Geologic time is divided into units based upon types of
a.
sedimentary rocks
c.
organisms
b.
climatic changes
d.
igneous rocks

Astudy was performed on 20 trees to test the effectiveness of a new fertilizer. the results of this specific study is brought into question. what would possibly improve the reliability of the results?

In what way are cities microclimates?

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. 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. emergent properties of cells. b. energy flow through an ecosystem. c. adaptation. d. internal environment regulation.