D − 4, F − 6, H − 8, J − 10

TLS Online TPP Program

#Question id: 13204

#Unit 6. System Physiology – Plant

Many of the carriers of Sucrose–H+ symporters in the phloem play various role in transport, most of the transporters are found in source, path, and sink tissues. Some carriers are characterized such as;

a) SUT1, has high-affinity / low-capacity transporter found in the minor veins of source tissues, appears to be important in phloem loading.

b) Important role of SUT1 in phloem loading appears to be complemented by SUT4, which is low-affinity/high-capacity carrier

c) SUT2, appears to function as a sucrose sensor. This is indicated by findings showing that SUT2 is more highly expressed in sink and path tissues than in source leaves.

d) The major sucrose transporters in phloem loading into the companion cells and final uptake into companion cells appears to be the function of SUT4

Which of the following combination is correct?

TLS Online TPP Program

#Question id: 13203

#Unit 6. System Physiology – Plant

Intermediary cells are specialized companion cells that are involved in phloem loading in the plant. Which of the following pathway that have included the intermediary-type companion cells?

TLS Online TPP Program

#Question id: 13201

#Unit 6. System Physiology – Plant

Phloem loading in the apoplastic pathway thought to mediate the transport of sucrose from the apoplast into the sieve element– companion cell complex. Which of the following  are involved in such sucrose transporting by apoplast?

a) Sucrose is at a higher concentration in the sieve element–companion cell complex indicates that sucrose is actively transported against its chemical-potential gradient

b) Sugars transport from the apoplast into the sieve elements and companion cells energy driven process

c) Phloem loading in the apoplastic pathway involves a sucrose–H+ symporter

d) the route of phloem loading is−mesophyll cells→ bundle sheath cells→ phloem parenchyma cell→ ordinary companion cell→ sieve elements

Which of the following is incorrect?

TLS Online TPP Program

#Question id: 11743

#Unit 6. System Physiology – Plant

The wall between the two mature sieve tube elements contain a sieve plates, these sieve plate pores are open —that is, unobstructed by

TLS Online TPP Program

#Question id: 11742

#Unit 6. System Physiology – Plant

Mature sieve elements external view, showing sieve plates. The pores in the sieve plates between the sieve tube elements are open channels, what is the relevance of this open pores in the sieve plates?

TLS Online TPP Program

#Question id: 11741

#Unit 6. System Physiology – Plant

phloem transport indicating the importance of long distance transport in plants, the experiments demonstrated that removal of a ring of bark around the trunk of a tree, which removes the phloem. What will be its effect?