The amnion of mammalian embryo is derived from
ectoderm and mesoderm
endoderm and mesoderm
ectoderm and endoderm
mesoderm and trophoblast
A.
ectoderm and mesoderm
The extraembryonic or foetal membranes are amnion, chorion, allantois and Yolk sac.
Amnion is formed from mesoderm on the outer side and ectoderm on the inner side.
Chorion is formed from trophoectoderm and mesoderm whereas allantois and Yolk sac membrane have mesoderm on outer side and endoderm in the inner side.
The contraceptive ‘SAHELI’
blocks estrogen receptors in the uterus, preventing eggs from getting implanted.
increases the concentration of estrogen and prevents ovulation in females.
is a post-coital contraceptive.
is an IUD.
Hormones secreted by the placenta to maintain pregnancy are
hCG, hPL, progestogens, prolactin
hCG, hPL, estrogens, relaxin, oxytocin
hCG, progestogens, estrogens, glucocorticoids
hCG, hPL, progestogens, estrogens
Match the items given in Column I with those in Column II and select the correct option given below :
column (i) | Column (ii) |
(a) Proliferative Phase | (i) Breakdown of endometrial lining |
(b) Secretory Phase | (ii) Follicular Phase |
(c) Menstruation | (iii) Luteal Phase |
a | b | c |
iii | ii | i |
a | b | c |
i | iii | ii |
a | b | c |
iii | i | ii |
a | b | c |
ii | iii | i |
All of the following are part of an operon except
an operator
structural genes
a promoter
an enhancer
A woman has an X-linked condition on one of her X chromosomes. This chromosome can be inherited by
Only daughters
Only sons
Both sons and daughters
Only grandchildren
According to Hugo de Vries, the mechanism of evolution is
Multiple step mutations
Saltation
Minor mutations
Phenotypic variations
AGGTATCGCAT is a sequence from the coding strand of a gene. What will be the corresponding sequence of the transcribed mRNA?
AGGUAUCGCAU
UGGTUTCGCAT
UCCAUAGCGUA
ACCUAUGCGAU
Among the following sets of examples for divergent evolution, select the incorrect option :
Forelimbs of man, bat and cheetah
Heart of bat, man and cheetah
Eye of octopus, bat and man
Brain of bat, man and cheetah
Conversion of milk to curd improves its nutritional value by increasing the amount of
Vitamin D
Vitamin A
Vitamin E
Vitamin B12