Ctenophores generally exhibit
bilateral symmetry
radial symmetry
asymmetry
spherical symmetry
Correct Answer :
A. bilateral symmetry
Related Questions
In Hydra, buds always arise at
the hypostome
the junction of hypostome and stomach
in junction of stomach and stalk
the stomach
Hydra prevents self fertilization by being
protogynous
hermaphrodite
monoecious
protandrous
The small green alga that lives inside Hydra is called
Zoochlorella
Chlamydomonas
Euglena
None of these
In Hydra, the nematocysts are abundant on
upper part
middle part
tentacles
lower part
Cindom is a
battery of nematocysts
group of nematocysts
armed thread
none of these
The mouth opens into a large single cavity in Hydra
coelom
enterocoel
pseudocoel
coelenteron
Hydra reproduces by gemmation (budding) when
Plenty of food is present
Pond dries up
Water becomes muddy
Hydra is alone
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
Enteron is divided by mesentries in
Aurelia
Sea anemone
Obelia
Hydra
Polymorphic coelentrates are the members of the class
hydrozoa
scyphozoa
actinozoa
all of these
Which one is found in Hydra
Metabolism
Metamerism
Melting
Metamorphosis
The body wall of Hydra consists of
ecotderm and endoderm
ectoderm and mesoderm
ectoderm, mesoderm and endoderm
epidermis, mesoglea and endoderm
A coelentrate, commonly known as fresh water polyp is
Hydra
Obelia
Physalia
Acerelia
Strobilization is the characteristic feature of
Aurelia
Hydra
Metridium
Physalia
Among coelenterates medusoid individuals are absent in members of the class
hydrozoa
scyphozoa
anthozoa
all the three
Ephyra is the larval form of
Sea anemone
Aurelia
Obelia
Hydra
Division of labour on morphological basis is well exemplified by
Hydra
Obelia
Monkey
Elephant
What is common between Hydra and Obelia ?
Both show polymorphism
Both possess a larval stage in their life history called planula
Both are found in fresh water
Both havb a jelly like mesoglea with no cells
The testes of hydra are located
below the ovaries
below the tentacles
further down the tentacles to occupy central position of the body
anywhere on the body between tentacles and adhesive disc
Coral reef formation is mainly related to
sponges
anthozoans
molluscs
hydrozoans
Body wall of coelentrates is described as
diploblastic
integument
multicellular
triploblastic
If nematocysts are absent in Hydra, which is affected
Locomotion
Predation
Both (a) and (b)
Reproduction
Coelenteron in Hydra serves the purpose of
digestion and circulation
digestion and storage
excretion and digestion
circulation and storage
Nutritionally Hydra is
saprozoic
herbivorous
insectivorous
carnivorous
Polymorphism is found in
Hydra
Aleyonium
Aurelia
Physalia
The mesoglea of Hydra contains
nerve cells
sensory cells
muscle fibres
no cells
Nematocysts of Hydra are important for
cataching prey
paralysing prey
testing the food
testing the water
The nematocysts develop from
musculo-epithelial cells
interstitial cells
digestive cells
nerve cell
Nematocytes are the specialised cells found in the members of the phylum
porifera
coelentrata
annelida
platyhelminthes
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)