Following statements are regarding to dynamics of actin filaments.

A. When the concentration of G-actin is above the Cc, the filament end will grow; when it is less than the Cc, the filament will shrink.

B. ATP–G-actin is added much faster at the (+) end than at the (−) end, resulting in a lower critical concentration at the (+) end than at the (−) end.

C. At steady state, actin subunits treadmill through a filament. ATP-actin is added at the (+) end, ATP is then hydrolyzed to ADP and Pi, Pi is lost, and ADP-actin dissociates from the (−) end.

D. ATP–G-actin is added much faster at the (-) end than at the (+) end, resulting in a lower critical concentration at the (-) end than at the (+) end.

E. At steady state, actin subunits treadmill through a filament. ATP-actin is added at the (-) end, ATP is then hydrolyzed to ADP and Pi, Pi is lost, and ADP-actin dissociates from the (+) end.

Which of the following statements are correct?

#Question id: 10907

#Unit 6. System Physiology – Plant

The mechanism of phloem translocation in angiosperms is best explained by the pressure-flow model, this model is an example of,

#Question id: 10908

#Unit 6. System Physiology – Plant

The energy is necessary to move photosynthate from producing cells into the sieve elements. This movement of photosynthate is called

#Question id: 10909

#Unit 6. System Physiology – Plant

The energy is essential for some aspects of movement from sieve elements to sink cells, which store or metabolize the sugar. This movement of photosynthate from sieve elements to sink cells is called

#Question id: 10910

#Unit 6. System Physiology – Plant

In early research on phloem translocation, both active and passive mechanisms were considered. All theories, both active and passive, assume an energy requirement in both sources and sinks. What will be the INCORRECT explanation of active and passive mechanism?

#Question id: 10911

#Unit 6. System Physiology – Plant

Researchers have investigated bidirectional transport by applying two different radiotracers to two source leaves, one above the other. Researcher wanted to see how bidirectional transport happens in sieve elements. Which one of the following is INCORRECT interpretation for bidirectional transport?

#Question id: 10912

#Unit 6. System Physiology – Plant

Velocities for transport in the phloem are measured by using a technique which detect water flow;