A: translocation pores B: cytoplasmic streaming C: sieve plates D: companion cells 正确答案是C

4. A ___ is not an example of a modified改进的stem. A: cladophyll（扁平的叶状茎） B: thorn（刺, 棘, 荆棘） C: potato

D: petiole （叶柄, 柄部） 正确答案是D

5. The reactivation（再生作用)of the vascular cambium following a winter period is due to the ___.

A: action of auxin （生长素）

B: sensitivity（灵敏度）of the vascular cambium to auxin

C: sensitivity of the vascular cambium to gibberillin （赤霉素） D: sensitivity of the vascular cambium to auxin and gibberillin 正确答案是B

6. Which best characterizes growth rings? A: Each ring consists of one year's growth. B: Each ring is about 1 to 10 millimeters wide.

C: Each ring increases the diameter（直径）of the tree trunk（树干）

D: Each ring consists of one year's growth, is about 1 to 10 millimeters wide, and increases the diameter of the tree trunk. 正确答案是D

7. The periderm is formed from the ___. A: vascular cambium B: cork cambium C: apical meristem D: bark（树皮） 正确答案是B

8. Which plant represents a softwood? A: maple （枫木） B: oak （橡木） C: pine （松木）

D: dogwood （山茱萸） 正确答案是C

9. If the vascular cambium is active only in two opposite areas, the result is ___. A: production of large amounts of storage parenchyma B: stems that possess ridges C: stems that are round

D: stems that are flattened （被变平的） 正确答案是D

10. Which is the result of the cell arrangement in wood?

A: grain

B: texture（质地纹理）C: density（密度） D: durability,（耐久力） 正确答案是A

11. Phloem fibers function in the translocation of food throughout the plant. A: True B: False

正确答案是B

12. Spring wood is characterized as having small but many cells. A: True B: False

正确答案是B

13. Lateral conduction of food in a plant is accomplished.（完成的）via ray cells. A: True B: False

正确答案是A

14. Burning wood in the presence （存在）of very little oxygen results in charcoal.（木炭） A: True B: False

正确答案是A

15. The bark of a single tree species produces both cinnamon（桂皮）and quinine.（奎宁） A: True B: False

正确答案是B Stems Part C

1. Bundle scars mark the location（位置）water and food-conducting tissues within leaf scars. A: True B: False

正确答案是A

2. The protoderm（原表皮）gives rise to the epidermis and cuticle in stems and roots. A: True B: False

正确答案是A

3. Summer wood is composed of many large vessel elements and few tracheids. A: True B: False

正确答案是B

4. The wood of conifers（松类, 针叶树） consists primarily of vessel elements and laticifers（乳汁细胞）. A: True B: False

正确答案是B

5. Herbaceous（草本的）dicots（双子叶植物） have vascular bundles scattered（离散的） throughout the pith of the stem.

A: True B: False

正确答案是B

6. White potatoes are modified（改良的）stems with nodes（节点） called eyes. A: True B: False

正确答案是A

7. Which of the following cell is NOT produced by the vascular cambium? A: tracheids B: pith cells C: fibers

D: vessel elements 正确答案是B

8. Which type of stele（石细胞）consists of a solid core（核心）of xylem surrounded by a layer of phloem?

A: protostele（原生中柱）

B: eustele（真中柱〈存在于大多数裸子植物和被子植物的茎内〉） C: siphonostele（管状中柱） D: none of the above 正确答案是A

9. Which of the following tissue types is found in the periderm? A: vascular cambium B: cork

C: secondary phloem D: primary xylem 正确答案是B

10. What is the name given to latex（乳汁, 乳胶）-secreting cells found in the phloem of some plants?

A: stipules（托叶）

B: phelloderm（软木皮层） C: laticifers（乳汁细胞） D: lenticels（皮孔） 正确答案是C

11. Which of the following monocots（双子叶植物）can attain（达到） great heights as a result of continually dividing parenchyma? A: palm（棕榈） B: corn

C: rye（裸麦, 黑麦） D: redwood 正确答案是A

12. Which of the following is NOT a feature of all specialized stems? A: nodes（节点）

B: internodes（节间） C: axillary buds（腋芽）

D: none of the above 正确答案是D

13. Which of the following is an example of a corm（球茎, 球根）? A: grasses

B: crocus（番红花属, 番红花） C: sweet potatoes D: all of the above 正确答案是B

14. Strawberries（草莓） reproduce asexually（无性地） by using A: tubers（块茎）. B: bulbs（鳞茎）

C: runners（匍匐茎）.

D: cladophylls（扁平的叶状茎） 正确答案是C

Leaves and the movement of water Part A 1. Pinnately（羽状的）compound（ 复合的

） leaves have all of their leaflets（小叶） attached at the same point at the end of the petiole（叶柄）. A: True B: False

正确答案是B

2. Reticulate（网状的）venation（脉络）refers to the branching arrangement of veins（叶脉） in dicot leaves. A: True B: False

正确答案是A

3. Palisade（栅栏）parenchyma cells contain numerous（许多的）chloroplasts, and make up the upper（上面的）layer of the mesophyll（叶肉）in leaves. A: True B: False

正确答案是A

4. Bundle sheath（鞘）cells are large, thin-walled cells that occur in the leaf epidermis near the central vein. A: True B: False

正确答案是B 5. Tendrils（卷须, 蔓）are modified stem tissue, which curl（卷曲）around rigid（刚性的）objects A: True B: False

正确答案是B

6. In autumn, the green chlorophyll pigments break down revealing（有启迪作用的）pigments of other colors. A: True B : False