In the case of Poriferans, the spongocoel is lined with flagellated cells called:
1. Oscula
2. Choanocytes
3. Mesenchymal cells
4. Ostia
A jawless fish, which lays eggs in freshwater and whose ammocoetes larvae after metamorphosis return to the ocean is?
1. Eptratretus
2. Myxine
3. Neomyxine
4. Petromyzon
Metagenesis refers to?
1. | The presence of different morphic forms |
2. | Alternation of generation between asexual and sexual phases of an organism |
3. | Occurrence of a drastic change in the form during post-embryonic development |
4. | Presence of a segmented body and parthenogenic mode of reproduction |
Planaria possess a high capacity of:
1. metamorphosis
2. regeneration
3. alternation of generation
4. bioluminescence
A marine cartilaginous fish that can produce electric current is:
1. Pristis
2. Torpedo
3. Trygon
4. Scoliodon
One example of animals having a single opening to the outside that serves both as mouth as well as the anus is:
1. Octopus
2. Asterias
3. Ascidia
4. Fasciola