KEY CONCEPT Plants have specialized cells and tissue systems.

1. KEY CONCEPTPlants have specialized cells and tissue systems.

2. Parenchyma cells are the most common plant cell type. store starch, oils andwater help heal wounds tothe plant have thin flexible walls Plant tissues are made of three basic cell types.

3. they are strong and flexible. celery strings are strands of collenchyma. they have unevenly thick cell walls. • Collenchyma cells provide support to a growing plant.

4. second cell wall hardened by lignin die when they reach maturity used by humans to make linen and rope • Sclerenchyma cells are the strongest plant cell type.

5. Dermal tissue covers the outside of a plant. protects the plant secretes cuticle of leaves forms outer bark of trees Plant organs are made of three tissue systems.

6. provides support stores materials in roots and stems most commonly made of parenchyma • Ground tissue is found inside a plant.

7. two networks of hollow tubes xylem transports water and minerals phloem transports photosynthetic products stem leaf root • Vascular tissue transports water, minerals and organic compounds.

8. Plants passively transport water through the xylem. Cohesion is the tendency of water molecules to bond with each other. • The cohesion-tension theory explains water movement. • Adhesion is the tendency of water molecules to bond with other substances.

9. absorption occurs at roots • Water travels from roots to the top of trees. • cohesion and adhesion in xylem • transpiration at leaves

10. water vapor exits leaf stomata helps pull water to the top branches • Transpiration is the loss of water vapor through leaves.

11. Roots provide many functions. support the plant absorb, transport, and store nutrients root hairs help absorption Roots anchor plants and absorb mineral nutrients from soil.

12. vascular cylinder apical meristem root cap • There are several parts of a root. • root cap covers the tip • apical meristem is an area of growth • vascular cylinder contains xylem and phloem

13. grow underground for storage Strawberry stolons Stems support plants, transport materials, and provide storage. • Stems have many functions. • support leaves and flowers • house most of the vascular system • store water • form new plants

14. Secondary growth increases a plant’s width. • Primary growth increases a plant’s length.

15. The blade is usually broad and flat. collects sunlight for photosynthesis connects to the stem by a petiole blade petiole Most leaves share some similar structures.

16. Mesophyll is between the leaf’s dermal tissue layers. cuticle upper epidermis palisademesophyll spongymesophyll lowerepidermis

17. Stomata open and close when guard cells change shape. When stomata are open, water evaporates and gas exchanges. Stomata close at night and when plant loses too much water. stoma guard cells • Guard cells surround each stoma.

18. Leaves may be simple, compound, or double compound. Compound leaf Simple leaf Double compound leaf

19. Leaf veins may be parallel or pinnate. Parallel veins Pinnate veins

20. Leaf margins may be toothed, entire, or lobed. Toothed margin Entire margin Lobed margin

21. Leaves have many adaptations. • for extreme temperatures, ex: pine needles

22. Leaves have many adaptations. • for extreme temperatures, ex: pine needles • for water loss,ex: cactus spines

23. for aquatic environments, ex: water lily • Leaves have many adaptations. • for extreme temperatures, ex: pine needles • for water loss,ex: cactus spines • for getting food,ex: Venus’ flytrap