What are the advantages and disadvantages of chasmogamous flowers? 

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Dear Student
Advantages of chasmogamous flowers:

1. Genetically distinct seed due to sexual recombination.
2. Reduced inbreeding depression
3. Seeds produced due to cross pollination show hybrid vigour

Disadvantages are:

1. Availability of pollinating agents determines pollination
2. Generally develop when resources like light, pollinators, water and nutrients are surplus.
3. Flowers need to colourful and more attractive to pollinators thus more resources are utilised and is energetically costly.

Hope this information will clear your doubts about topic.
Regards