Question

1) An organism is described as 2n = 30.

How many chromosomes are in one meiotic cell during prophase 2?

2) An organism is described as 2n = 30.

How many chromatids per chromosome are in one meiotic cell during Anaphase 1?

3) An organism is described as 2n = 30.

How many chromosomes are in one meiotic cell during metaphase 1?

4) An organism is described as 2n = 30.

How many chromosomes are in one cell during G₁ of interphase?

Answer 1

1) 2n= 30 means the organism has 30 chromosomes in the cell.During the meiosis division the chromosome number gets reduced to half in meiosis 1.After meiosis 1 there will be 15 chromosomes in each cell.In meiosis 2 the number of chromosomes remains same.So during prophase 2 the number of chromosomes will be same (15) in the cell.

2) During anaphase 1 in meiosis the chromatids does not separate and whole chromosome moves toward its respective pole.So each chromosome possess 2 chromatids during Anaphase 1.

3)When a cell has 30 chromosomes during its 2n phase the number of chromosomes remain same during metaphase 1 as the chromosomes are located/situated on equatorial plate.They have not separated yet.Separation takes place during anaphase 1.So the number of chromosomes remains 30 in the cell.

3)In the G1 or Gap 1 phase the cell becomes ready for division which is either mitotic or meiotic.Cell synthesizes m RNA and essential proteins.So the number of chromosomes remain same (30).