Amagnified cross-sectional view of a horsetail stem shows the tube-shaped cells of xylem. what is their function?
1. reproductive system of alteration of generations
2. transport system that moves water
3. storage system for extra starch formed

How are extrusive rocks formed? magma gets trapped inside earth and cools to rock. volcanoes apply force to solid rocks and eject them. magma gets forced to earth’s surface and cools to rock. volcanoes trap lava inside earth, where it cools to rock.

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.

Agenus is a taxonomic grouping that identifies a collection of species. when a scientist discovers a new species, how is this species assigned to a genus