#Question id: 10921
#Unit 6. System Physiology – Plant
The mechanism of phloem translocation in angiosperms is best explained by which method?
#Question id: 10920
#Unit 6. System Physiology – Plant
The pressure-flow model, first proposed by Ernst Münch, Phloem loading at the source and phloem unloading at the sink establish the pressure gradient.
a.) In source tissues, an accumulation of sugars in the sieve elements generates a lower or negative solute potential (ψs).
b.) source tissue, causes a steep drop in the water potential (ψ), due to water potential gradient, water enters the sieve elements and causes turgor pressure (ψp ) decrease.
c.) In sink tissues, phloem unloading leads to a lower sugar concentration in the sieve elements, generating a higher or less negative solute potential.
d.) As the water potential of the phloem rises above that of the xylem, water tends to leave the phloem in response to the water potential gradient, causing a decrease in turgor pressure in the sieve elements of the sink.
Which of the following statements of sink and source tissue is FALSE?
#Question id: 10919
#Unit 6. System Physiology – Plant
Both of these observations—________X__________and________Y__________—support the existence of mass flow in the sieve elements of the phloem.
#Question id: 10918
#Unit 6. System Physiology – Plant
The import into sinks such as developing roots, tubers, and reproductive structures, In many ways the events in sink tissues are simply the reverse of the events in sources. The following steps are involved in the import of sugars into sink cells such as;
#Question id: 10386
#Unit 6. System Physiology – Plant
During light-regulated plant development many seeds require light to germinate, a process called
#Question id: 10387
#Unit 6. System Physiology – Plant