The type of reproduction where two reproductive cells join to form one cell that grows into a new organism is called sexual reproduction.

Here's why:

* Two reproductive cells: This refers to the fusion of a sperm cell (male gamete) and an egg cell (female gamete).

* Form one cell: The fusion of the sperm and egg creates a single cell called a zygote.

* Grow into a new organism: The zygote undergoes cell division and development to form a complete new organism.

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