How many cleavages are completed in 16 cell stages of frog's egg ?
3
8
4
12
Correct Answer :
C. 4
Related Questions
A freshly unfertilised egg of hen contains
one cell
100 cells
1000 cells
10000 cells
Cleidoic eggs are found in
birds
mammals
insects
molluscs
Which of the following do not show parental care over their young ones ?
mammals
lizards
fowls
earwigs
During cleavage, the embryo
enlarges in size
decreases in size
retains the same size at the beginning
gradually enlarges in size
In the human female, the primary oocytes remain small without any growth for
4-5 years
6-8 years
8 - 10 years
12 -14 years
The allantoic vesicle arises from
foregut
midgut
hindgut
somatopleure
Human egg is
centrolecithal
microlecithal
mesolecithal
telolecithal
Constructive change in the development of frog from tadpole is
disappearance of tail
food habit becoming carnivore
land habit
excretion beocmes mesonephric
Antifertilizin is secreted by
fertilized egg
spermatozoa
unfertilized egg
egg membranes
Oogonia entering the growth phase of oogenesis is called
primary oocyte
secodnary oocyte
ootid
gonocyte
During fertilization the spermatozoa penetrate through the egg membranes with the help of
flagellum
acrosome
sperm lysins released from the acrosome
mitochondira located at the middle piece
For fertilization of the frog's egg
sperms of same species are essential
sperms do not need penetration
sperms of any animal can fertilize
only presence of male is sufficient
Laternal line system of sense organs present in the skin of tadpole larva
completely disappears during metamorphosis
partialy retained during metamorphosis
partially disappears during later stages of metamorphosis
fully retained in the adult frog
The sexual embrage of the male and female frogs is called
copulation
amphimixis
syngamy
amplexus
During the development of frog, the ar-chenteron is formed in
early blastula
late blastula
early gastrula
lategastrula
Grey cresent is present in
zygote of frog
brain of rabbit
eye of frog
retina of cockroach
Sexual reproduction in larval condition is known as
paedogamy
autogamy
isogamy
anisogamy
In the growing oocyte, the nucleus enlarges in size due to an increase in
Proteins
Nucleoplasm
DNA
RNA
In frog's egg the divisoin is
holoblastic
meroblastic
diploblastic
triploblastic
Which of the following does not show metamorphosis ?
Frog
Housefly
Hydra
Mosquito
In order to become structurally and functionally a spermatozoan, each spermatid has to undergo a process of differentiation called
spermiation
spermiogenesis
spermatogenesis
androgenesis
The formation, development and matura- j tion of the female gamete is called
ovulation
oogenesis
vitellogenesis
folliculogenesis
Oral contraceptives check
ovulation
fertilization
implantation
entry of sperms into vagina
Mammalian placenta is
a cord between mother and foetus
place of attachment in uterus wall where exchange of material between mother and foetus takes place
outer covering of foetus
allantoic part of the uterus
Embryo sac in a hen's egg is formed by
ectoderm
meso derm
somatic mesoderm and endoderm
splanchnic mesoderm and ectoderm
During metamorphosis, the disappearance of larval organs is called
histogenesis
paedogenesis
histolysis
paedomorphosis
A true coelom is covered by
ectoderm
endoderm
mesoderm
ecto and mesoderm
The process of synthesis of yolk by the oocyte is termed
folliculogenesis
oogenesis
vitellogenesis
spermiogenesis
In frog, gastrulation is completed by
epiboly
emboly
both and
delamination
The sperm produces substances of enzymatic nature of sperm lysin. In mammals, it is called
hyaluronidase
hyaluronic acid
androgamone
cryanogamone