Which of the following are long, thin cells thatoverlap, are tapered end to end, and carry water?

a. parenchymab. sieve tube membersc. tracheidsd. companion cellse. phloem

Answer: c

Which of the following results from the directexpenditure of energy in a plant?

a. root pressureb. evaporation of water from the leavesc. water flowing into the root apoplastd. transpirational flowe. sap flowing down from the leaves to the roots

Answer: e

The rate of flow of water through the xylem isregulated by

a. passive transport in the pith.b. the force of transpirational pull.c. active transport by the sieve-tube members.d. the number of companion cells in the phloem.e. active transport by tracheid and vessel cells.

Answer: b

The driving force for the movement of materials in the phloem of plants is

a. gravity.b. a difference in osmotic pressure between the source and sink.c. root pressure.d. transpiration of water through the stomata.e. adhesion of water to vessel elements.

Answer: b

Which of the following has the lowest water potential?

a. root xylemb. stem xylemc. soild. air spaces in the leafe. root hairs

Answer: d

s p

s p

Bulk flow:Movement dueto pressure(tension)

Which of the following are long, thin cells thatoverlap, are tapered end to end, and carry water?

a. parenchymab. sieve tube membersc. tracheidsd. companion cellse. phloem

Answer: c

Which of the following results from the directexpenditure of energy in a plant?

a. root pressureb. evaporation of water from the leavesc. water flowing into the root apoplastd. transpirational flowe. sap flowing down from the leaves to the roots

Answer: e

The rate of flow of water through the xylem isregulated by

a. passive transport in the pith.b. the force of transpirational pull.c. active transport by the sieve-tube members.d. the number of companion cells in the phloem.e. active transport by tracheid and vessel cells.

Answer: b

The driving force for the movement of materials in the phloem of plants is

a. gravity.b. a difference in osmotic pressure between the source and sink.c. root pressure.d. transpiration of water through the stomata.e. adhesion of water to vessel elements.

Answer: b

Which of the following has the lowest water potential?

a. root xylemb. stem xylemc. soild. air spaces in the leafe. root hairs

Answer: d