When any plane of section passing through the central axis of body, divides the organism into identical halves, it is called
1. Radial symmetry
2. Biradial symmetry
3. Bilateral symmetry
4. Spherical symmetry
All triploblastic animals primarily possess
1. Bilateral symmetry
2. True coelom
3. Unisexuality with sexual dimorphism
4. Regeneration power
In Planaria, waste material of food digestion and Nitrogenous waste material removed from
1. Mouth and mouth
2. Body wall and body wall
3. Mouth and Flame-cell
4. Mouth and Body wall
Endoskeleton of calcareous ossicles, external fertilization, adults shows radial symmetry, development indirect.
The above-given feature is true for:-
1. Echinus, Asterias
2. Pila, ophiura
3. Antedon, Aplysia
4. Pinctada, cucumaria
Identify the following diagrams and these represent:
1. (a) radial symmetry, (b) bilateral symmetry
2. (a) bilateral symmetry, (b) radial symmetry
3. (a) asymmetrical, (b) radial symmetry
4. (a) bilateral symmetry, (b) asymmetrical
See the following diagrams carefully and these animals are
1. Sycon, Leucosolenia
2. Hydra, Aurelia
3. Nereis, Hirudinaria
4. Fasciola, Taenia
Which of the following option is correct?
1. Fertilization is internal and development is indirect in Scypha, Pleurobrachia
2. Flame cells help in osmoregulation and alimentary canal present in Fasciola, Taenia
3. Body is segmented and perform locomotion with the help of parapordia in Nereis, Pheretima
4. Body is covered by mantle layer and gills are present in Unio, Pila
A true coelom is between
1. Mesoderm and endoderm
2. Ectoderm and mesoderm
3. Body wall and endoderm
4. Body wall and mesoderm
Mark the incorrect statement
1. Radial symmetry is advantageous to sedentary mode of life
2. Notochord is mesodermal in origin placed between dorsal hollow nerve cord and alimentary canal in some animals
3. Pseudocoel (false coelom) derived from blastocoel of the embryo and is bounded by ectoderm and mesoderm
4. Cephalization is the concentration of sense organs, nervous tissue (brain), and food capturing organs at the anterior end
In which of the following Radula is absent ?
1. Sepia
2. Octopus
3. Pila
4. Echinus