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The chromosomes contain gene which carry specific features to the offsprings.

Replacement of dead cells is accomplished by Mitosis process.

Prophase the largest phase of a normal cell cycle.

The kind of division normally seen at the tip of root and shoot system is Mitosis.

1. Genes are located on chromosomes at specific distance and position. 

2. The greater this distance, the greater the chance that a crossover can occur between the genes and the greater the chances of recombination. 

3. The chances of recombination are less between the genes that are placed closed to each other on the chromosome. 

4. Therefore, due to recombination the two genes located on the same chromosome have possibility of separating from each other.

1. Meiosis ensures that organisms produced by sexual reproduction contain correct number of chromosomes. 

2. Meiosis exhibits genetic variation by the process of recombination. 

3. Variations increase further after union of gametes during fertilization creating offspring with unique characteristics. Thus, it creates diversity of life and is responsible for evolution.

The kind of division takes place in the reproductive tissues Meiosis.

Result of uncontrolled cell division Cancer.

1. Paramoecium is a unicellular organism. The division in Paramoecium occurs by amitosis. 

2. It is the simplest mode of cell division. 

3. In amitosis, nucleus elongates and a constriction appears. This constriction deepens and divides the nucleus in two daughter nuclei followed by the division of cytoplasm.

The process responsible for variation is Crossing -over.

Prophase in mitosis when the nucleolus start disappearing. 

Answer is Prophase

Cytokinesis the process of cytoplasmic division.

The correct answer is (A) telophase

Meiosis gametes are produced.

The number of chromosomes in sex cell is halved.

Histone proteins are synthesized during S – phase

(c) Daughter nuclei are formed at metaphase.

The period between two successive mitotic divisions is Interphase.

(a) yy + xx chromosome 

(b) Metaphase

Anaphase the stage when sister chromosomes separate from their paired condition.

Metaphase II  phase.

The period between two successive mitotic division Interphase.

Karyokinesis Division of nucleus.

Anaphase the shortest phase of mitosis. 

Gamete formation

1. The type of cell division that occurs in apical meristem of plants is Mitosis.

2. Karyokinesis means splitting of nucleus.

3. The stage between Meiosis-I and Meiosis -II is called Interkinesis.

4. Colchicine arrests cell division at Metaphase.

5. Centromere is the point at which sister chromatids are held together.

Centromere two sister chromatids are held together.

Separation of sister chromatids takes place in Anaphase. 

Interkinesis

Telophase I usually skipped in meiosis.

Anaphase I  stage.

Zygotene is sydapsis in chromosomes to form bivalents.

Crossing over occurs during this jsubstage of meiosis in Prophase I.

Pachytene stage.

Chromatids: Two identical parts of a chromosome called “sister” chromatids.

Cell division: Process by which a cell divides into two new daughter cells.

Diakinesis: In this stage nuclear membrane and nucleolus disappear. Spindle begins to be formed at the end of this stage.

The process of meiosis takes place to produce Sperms and ova. 

Diplotene: Crossing-over continues and two homologous chr omosomes in each pair begin to separate. They are held together at chiasmata.

Leptotene, Zygotene and Diplotene phases are found in Prophase of Meiosis-I.

Pachytene: The crossing-over begins at the end of this stage.

Zygotene: Pairing of homologous chromosomes (synapsis) occur in this stage. Each pair is a bivalent.

Leptotene: This step the chromosomes become visible as single threads.

1. Meiotic division produces gametes or spores. 

2. If it is absent, the number of chromosomes would double or quadruple resulting in the formation of monstrosities (abnormal gametes). 

3. The constant number of chromosomes in a given species across generations is maintained by meiosis and fertilization. 

4. Because of crossing over, exchange of genetic material takes place leading to genetic variations, which are the raw materials for evolution.

Crossing over: 

The process of exchange of genetic material between non-sister chromatids of homologous chromosomes is known as crossing over.

Significance of crossing over: 

Crossing over results in genetic recombination of parental characters that leads to variations.

The correct answer is (C) new gene combination

Mitosis is called equational division because during mitosis the cell divides equally into two identical daughter cells.

Metaphase: 

a. Chromosomes are completely condensed and appear short. 

b. Centromere and sister chromatids become very prominent. 

c. All the chromosomes are arranged at equatorial plane of cell. This is called metaphase plate. 

d. Mitotic spindle is fully formed in this phase. 

e. Centromere of each chromosome divides horizontally into two, each being associated with a chromatid. 

[Note: The centromeres divide at the beginning of anaphase so that the two chromatids of each chromosome become separated from each other. 

Source: Cell Division, Donald B. McMillan, Richard J. Harris, in An Atlas of Comparative Vertebrate Histology, 2018.]