Plants show mitotic divisions in
Mitosis is the type of cell division that ensures equal distribution of genetic material in daughter cells. Mitosis can occur both in diploid and haploid cells. The main function of mitosis is to make copies of cells for growth and regeneration. If a haploid cell undergoes mitosis, which is something certain types of plant and fungus do as part of their normal life cycles, the end result is two identical haploid cells (n→n), Some plants and fungi have their bodies composed of haploid cell .
Plant Cytokinesis differ from animals Cytokinesis in having
In plants, cytokinesis or division of cytoplasm occurs due to formation of cell plate but in animals cytokinesis occurs due to formation of constriction in the middle cell membrane.
Cell growth results in disturbing the ratio between
Cell growth results in disturbing the ratio between the nucleus and the cytoplasm. It therefore becomes essential for the cell to divide to restore the nucleo-cytoplasmic ratio.
Chromosome appeared beaded during
Chromosome appeared beaded during leptotene stage of prophase of meiosis I of meiosis cell division. Chromatin materials start condensing after that stage.
The transition period between M- phase I and M- phase II in without DNA replication
The transition period between M-phase of Meiosis I and M-phase II during which no replication of DNA occurs is called as interkinesis.
What is the average cell cycle span for a mammalian cell?
The average cell cycle span for a mammalian cell is approximately 24 hours.
Various phases of cell cycle are controlled by proteins
Cycline and CDKs enzymes are involved in controlling various phases of cell cycle.CDKs can modify various protein substrates involved in cell cycle progression.
In some lower plants and social insects, the haploid cells are divided by
In some lower plants and in some social insects haploid cells also divide by mitosis.
During which stage of prophase I the crossing over takes place?
Pachytene: During the third substage of meiosis, the chromosomes continue to condense. Crossing over takes place at this stage and at each point of crossing over a chiasma is formed (singular: chiasma) between non-sister chromatids of homologous chromosomes.
Crossing over results the exchange of genetic material, which occurs between
Crossing over results the exchange of genetic material between to homologous chromosomes during meiosis I of cell division
The number of chromosome and the amount of DNA are changed in
S phase marks the period during which DNA synthesis or replication takes place. During this time the amount of DNA per cell doubles.After metaphase is complete, the cell enters anaphase. During anaphase, the microtubules attached to the kinetochores contract, which pulls the sister chromatids apart and toward opposite poles of the cell
Which phase is called an invisible phase?
S Phase because in this phase chromosomes replicated are divided in such a way as to ensure that each daughter cell receives a copy of every chromosome.
M- phase in mitosis undergoes which type of division?
Since, in mitosis the number of chromosomes in the parent and progeny cells is the same, it is also called as equational division.
Which phase of meiosis in animal cell is shown in figure given below?
The figure given above shows diakenisis phase of prophase of meiosis I as terminalisation of chismata is visualized in it.
Who stated first of all that new cells are formed from division of pre-existing cells?
Rudolf Virchow was the first scientist who stated that new cells are formed from division of pre-existing cells.
In yeast the cell cycle is progressed through
Yeast can progress through the cell cycle in only about 90 minutes.
Multinucleate condition arise when Cytokinesis does not follow karyokinesis, this type of cells are called as
Coenocyte is a multinucleate mass of protoplasm which is formed as a result of repeated nuclear division which is not accompanied by the cell fission, whereas the Syncytium is the multinucleated cell which is formed by the fusion of the multiple unicellular cell.
In plant cells, the new cell wall begins by the
In plant cells, wall formation starts in the centre of the cell and grows outward to meet the existing lateral walls. The formation of the new cell wall begins with the formation of a simple precursor, called the cell plate.
Crossing over results in the exchange of genetic material, which occurs between:
Crossing over is the exchange of genetic material between two homologous chromosomes.
Two similar chromosomes of each type present in diploid cell are called as
Homologous chromosome are two similar chromosome of each type present in diploid cells. During meiosis homologous chromosomes separate from each other.
M phase represents
The M Phase represents the phase when the actual cell division or mitosis occurs
The mechanism of distributing centriole pairs to the daughter cells is called
The mechanism of distributing chromosome by centriole pairs to the daughter cells is called astral division. This kind of division occurs in animal cells.
In between two walls of adjacent cells are seen
The middle lamella serves as a cementing layer between the primary walls of adjacent cells. The primary wall is the cellulose-containing layer laid down by cells that are dividing and growing. To allow for cell wall expansion during growth, primary walls are thinner and less rigid.
The sexual reproduction involves fusion of special type of cell called gametes, produced by
Meiosis cell division is involved in gametes formation as gametes contain half the numbers of chromosome a normal cell diploid cell contain. Gametes fuse to produce zygote.
Astral body are formed of
Astral body are formed of microtubules. Astral bodies are produced by centriole during cell division and attach with centromere of the chromosome.