Following statements are regarding to Kinetochore-microtubule interaction in S. cerevisiae.

A. In the simple kinetochore of S. cerevisiae, a protein complex called CBF3 associates with specialized, centromere-specific form of histone H3, called CENP-A.

B. The Ndc80 complexes initially make lateral interactions with a spindle microtubule and subsequently interact with a Dam1 complex, which forms a ring around the end of the microtubule. This interaction results in an end-on attachment of the centromere to the

spindle microtubule.

C. Microtubules that “capture” kinetochores are selectively stabilized by a reduction in the rate of catastrophes, which increases the chance that the attachment will persist.

D. With the two kinetochores attached to opposite poles, the duplicated chromosome is now under tension, being pulled in both directions by the one sets of kinetochore microtubules.

Which of the following combinations is correct?

#Question id: 11736

#Unit 6. System Physiology – Plant

Many plant tissues contain the enzyme cytokinin oxidase, which cleaves the side chain, except

#Question id: 11737

#Unit 6. System Physiology – Plant

Cytokinins have been shown to have effects on many physiological and developmental processes, including____

a) Leaf senescence

b) Apical dominance

c) Gametophytic  development

d) Vascular development

e) Breaking of bud dormancy

f) Causing bud dormancy

#Question id: 11738

#Unit 6. System Physiology – Plant

The ribotide and riboside forms of trans-zeatin can be interconverted, and free trans-zeatin can be formed from the ribotide by the

#Question id: 11739

#Unit 6. System Physiology – Plant

which of the following compound is resist to cleave by cytokinin oxidase and why?

#Question id: 11740

#Unit 6. System Physiology – Plant

Some given characteristics of the two types of sieve elements in seed plants such as Sieve tube elements and Sieve cells. Find out the  true characteristics of sieve tube elements from the given statements;

i) Found in angiosperms

ii) Sieve plate pores are open channels

iii) Albuminous cells sometimes function as companion cells

iv) P-protein is present in all eudicots and many monocots

v) There are no sieve plates; all sieve areas are similar

#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?