no fertilizer. Throughout the growing season, the club tallied the number of tomatoes, beans, cucumbers, and squash that were harvested. How could the club improve the validity of their experiment? a. they should test at least one additional fertilizer b. they should obtain the mass of the vegetables instead of counting c. they should test all three fertlizers on each type of vegetable individually d. they should mix all three fertilizers to use on the squash plants.

they should test all three fertlizers on each type of vegetable individually

When testing the benefits of a new fertilizer on the growth of tomato plants, the control group should include which of the following? a. tomato plants grown in soil with no fertilizer b. tomato plants grown in soil with the original type of fertilizer c. tomato plants grown in a different type of soil with the new fertilizer d. tomato plants of different varieties grown in soil with the new fertilizer

tomato plants grown in soil with no fertilizer

When doing an experiment, it is important to follow all of these procedures except ___. a. wearing protective goggles b. arranging and organizing the work space neatly c. understanding the meaning of the safety precautions d. using smaller beakers before using larger beakers

using smaller beakers before using larger beakers