Give an account of sexuality in organisms.

In organisms, sexual reproduction generally involves the fusion of gametes from two different individuals.
i) Plants may have both male and female reproductive structures in the same plant are called Bisexual plants and on different plants are called Unisexual plants.
ii) In several Fungi and plants, terms such as Homothallic (male and female reproductive organs on the same thallus - Fungi) and Monoecious (presence of both male and female sex organs on the same plant - Plants) are used for bisexual condition.
E.g. Homothallic – Rhizopus sexualis
(Fungus)
Monoecious – Chara, Maize, Cucurbits, Coconut

iii) Heterothallic (Male and female reproductive organs develop on different thalli of same species) and dioecious (male and female sex organs are present on separate plants of same species) are used for unisexual condition.
E.g. Heterothallic – Rhizopus stolonifer
Dioecious– Marchantia, Papaya, Date palm

iv) In flowering plants, the unisexual male flower is called Staminate flower, it contains only stamens. The unisexual female flower is called Pistillate flower, it contains only pistils.
E.g. Papaya