Question

How is mitosis in plant cells different from mitosis in animal cells?

Answer 1

Plant and animal cells both undergo mitotic cell divisions. Their main difference is how they form the daughter cells during cytokinesis. During that stage, animal cells form furrow or cleavage that gives way to formation of daughter cells. Due to the existence of the rigid cell wall, plant cells don't form furrows.

Answer 2

Unlike animal cells, mitosis in plant cells occurs without centrioles and cytokinesis is centrifugal.

Step-by-step explanation:

In the mitosis of superior plant cells, basically two differences can be highlighted, in comparison with what occurs in the mitosis of the animal cell:

• Mitosis occurs without centrioles: From certain places, corresponding to the centrosomes, the spindle fibers are irradiated. Since there are no centrioles, then there is no aster. For this reason, it is said that mitosis in plant cells is anastral (from Greek, an = negative);
• Cytokinesis is centrifugal: it occurs from the center to the periphery of the cell. At the beginning of the telophase, fragmoplasm is formed, a set of protein microtubules similar to those of the dividing spindle. The fragmoplast microtubules function as scaffolding that guide the deposition of a disc-like median cellular plaque, originating from fused vesicles of the Golgi system. Progressively, the cellular plaque grows towards the periphery and, at the same time, inside the vesicle, deposition of some substances occurs, among them, pectin and hemicellulose, both polysaccharides. On each side of the cell plate, the fused membranes contribute to the formation, in that region, of the plasma membranes of the two new cells, which end up connecting with the plasma membrane of the mother cell. In continuation of the formation of this median lamella, each daughter cell deposits a primary cellulosic wall, outside the plasma membrane. The primary wall ends up extending across the perimeter of the cell. At the same time, the primary cellulosic wall of the mother cell is progressively dismantled, which allows the growth of each daughter cell, each of which now has a new primary wall. So, if we could look at this median region of one of the cells, from the cytoplasm outwards, we would see, initially, the plasma membrane, then the primary cellulosic wall and then the middle lamella. Eventually, a secondary wall may be deposited between the plasma membrane and the primary wall.