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Triploids and Diploids (GCSE)

Matthew Griffy

Why can’t they reproduce?

What’s a Diploid?

Reply 1

Matthew Griffy

Why can’t *Triploids* reproduce?

Reply 2

Ambitious1999

Original post by Matthew Griffy

Why can’t they reproduce?

What’s a Diploid?

Diploid, Triploid, haploid etc refer to the numbers of copies of chromosomes in cells.

Diploid
In normal circumstances Normal cells have two copies of each chromosome, for instance skin cells, white blood cells etc. Or leaf cells in plants. They all have a pair of each chromosome. Hence “Di”-ploid.
In total humans normally have 46 chromosomes in each cell except for sperm or ova cells. Diploid cells can not sexually reproduce.

Haploid
Sex cells (Gametes) such as Sperm or Ova however only have ONE copy of each chromosome they are Haploid. Meaning they only have half the number of chromosomes. These can sexually reproduce.
So human sperm or ova cells only have 23 chromosomes.

Why can’t diploid cells reproduce?
Because you would end up with twice the normal amount of chromosomes that would be 4 copies of each chromosome! The number of chromosomes needs to be halved before fertilisation.
To reproduce the Haploid sperm cell fertilises the haploid ova cell resulting in a diploid cell that divides and differentiates into an embryo.

Haploid cells originate from diploid cells by the process of Meiosis where the number of chromosomes is reduced by half.

Triploids.
These have 3 copies of each chromosome. Again for the same reasons as diploids they can not reproduce.
You need a haploid number of chromosomes for sexual reproduction.

Hope that helps. Good luck :smile: