The body wall of Hydra consists of
ecotderm and endoderm
ectoderm and mesoderm
ectoderm, mesoderm and endoderm
epidermis, mesoglea and endoderm
Correct Answer :
B. ectoderm and mesoderm
Related Questions
Which of the following animals has a nervous system but no brain ?
Earthworm
Hydra
Amoeba
Cockroach
The poisonous fluid present in the nematocysts of Hydra is
toxin
venom
hypnotoxin
haematin
Ephyra is the larval form of
Sea anemone
Aurelia
Obelia
Hydra
Hydra prevents self fertilization by being
protogynous
hermaphrodite
monoecious
protandrous
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
Nutritionally Hydra is
saprozoic
herbivorous
insectivorous
carnivorous
A chitinous material is present in the
coenosarc of Obelia
perisarc of Obelia
body wall of Sea anemone
umbrella of Aurelia
Six septa or six mesenteries are characteristic of
Aurelia
Sea anemone
Obelia
Hydra
Hydra has no special structure for
attachment
respiration
food capturing
offense
In Hydra, the physiological division of labour is exhibited by
cellular layers
tissues
cell differentiation
organs
Ctenophores differ form cnidorians in one important aspect, that is
absence of musculoepithelial cells in the body wall
absence of nematocysts
absence of sensory cells
absence of sexual reproduction
The body of Hydra is
asymmetrical
bilaterally symmetrical
radially symmetrical
irregular
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
Tentacles of Hydra help in
locomotion
food capturing
locomotion and food capturing
respiration
The first invertebrates to develop a true nervous system are
sponges
coelenterates
annelids
arthropods
The scientific name of organ pipe coral is
Tubipora
Astrangia
Meandra
Aeropora
The flagella of food-absorbing cells in hydra aid in
stirring up the digestive fluid in the digestive cavity
engulfing food particles
engulfing semi-digested particles inside food- absorbing cells
none of these
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
Among coelenterates medusoid individuals are absent in members of the class
hydrozoa
scyphozoa
anthozoa
all the three
A Hydra usually possess
single testis and many ovaries
single ovary and many testes
one testis and one ovary
many testes and many ovaries
The mesoglea of Hydra contains
nerve cells
sensory cells
muscle fibres
no cells
Enteron is divided by mesentries in
Aurelia
Sea anemone
Obelia
Hydra
A coelentrate, commonly known as fresh water polyp is
Hydra
Obelia
Physalia
Acerelia
If a Hydra is cut into two pieces, it is noted that
both parts die
both parts make up the loss and form two new individuals
both parts live independently as they are
none of these
In Hydra, buds always arise at
the hypostome
the junction of hypostome and stomach
in junction of stomach and stalk
the stomach
Polymorphic coelentrates are the members of the class
hydrozoa
scyphozoa
actinozoa
all of these
Hydra reproduces by budding when
plenty of food is present
pond is going dry
Hydra is alone
water becomes muddy
Rhopalia are the sense organs in medusa belonging to the class
hydrozoa
scyphozoa
actinozoa
all of these
Hydra respires through
mesoglea
general surface
pellicle
gastrodermis
The mouth opens into a large single cavity in Hydra
coelom
enterocoel
pseudocoel
coelenteron