Unit 1 Lesson 2

4. To control or manage a process, such as how plants maintain water levels.
6. A living thing that can perform all the processes needed for life.
9. Unwanted substances or byproducts, such as excess oxygen or pollutants, that a plant must eliminate.
11. Cells in multicellular organisms that are organized to perform specific functions.
12. The energy-rich molecules produced in the leaf cells and transported throughout the plant body.
14. Small, tightly packed cells that make up the protective outer layer of a plant.
19. A root system with one large main structure that can grow very deep into the soil.
20. Chemical substances that build up on the shaded side of a stem to cause bending.
21. A structure, like a plant stem or leaf, made of different tissues functioning together.
22. A group of similar cells, such as vascular or dermal, that work together for a specific task.

1. Another term for gravitropism, describing how roots grow toward Earth.
2. A root system with many branching roots that spread out wide near the soil surface.
3. Vascular tissue made of hollow, tube-shaped cells that move water from roots to the rest of the plant.
5. A group of organs, such as the shoot or root, working together to perform body functions.
7. Tiny pores in a leaf that allow materials like water and air to enter and exit.
8. A change in plant growth in response to the pull of gravity.
9. A type of leaf coating that helps a plant prevent water loss.
10. The two specialized cells that control the opening and closing of a stoma.
13. The type of plant tissue that forms hollow tubes to transport water throughout the body.
15. The process where a plant grows toward a light source.
16. The process that uses energy from sunlight to convert water and carbon dioxide into sugars.
17. The specialized plant tissue that transports sugars made in the leaves downward to other areas.
18. The energy source plants capture to make their own food.