Kinetochores are disc-shaped structures on chromosomes, which help in the attachment of spindle fibres.

Gene expression, protein synthesis, secretion, motility etc, do not happen during M-phase.

Mitosis is called an equational division because it divides the mother cell into two daughter cell, which are identical to the original mother cell in every respect. In mitosis, the chromosomes of the mother cell are duplicated and distributed equally to the daughter cells and daughter cells have same number of chromosomes as matter cell has.

It happens so because it is physically easier for short and compact chromosomes to move through the cytoplasm than the very long twisted interphase chromosomes.

Karyokinesis is a series of uninterrupted changes before forming two daughter nuclei. Though karyokinesis is a continuous process, it has been divided into four phases. They are prophase metaphase, anaphase and telophase.

Chromosomes seem to be beaded during leptotene(prophase-I) of meiosis.

Meiosis is essential in sexually reproducing organisms because it keeps the chromosomes number constant.

Calculation of number of mitosis
Mitosis of one cell produces 2 cells. Similarly, 2 cells undergoing mitosis give rise to 4 cells and so on.
This can be generalised as:
2ⁿ = number of daughter cells, where n = number of cycles of mitotic cell division.
Since the tissue has 1024 cells
⇒ 1024 = 210 cycles
Hence, the original parental single cell has undergone 10 cycles of mitosis to give rise to 1024 cells.
Ten cycles of mitosis.

Cytokinesis is the division of cytoplasm, whereas karyokinesis is the division of nucleus of the cell.

DNA replication occurs in the nucleus whereas centriole duplication takes place in the cytoplasm.

Mitosis helps in regeneration by keeping all the somatic cells of an organism genetically similar, so that they are able to regenerate part or whole of the organism.

significance of meiosis :
1. Meiosis is responsible for the formation of sex cells or gametes that are responsible for sexual reproduction.
2. It activates the genetic information for the development of sex cells and deactivates the sporophytic information.
3. It maintains the constant number of chromosomes by halving the same. This is important because the chromosome number doubles after fertilization.
4.In this process independent assortment of maternal and paternal chromosomes takes place. Thus the chromosomes and the traits controlled by them are reshuffled.
5. The genetic mutation occurs due to irregularities in cell division by meiosis. The mutations that are beneficial are carried on by natural selection.
6. Crossing over produces a new combination of traits and variations.

Yes, mitosis can occur before or after the interphase, as dividing phase (meiosis or mitosis) and interphase is the only major phase of a cell cycle.

The average cell cycle span for a mammalian cell is approximately 24 hours.

Colchicine is a mitotic inhibitor, so it inhibits the M phase or mitotic phase.

There are two distinct type of cell divisions taking place in multicellular organisms One is mitosis in somatic cells for growth and healing of wounds and the other is meiosis in reproductive cells for producing gametes having half the number of chromosomes. It is essential to maintain the characters of the species.
More number of cells are produced in meiosis. Each division of mitosis results in the formation of two cells while in meiosis four cells are formed.

All these happen in the two haploid nuclei simultaneously.
(i) Prophase-II, takes short time. Spindle formation begins and the chromosomes become short. Two chromatids are joined to a single centromere. Nuclear membrane and nucleous disintegrate.
(ii) Metaphase-II At the equator, the chromosomes align at the equator and spindle is formed. The centromere of every chromosome is joined to the spindle fibre and centromere also divides.
(iii) Anaphase-II The daughter chromosomes are formed. Chromatids move towards their poles with the spindle fibres.
(iv) Telophase-II Reaching at the poles, chromosomes form nuclei which are haploid(n) daughter nuclei. Again nuclear membrane is constructed. Nucleous now becomes clearly visible.
Cytokinesis Occurs and four daughter cells are formed which are haploid (n). It may occur once or twice or only after the meiosis-II cell division.

Cell division is significant in the following ways
(i) Cell multiplication Cell division is a means of cell multiplication or formation of new cells from pre-existing cells.
(ii) Continuity It maintains continuity of living matter generation after generation.
(iii) Multicellular organisms The body of a multicellular organism is formed of innumerable cells. They are formed by repeated divisions of a single cell or zygote. As the number of cells increases, many of them begin to differentiate, form tissues and organisms.
(iv) Cell size Cell division helps in maintenance of a particular cell size which is essential for efficiency and control of cell activities.
(v) Genetic similarity The common type of cell division or mitosis maintains genetic similarity of all the cells in an individual despite being different, i.e., structurally and functionally.

(i) X-Miltosis      
Y-Meiosis
(ii) (a) In X, there is no association of homologous chromosomes, but in Y, homologous chromosomes pair up together to form bivalents during prophase-I.
(b) In X, there is no crossing over as there is no formation of chiasmata, but in Y, crossing over occurs at the chiasmata whereby some genes are swapped between homologous chromosomes.

Cell division id the first stage of growth in living organisms whereby cells divide to form new cells.
(i) In unicellular organisms, cell division is a process of asexual reproduction. It leads to an increase in the total number individuals.
(ii) In multicellular organism, the division of all cells, other than the reproductive cells is known as mitosis. It is a process of cell division related to growth and is accomplished by the cellular enlargement and differentiation.

cell division, cell reproduction or cell multiplication is the process of formation of new daughter cells from the pre-existing cell or parent cell.
It is three types
(i) Amitosis
(ii) Mitosis
(iii) Meiosis.
A cell divides when it attains the size and the nucleocytoplasmic ratio disturbs. The DNA duplication also causes a cell to divide.

Chiasmata is X-shaped structure of separated bivalents of recombined homologous chromosomes. Chiasmata formation is necessary for the separation of homologous chromosomes which have undergone the process of crossing over.

The cells found arrested in diplotene stage for months and years are oocyte cells of vertebrates such as tailed and tailless amphibians, birds and insects.
The chromosomes of these cells transform into the Lampbrush form during the diplotene stage of meiotic prophase due to an active transcription of many genes. These chromosomes produce large amounts of RNA for the oocyte and most of the genes present in the DNA loops are being expressed actively.