Some hyperthermophilic organisms that grow in highly acidic (pH2) habitats belongs to the two groups called
eubacteria and archaea
cyanobacteria and diatoms
protists and mosses
protists and mosses
Genetic engineering has been successfully used for producing
transgenic mice for testing safety to polio vaccine before use in humans
transgenic models for studying new treatments for certain cardiac diseases
transgenic cow -Rosie which produces high-fat milk for making ghee
transgenic cow -Rosie which produces high-fat milk for making ghee
Some of the characteristics of Bt cotton are
long fibre and resistance of aphids
medium yield, long fibre and resistance to beetle pests
high yield and production of toxic protein crystals which kill dipteran pests
high yield and production of toxic protein crystals which kill dipteran pests
Satellite DNA is useful tool in
Organ transplantation
sex determination
forensic science
forensic science
The second maturation division of the mammalian ovum occurs
shortly after ovulation before the ovum makes entry into the fallopian tube
until after the ovum has penetrated by a sperm
until the nucleus of the sperm has fused with that of the ovum
until the nucleus of the sperm has fused with that of the ovum
Which one of the following does not follow the central dogma of molecular biology?
Pea
Mucor
Chlamydomonas
Chlamydomonas
Which one of the following statements about human sperm is correct?
Acrosome has a conical pointed structure used for piercing and penetrating the egg, resulting in fertilisation
The sperm lysis in the acrosome dissolve the egg envelope facilitating fertilization
Acrosome serves as a sensory structure leading the sperm towards the ovum
Acrosome serves as a sensory structure leading the sperm towards the ovum
B.
The sperm lysis in the acrosome dissolve the egg envelope facilitating fertilization
Penetration of human sperm is a chemical mechanism. In this, acrosome of sperm udergoes acrosomal reaction and release certain sperm lysins, which dissolves the egg envelope locally and makes the path for the penetration of sperm. Sperm lysins are acidic proteins. These sperm lysins contain a lytic enzyme hyaluronidase that dissolves the hyaluronic acid polymers in the intercellular spaces, which holds the granulosa cells of corona radiate together corona penetrating enzyme and acrosin.
Wind pollinated flowers are
small, brightly coloured, producing large number of pollen grains
small, producing large number of dry pollen grains
large, producing abundant nectar and pollen
large, producing abundant nectar and pollen
dB is a standard abbreviation used for the quantitative expression of
the density of bacteria in a medium
a particular pollutant
the dominant Bacillus in a culture
the dominant Bacillus in a culture