After reading the paragraph below, answer the questions that follow. Researchers set up a study to determine whether large doses of a nutritional supplement would shorten the length of time it takes to recover from a cold. Three thousand volunteers were split into two groups. For two weeks, members of group A took 3,000 mg of the supplement daily. Group B received 3,000 mg of a placebo (sugar pill). At the end of the two-week period, the Tesearchers inserted live cold viruses directly into the noses of all the volunteers. The volunteers in both group A and group B continued to take their daily pills. All the volunteers got colds, and there was no significant difference in the length of time the colds lasted.
1. Which was the experimental group?
A) group A only
B) group B only all 3,000 volunteers
2. To have confidence that the results of the experiment were valid, you'd also want to know:
A) whether any volunteers had colds at the start of the experiment.
B) whether the volunteers exercised daily.
C) whether the volunteers all worked for the same company.
After reading the paragraph below, answer the questions that follow Researchers have created a robot that has a very thin leg that is moved by cardiac (heart) cells contracting in unison. The robot, made of a polymer similar to that used in making contact lenses, is bathed in heart cells with supporting cells, which then attach to the robot and provide movement as they contract.
3. If the creators of the robot wanted to provide evidence that it is alive, which of the following properties would be best to use as evidence?
A) The robot can move. "
B) The robot must be bathed in a liquid medium to provide nutrition for its cells.
C) New robots can be reproduced by researchers using the same manufacturing process.
D) The robot has two different types of cells, fibroblasts and cardiac cells.
4. All of the cardiac cells working together can cause the robot leg to move in a way that individual cells could not. This is an example of:
A) adaptation.
B) emergent properties of cells.
C) energy flow through an ecosystem.
D) internal environment regulation.