Flame cells present in the members of Platyhelminthes are specialized to perform:

In which of the following organisms,self-fertilization is rarely seen?

Assertion $A$: Animals of Phylum $Platyhelminthes$ have an incomplete digestive tract.
Reason $R$: In $Platyhelminthes$,the digestive tract opens to the outside through a single opening.
Which option is correct for Assertion $A$ and Reason $R$?

Which of the following animals is bilaterally symmetrical but acoelomate?

Which of the following organisms possesses an incomplete,branched,and anus-less digestive system?

Turbellarian epidermis differs from that of a trematode due to