What observation led researchers to propose that chloroplasts evolved from cyanobacteria? a) both produce proteins. b) both contain mitochondria. c) both provide structure to cells. d) both perform photosynthesis.

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.

Where are the strongest jet streams located?

This rapid change in species that rarely leaves behind fossil evidence is referred to as