Colchicine, a microtubule depolymerizing drug, is expected to be:
Mitosis inhibition but allow cytokinesis
Inhibit cytokinesis
Allow mitosis beyond metaphase
induce formation of multiple contractile rings
Microtubules, the third major component of the cytoskeleton, are rigid, hollow rods with a diameter of around 25 nm.
Microtubules, like actin filaments, are dynamic structures that constantly build and disintegrate within the cell.
They have a role in a variety of cell motions, including various types of cell motility, intracellular organelle movement, and chromosome division during mitosis, in addition to defining cell shape.
Microtubules are made up of globular proteins, specifically tubulin.
Tubulin is a dimer composed of the 55-kD polypeptides -tubulin and -tubulin that are securely linked together.
Like actin, - and -tubulin are encoded by small clusters of related genes.
A third type of tubulin, known as -tubulin, is also found at the centrosome and is required for the start of microtubule assembly.
Colchicine, a microtubule depolymerizing medication, is believed to prevent spindle formation during mitosis, allowing mitosis to progress beyond metaphase and encourage the creation of numerous contractile rings.
The autumn crocus, Colchicum autummale, contains an alkaloid called colchicine.
It inhibits the formation of spindles during mitosis, preventing chromosomes from separating during anaphase and resulting in the generation of several sets of chromosomes. This has no effect on cytokinesis.
Hence, option 1 is the correct answer.