3.2 Understand that fertilization involves the fusion of a male and female gamete to produce a zygote that undergoes cell division and develops into an embryo.
The process begins with the adult male (cell in testis) + Adult female (cell in ovary)
These cells have a complete set of chromosomes. This is called being diploid (2n)
For humans it's 46.
These cells divide in the testis to produce a half sets (Gametes). These are know as the sperm cells the the adult male.
This process of cell division is called meiosis.
We got from a diploid to a haploid number (n). This is a half set.
This would be 23 for humans.
In sexual reproduction these cells are brought together and they are joined or fused together, and from a single cell. This is known as fertilization. Combining two half sets of chromosomes to form a full set of chromosomes. eg. 23 + 23 = 46.
This cell is known as a zygote. This is a new cell which is a combination of the male and female chromosomes.
After this mitosis occurs in which the cells will divide.
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