BIO (2010) - Scientific Investigation Questions

Students in a biology class thought that saltwater would affect the movements of Planaria. They put 25 Planaria in saltwater and recorded their observations. What flaw was present in the design of their experiment?

There was no control

A student's experiment showed that earthworms move away from light. This statement should be classified as —

a conclusion

A student soaked 50 lima bean seeds and 50 green bean seeds in water for 24 hours. Then she planted the seeds in soil at a depth of two centimeters, using the same amount of water, light, and heat for each kind of seed. She measured every three days to determine which type of seed grew the fastest. The paragraph describes —

an experiment

A student is investigating the effect of plants on indoor air quality and states, "If plants are added to an indoor environment, the air quality will improve." This statement is an example of —

a hypothesis

A scientist observes that a species of insect appears to be more numerous during dry summers than during wet summers. What is the next step to determine an explanation of this phenomenon?

Develop a hypothesis

A scientist develops a hypothesis, designs an experiment, and obtains data that support her hypothesis. What best describes how a hypothesis becomes a theory?

When it is supported by consistent data from many experimental trials

gather accurate data

Students use a dissolved oxygen probe during a laboratory activity involving 1,000 mL samples of pond water. The function of the probe is to -

A student hypothesizes that green algae will grow fastest when exposed to blue light. To test this hypothesis, the student should design an experiment with which independent variable?

Color of light that algae are exposed to

A student hypothesizes that green algae will grow fastest when exposed to blue light. In an experiment design, what would be the dependent variable?

Algae growth

A lab activity requires students to insert potassium hydroxide (KOH) pellets into a narrow tube to absorb carbon dioxide. Pellets of KOH are very caustic and alkaline. What is the safest way to put the pellets into the tube?

Use forceps to transfer the pellets

As part of their training, biologists learn the history of developments in their field of interest. Which best explains the importance of this education?

It gives biologists an understanding of their field so they can expand on earlier knowledge.

A scientist designed an experiment to test the effect of temperature on bacterial growth. He grew three different cultures of the bacterium E. coli under three heat lamps at different temperatures. What was the independent variable in this experiment?

Temperature

A scientist designed an experiment to test the effect of temperature on bacterial growth. He grew three different cultures of the bacterium E. coli under three heat lamps at different temperatures. What was the dependent variable in this experiment?

Bacterial growth

A student wanted to look at plant growth in five different soil samples. He planted the same type of seeds in identical containers and left them together in full sunlight. He gave each plant the same amount of water and charted the growth of each plant stem. What is the independent variable in this experiment?

Soil

A student wanted to look at plant growth in five different soil samples. He planted the same type of seeds in identical containers and left them together in full sunlight. He gave each plant the same amount of water and charted the growth of each plant stem. What are the constants in this experiment?

same seeds, identical containers, full sunlight, amount of water

A student wanted to look at plant growth in five different soil samples. He planted the same type of seeds in identical containers and left them together in full sunlight. He gave each plant the same amount of water and charted the growth of each plant stem. What is the dependent variable in this experiment?

Plant growth

A student plans to conduct an experiment to determine how a change in the pH of water affects the population growth rate of algae. To ensure that her experimental data are valid, she should —

use the same species of algae in all trials

A student plans to conduct an experiment to determine how a change in the pH of water affects the population growth rate of algae. What is the independent variable?

pH of the water

A student plans to conduct an experiment to determine how a change in the pH of water affects the population growth rate of algae. What is the dependent variable?

The population growth rate of the algae

A student plans to conduct an experiment to determine how a change in the pH of water affects the population growth rate of algae. What would be an appropriate control for this experiment?

an algae population with water that does not change pH

In an experiment, the height of several plants was recorded daily in millimeters. Which tool would be the most accurate and appropriate for this measurement?

Metric ruler

A student researching a new discovery about the activity of mitochondria could find the most current and reliable information in a —

scientific journal

A biology class of 24 students decides to measure the height of each student and then calculate the average height for the class. Which of these is a possible source of error in this activity?

The accuracy of making and recording measurements

Francesco Redi performed an experiment in 1668. In the experiment, he placed rotting meat in two jars. The first jar was left open. After a few days, fly larvae were found on the decaying meat inside. The mouth of the second jar was covered with gauze. After a few days, the decaying meat inside was free of fly larvae, but larvae were found on the gauze. This experiment supports the hypothesis that fly larvae only come from adult flies and helped to disprove -

the theory of spontaneous generation.

In 1869, DNA was discovered within the nuclei of cells. By the 1940s, scientists knew that chromosomes were made of both DNA and protein but did not know which was the genetic material of cells. In the 1950s, scientists demonstrated that DNA is the material responsible for heredity. In 1953, using information collected by other scientists, an American biologist and an English physicist built a three-dimensional model of DNA. These discoveries best illustrate the importance of —

collaborative efforts among scientists

What best explains why a student researching a topic should use the most recent peer-reviewed scientific journals and textbooks available?

New discoveries frequently add to older knowledge

Orchids were studied to determine if the amount of humidity affected the flowering of these plants. What was the independent variable in this study?

amount of humidity

Orchids were studied to determine if the amount of humidity affected the flowering of these plants. What was the dependent variable in this study?

flowering of the plants

Richard was observing black swallowtail butterflies in the field. Which one of these is an observation he made about a black swallowtail butterfly?

It laid its eggs on a parsley plant

In 1928, the scientist Alexander Fleming was trying to grow the bacterium Staphylococcus, and by chance, discovered that it would not grow in the presence of a mold that he named Penicillium. In 1939, Ernst Chain and Howard Florey purified penicillin, and in 1941, penicillin was first used to treat bacterial diseases. In 1945, Alexander Fleming, Ernst Chain, and Howard Florey received the Nobel Prize in medicine for the discovery and isolation of penicillin. These facts show that —

scientific progress often requires the efforts of many people working together

Henry's project is on porcupine populations in Virginia. He would like to use the phone book to help him make contacts. His most reliable contacts would probably be found by looking in the phone book under —

state agencies

What best states the importance of using control groups?

Control groups allow comparison between subjects receiving a treatment and those receiving no treatment.