Unit Test Answers

How can a liquid be drawn into a pipette safely?

In a scientific investigation of lakes, the depth of a lake is most likely to be measured in

Which waste items should always be discarded in the hazardous waste container?

A small amount of chemical splashes in Frank’s eye. What should Frank do immediately?

Which description indicates that a question is nonscientific?

Dr. Katherine Pollard, a biostatistical researcher, recently changed the method that she used to compare human and chimpanzee DNA. Her research showed that the differences between the two species’ DNA are in segments called switches, which turn certain genes on or off. What is the most likely outcome of Dr. Pollard’s research?

What is the main purpose of controlled variables in an experiment?

The students are performing an experiment that involves chemicals.Based on the picture, what safety practice did both students fail to carry out?

A student is investigating the question “Which increases a person’s breathing rate more after three minutes, lifting five-pound weights or lifting ten-pound weights?” She designs an experiment to test the question. Which is the dependent variable in her experiment?

Dani wants to measure the volume of a pebble. Which tool will give the most accurate measurement?

Which subject is most likely to be studied by a biologist?

As one story goes, the famous 20-century physicist Niels Bohr and his team were interviewing a young man for a job. As part of the interview, the man described a hypothesis he had developed. A few days later, the man returned to find out whether he had been hired. Bohr greeted him with these words: "We are all agreed that your hypothesis is crazy. What divides us is whether it is crazy enough to be correct." The man was hired. What example of scientific thinking does Bohr's response best indicate?

Sometimes new information results in minor changes to a theory. But sometimes new information results in a theory being discarded as incorrect. An example of an incorrect theory that was disproved by the discovery of new information is

Sarah performs an experiment to see whether bees prefer red flowers or yellow flowers. Look at this table of results from the experiment. Number of bees found on yellow flowersNumber of bees found on red flowersDay 11214Day 21020Day 31418Day 41215What is the independent variable in this investigation?

After observing a moth that is camouflaged against dark-colored bark, a scientist asks a question. The scientist discovers that the question has already been asked and answered by several investigations. What should the scientist do?