What is meant by isogamy?

Isogamy:

1. Isogamy is a form of sexual reproduction, which involves the fusion of morphologically similar gametes, having similar shapes and sizes.
2. Isogamy is commonly found in Chlamydomonas.
3. Isogamous organisms have two different mating types “+” and “-”.
4. Some isogamous species have more than two mating types, but the number is usually lower than ten.
5. In some extremely rare cases, a species can have thousands of mating types.
6. In all cases, fertilization occurs when gametes of two different mating types fuse to form a zygote.