MEIOSIS
Difference between Haploid and Diploid, and Human Karyotype
Introduction:
Meiosis is a type of cell division that results into four daughter cells, each with half
number of chromosomes of the parent cell. It is the cell division of a diploid cell (parent
cell) into four haploid cells (daughter cells), which develop to produce gametes. In
animals, it occurs in the female ovary (ova) and male testes (spermatozoa). In plants, it
occurs in the female ovary (ovule) and male anthers (pollen grains).
The structure of chromosome
NB:
• Haploid (half) + Haploid (half) = Diploid (whole)
• Male gamete (sperm) + Female gamete (ova) = Zygote
• Haploid is the quality of a cell or organism having a single set of chromosomes
• Diploid is when a cell or organism has paired or two sets chromosomes, one from
each parent.
• For sexual reproduction to take place, a haploid male gamete will fuse with a haploid
female gamete during fertilization. The result is a diploid zygote.
Un-replicated Replicated • Sex cells (gametes) i.e., sperms and ova are haploid (n), (23 chromosomes in human)
chromosomes chromosomes
• somatic cells (body cells) are diploid (2n), (46 chromosomes / 23 pairs of
chromosomes in human).
Describing the structure chromosome • The 23 pairs of chromosomes that result in a zygote are divided as follows:
- 22 pairs of autosomes
• Chromosomes are thread-like structure
- 1 pair of sex chromosome called gonosomes represented by XX in females
• Each chromosome is made up of proteins and DNA (genes). and XY in males.
• The DNA tightly coiled many times around proteins, that called histone that support
the structure.
The functions of the chromosomes
• It carries genetic information from one generation to another.
• Responsible for gene regulation, protein synthesis and cellular respiration.
Difference between Haploid and Diploid, and Human Karyotype
Introduction:
Meiosis is a type of cell division that results into four daughter cells, each with half
number of chromosomes of the parent cell. It is the cell division of a diploid cell (parent
cell) into four haploid cells (daughter cells), which develop to produce gametes. In
animals, it occurs in the female ovary (ova) and male testes (spermatozoa). In plants, it
occurs in the female ovary (ovule) and male anthers (pollen grains).
The structure of chromosome
NB:
• Haploid (half) + Haploid (half) = Diploid (whole)
• Male gamete (sperm) + Female gamete (ova) = Zygote
• Haploid is the quality of a cell or organism having a single set of chromosomes
• Diploid is when a cell or organism has paired or two sets chromosomes, one from
each parent.
• For sexual reproduction to take place, a haploid male gamete will fuse with a haploid
female gamete during fertilization. The result is a diploid zygote.
Un-replicated Replicated • Sex cells (gametes) i.e., sperms and ova are haploid (n), (23 chromosomes in human)
chromosomes chromosomes
• somatic cells (body cells) are diploid (2n), (46 chromosomes / 23 pairs of
chromosomes in human).
Describing the structure chromosome • The 23 pairs of chromosomes that result in a zygote are divided as follows:
- 22 pairs of autosomes
• Chromosomes are thread-like structure
- 1 pair of sex chromosome called gonosomes represented by XX in females
• Each chromosome is made up of proteins and DNA (genes). and XY in males.
• The DNA tightly coiled many times around proteins, that called histone that support
the structure.
The functions of the chromosomes
• It carries genetic information from one generation to another.
• Responsible for gene regulation, protein synthesis and cellular respiration.
