Which one of the following can be used to measure the environmental and water quality?

#Question id: 11800

#Unit 6. System Physiology – Plant

There are at least three different types of companion cells in the minor veins of mature, exporting leaves. Which of the following statements about these companion cells is CORRECT?

 a.) transfer cells are transport sugars enter the apoplast during the movement of sugars from mesophyll cells to sieve elements. Transfer cells transport sugars from the apoplast to the symplast of the sieve elements and companion cells in the source.

 b.) the numerous mitochondria in companion cells may supply energy as ATP to the sieve elements

 c.) Ordinary companion cells can function in either symplastic or apoplastic short-distance transport in source leaves, depending in part on plasmodesmatal frequencies

 d.) Intermediary cells, by contrast, function in symplastic transport of sugars from mesophyll cells to sieve elements

#Question id: 11801

#Unit 6. System Physiology – Plant

Which one of the following compound most commonly transported in sieve elements of the phloem?

#Question id: 11802

#Unit 6. System Physiology – Plant

Damaged sieve elements are sealed off, but because of the processs that plug sieve plates pores, excuded phloem sap from wounds that sever sieve elements. Exudation of sap enhanced by the inclusion of;

#Question id: 11803

#Unit 6. System Physiology – Plant

Due to damage exudation of sap from cut petioles or stems takes place they can be collected. However, quantities of collected sap are small, and the method is technically difficult. A preferable approach for collecting exuded sap is to use an

#Question id: 11804

#Unit 6. System Physiology – Plant

P-proteins have been characterized at the molecular level. P-proteins from the genus Cucurbita consist of two major proteins;

#Question id: 11805

#Unit 6. System Physiology – Plant

P-proteins from the genus Cucurbita consist of two major proteins: PP1, the phloem filament protein, and PP2, the phloem lectin. Both PP1 and PP2 are thought to be synthesized in_______A___________and transported via the_______B_________to the_______C______, where they associate to form P-protein filaments and P-protein bodies.