Hydra prevents self fertilization by being
protogynous
hermaphrodite
monoecious
protandrous
Correct Answer :
D. protandrous
Related Questions
In jelly fishes, the adult is always
polypoid
medusoid
polymorphic
hydroid
Six septa or six mesenteries are characteristic of
Aurelia
Sea anemone
Obelia
Hydra
Green Hydra is
Hydra vulgaris
Chlorohydra viridisma
Hydra oligaetis
None of these
The mesoglea of Hydra contains
nerve cells
sensory cells
muscle fibres
no cells
Polymorphism is best defined as the occurrence of
several types of organ-systems in an individual
different kinds of larval forms in the life history of an animal
different functions performed by a single kind of organism
several different types of individuals in a species
Hydra is
marine, radial, symmetrical and diploblastic
fresh water, biradial, symmetrical and triploblastic
fresh water, radial, symmetrical and diploblastic
marine, radial, symmetrical and triploblastic
Cindom is a
battery of nematocysts
group of nematocysts
armed thread
none of these
A coelentrate, commonly known as fresh water polyp is
Hydra
Obelia
Physalia
Acerelia
Strobilization is the characteristic feature of
Aurelia
Hydra
Metridium
Physalia
A piece of Hydra will regenerate into a full Hydra if it contains a part of
epidermis alone
gastrodermis alone
both (a) and (b)
(a), (b) and tentacles
The mesoglea present in Hydra in between epidermis and gastrodermis is
non-cellular and jelly like material
cellular jelly like material containing sensory cells
cellular jelly like material containing nerve cells
both (a) and (c)
Coral reef formation is mainly related to
sponges
anthozoans
molluscs
hydrozoans
Coelenteron in Hydra serves the purpose of
digestion and circulation
digestion and storage
excretion and digestion
circulation and storage
Communication between the enteron and exterior in coelentrates is through
mouth only
mouth and anus
large number of pores in the body wall
both (b) and (c)
Coelenteron of Hydra serves the double purpose of
digestion and circulation
digestion and storage
excretion and locomotion
circulation and storage
The mouth opens into a large single cavity in Hydra
coelom
enterocoel
pseudocoel
coelenteron
A chitinous material is present in the
coenosarc of Obelia
perisarc of Obelia
body wall of Sea anemone
umbrella of Aurelia
Polymorphic coelentrates are the members of the class
hydrozoa
scyphozoa
actinozoa
all of these
In Hydra, the absence of circulatory system is fulfilled by
ectoderm
endoderm
mesoglea
coelenteron
The tentacles of Hydra are
pinnate
hollow
solid
frilled
Polymorphism is found in
Hydra
Aleyonium
Aurelia
Physalia
The scientific name of organ pipe coral is
Tubipora
Astrangia
Meandra
Aeropora
Hydra reproduces by budding when
plenty of food is present
pond is going dry
Hydra is alone
water becomes muddy
Division of labour on morphological basis is well exemplified by
Hydra
Obelia
Monkey
Elephant
Most favourite food of Hydra is
bacteria
water fleas
tadpoles
fishes
Ctenophores generally exhibit
bilateral symmetry
radial symmetry
asymmetry
spherical symmetry
If nematocysts are absent in Hydra, which is affected
Locomotion
Predation
Both (a) and (b)
Reproduction
Rhopalia are the sense organs in medusa belonging to the class
hydrozoa
scyphozoa
actinozoa
all of these
Enteron is divided by mesentries in
Aurelia
Sea anemone
Obelia
Hydra
The body of Hydra is
asymmetrical
bilaterally symmetrical
radially symmetrical
irregular