what is the most important stage of mitosis? explain.?

Question

tnx

Answer 1

Mitosis is the process by which a cell separates its duplicated genome into two identical halves.

The mitotic phase is a relatively short action-packed period of the cell cycle.


Prophase

Normally, the genetic material in the nucleus is in a loosely bundled coil called chromatin. At the onset of prophase, chromatin condenses together into a highly ordered structure called a chromosome.


Prometaphase

The nuclear envelope dissolves and microtubules invade the nuclear space. This is called open mitosis, and it occurs in most multicellular organisms.


Metaphase

As microtubules find and attach to kinetochores in prometaphase, the centromeres of the chromosomes convene along the metaphase plate or equatorial plane, an imaginary line that is equidistant from the two centrosome poles.


Anaphase

When every kinetochore is attached to a cluster of microtubules and the chromosomes have lined up along the metaphase plate, the cell proceeds to anaphase.

Two events then occur; First, the proteins that bind sister chromatids together are cleaved, allowing them to separate. These sister chromatids turned sister chromosomes are pulled apart by shortening kinetochore microtubules and toward the respective centrosomes to which they are attached. Next, the nonkinetochore microtubules elongate, pushing the centrosomes (and the set of chromosomes to which they are attached) apart to opposite ends of the cell.

These two stages are sometimes called early and late anaphase. At the end of anaphase, the cell has succeeded in separating identical copies of the genetic material into two distinct populations.



Telophase

Telophase is a reversal of prophase and prometaphase events. It "cleans up" the aftereffects of mitosis.


Cytokinesis

Often (mistakenly) thought to be the same process as telophase, cytokinesis, if it is to occur, is usually well under way by this time. In animal cells, a cleavage furrow containing a contractile ring develops where the metaphase plate used to be, pinching off the separated nuclei.

Answer 2

The evolutionary progression didn’t contain bacteria with wombs. the consumer-friendly progression in the lineage maximum suitable to us could be some thing like: Bacterium: Reproduce via splitting. single-celled protist: Reproduce via splitting. Colonial protist: Reproduce via splitting or via forming gametes that waft off in the water and fertilize one yet another. Hermaphroditic. Small multicelled animal – probable early sponge or placozoan: reproduce via splitting or via forming gametes that waft off in the water and fertilize one yet another. Hermaphroditic. Wormlike animal: Reproduce via forming gametes that fertilize one yet another close to the physique. probable hermaphroditic. Lancelet-like animal w primitive notochord: Reproduce making use of gametes and close to-physique fertilization. 2 sexes (women produce greater gametes). Jawless fish: comparable duplicate as lancelet. Jawed fish: comparable duplicate. Fish-like amphibian which includes acanthostega: comparable duplicate. Early reptile: inner fertilization making use of cloaca; water-resistant eggshell. countless mammal-like reptiles: comparable duplicate. Early monotreme mammal: comparable duplicate yet with milk production. Early marsupial mammal: inner fertilization making use of differing woman and male organs, observed via inner gestation, early beginning, and progression in pouch. Milk production. Early placental mammal: inner fertilization making use of diverse woman and male organs, observed via inner gestation in placenta, and later beginning. Milk production.