(a) Explain why budding, fragmentation and regeneration are considered the sexual mode of reproduction? 

(b) Describe the regeneration process in planaria using clear diagrams. 

(a) Budding, fragmentation and regeneration are all considered Asexual modes of reproduction because these methods involve only one parent. Asexual reproduction is a kind of reproduction by which offspring arise from a single organism (single parent) and inherit the genes of that parent only. Thus The offspring will be exact genetic copies of the parent. 

Budding is a type of asexual reproduction in which a new organism develops from an outgrowth or bud. 

Fragmentation is also a type of asexual reproduction in which an organism is split into two. 

(b) Regeneration is again a type of asexual reproduction in which organisms can be regenerated from a single parent. 

Regeneration is a form of asexual reproduction. It is the tendency of a simple organism to re-grow its lost parts. Planaria can be cut into the desired number of pieces, and each piece grows through specialized cells into a complete organism.