In mouth cavity of many molluscs there is a rasping tongue like structure_________provided with many horny teeth.
(A) Ligule
(B) Radula
(C) Mantle
(D) Muscle
It is stiff rod of special cells surrounded by connecive tissue present in the mid -dorsal region and appears in the embryos of all chordates
(A) Placenta
(B) Notochord
(C) Cranianta
(D) Ligule
The phylum chrordata comprise about how many species?
(A) 25,000
(B) 50,000
(C) 100,000
(D) 10,00,000
They are considered to be the most primitive and are surely the first of the vertebrates?
(A) Frogs
(B) Reptiles
(C) Amphibinas
(D) Jawless fishes
Scolidon or dog fish belong to the group of fishes called__________?
(A) Cartilaginous fishes
(B) Bony fishes
(C) Running fishes
(D) Jawless fishes
Nephrostome in earthworm opens in____________?
(A) External space
(B) Internal Body cavity
(C) In gut
(D) In Bladder
The nephridia of earthworm open into the coelom by_________?
(A) Nephrostome
(B) Nephridiopore
(C) Flame cell
(D) Anus
Which one of the following is representing the group of diatoms?
(A) Pinnularia, Navicula, Cymbella, Melosira
(B) Euglenamorpha, Hedneria , Heteronema, Colacium
(C) Nostoc, Anabaena, Aulosira, Cylindrospermum
(D) Cochlodinium, Gymnodinium, Lenodinium, Peridinium