C: a column（柱壮物）of cells in the root apical meristem D: responsible for the absorption of water and minerals E: the central column of cells in the rootcap. 正确答案是E

3. The region of cell division in a growing root:

A: is responsible for most of the increase in length of the root. B: contains the apical meristem and nearby cells. C: contains most of the cells that are differentiating. D: contains root hairs.

E: is sharply delimited from the adjacent region. 正确答案是B

4. Root hairs arise from cells of the: A: vascular cylinder. （维管柱） B: pericycle.（中柱鞘） C: cortex D: epidermis. E: endodermis. 正确答案是D

5. In what root tissue are Casparian strips located? A: cortex B: epidermis

C: xylem and phloem D: xylem only E: phloem only 正确答案是A

6. Lateral roots arise in the: A: xylem B: epidermis. C: pericycle D: root hairs E: rootcap. 正确答案是C

7. In roots, phloem most commonly occurs: cork 正确答案是C

9. Which of the following statements about aerial roots is FALSE? A: They are adventitious （不定的）roots B: Some serve as prop（支持）roots.

C: They are produced from below ground structures.

D: If in contact with the soil they absorb water and minerals.

E: Red mangrove（红树林） and ivy（常春藤）produce aerial（气生的）roots 正确答案是C

10. Fleshy roots have an abundance of: A: xylem. B: phloem

C: parenchyma.

D: pericycle.（中柱鞘） E: endodermis 正确答案是C

Root and Plant Mineral Nutrition Part B

1. A short, upright（垂直的）, subterranean（地下的）stem covered by fleshy leaf bases is a ___. A: corm（球茎, 球根） B: bulb（鳞茎）

C: rhizome（根茎, 根状茎） D: stolon （匍匐茎） 正确答案是B

2. Roots that arise from leaves are termed ___. A: rhizomes （根茎, 根状茎） B: leaf roots

C: adventitious roots D: stolons （匍匐茎） 正确答案是C

3. Mucigel （粘胶质）formed by the root cap functions in ___. A: lubrication（润滑） B: water absorption C: protection

D: lubrication, water absorption and protection 正确答案是D

4. The region(s) of the root in which root hairs form is (are) the ___. A: region of maturation B: region of cell division C: region of elongation

D: regions of maturation, cell division and elongation 正确答案是A

5. The Casparian strip is associated with the ___. A: pericycle B: cambium C: endodermis D: cortex

正确答案是C

6. Branch or lateral roots form from the ___. A: division of the cambium B: pericyle

C: parenchyma of the cortex

D: specialized region of the endodermis 正确答案是B

7. A dicot（双子叶植物）root is characterized by the ___.

A: cambium forming xylem toward the central part of the root and phloem toward the outside B: cambium forming phloem toward the central part of the root and xylem toward the outside

C: location of discrete（不连续的, 离散的） vascular strands near the epidermis of the root D: random scattering（散射） of vascular strands throughout the root 正确答案是A

8. Roots that contain large amounts of aerenchyma are associated with ___. A: desert conditions

B: stagnant（停滞的）water C: deep lakes

D: alpine（高山的）regions 正确答案是B

9. Which term is least related to the others? A: epiphytes（附生植物, 真菌） B: epiphylls（叶附生植物） C: parasites（寄生虫） D: saprophytes（腐生物） 正确答案是D

10. The macronutrient（大量营养素）that regulates the osmotic（渗透的）pressure of guard cells is ___.

A: nitrogen（氮） B: sulfur （硫） C: potassium（钾） D: magnesium （镁） 正确答案是C

11. Which is a root?

A: Irish（爱尔兰的）potato B: rhizome（根茎, 根状茎） C: sweet potato

D: russet（黄褐色的, 赤褐色的）potato 正确答案是C

12. Iron is considered a macronutrient（常量营养元素）because it is needed for the synthesis of chlorophyll. A: True B: False

正确答案是B

13. The topsoil（表层土）of most fertile（肥沃的）, soils has a pH near 7.0. A: True B: False

正确答案是A

14. The tissue between the epidermis and the central vascular cylinder of the root is the cortex. A: True B: False

正确答案是A

15. Mycorrhizae function in absorption and are associated with roots. A: True B: False

正确答案是A

Root and Plant Mineral Nutrition Part C

1. Monocotyledonous plants （单子叶植物）generally have taproot（主根, 直根） systems with one or more primary and secondary roots. A: True B: False

正确答案是B

2. The root hair zone develops in the region of elongation. A: True B: False

正确答案是B

3. The enlarged root of the mainroot plant is specifically adapted for the storage of starch and other carbohydrates.（碳水化合物, 醣类） A: True B: False

正确答案是B

4. Lily bulbs are pulled deep into the soil by the action of contractile（会缩的, 有收缩性的）roots. A: True B: False

正确答案是A

5. In the root cap, amyloplasts（造粉体）function as gravity（重力）sensors（传感器）to keep the root growing downward. A: True B: False

正确答案是A

6. Roots that develop from a stem, leaf, or other plant part are called A: root hairs

B: adventitious roots. C: taproots（主根）

D: fibrous roots. （须根） 正确答案是B

7. In which region of the root is the apical meristem found? A: region of elongation B: region of maturation C: region of cell division D: root cap 正确答案是C

8. Which of the following statements about root hairs is NOT true?

A: They are tubular（管状的） extensions（延长, 扩充）, of epidermal cells. B: They develop into secondary roots.

C: They greatly increase the root's absorptive surface D: All of the above. 正确答案是B

9. What is the name given to the band of suberin（软木脂） surrounding the cells of the