The sphere of living matter together with water, air and soil on the surface of earth is called
atmosphere
hydrosphere
lithosphere
biosphere
D.
biosphere
Biosphere is the biologically inhabited part of earth along with its abiotic or physiochemical components. It consists of three sub- divisions, namely, atmosphere, lithosphere and hydrosphere.
(i) Atmosphere refers to the transparent gaseous mantle surrounding the earth.
(ii) Lithosphere refers to the outer solid crust of earth.
(iii) Hydrosphere is liquid mantle of earth.
In prokaryotes, genetic recombination can occur during
transduction
transformation
conjugation
all of these
During formation of which of the following free nuclear division occurs?
Flower
Endosperm
Gametes
Fruit
Which of the following pesticides is an acetylcholinesterase inhibitor?
Aldrin
BHC
Endosulfan
Malathion
Extranuclear genes occurs in
plastids and are not inherited
plasmid and are not inherited
mitochondria and are inherited by female
mitochondria and are inherited by male
Chloromycetin is obtained from
Streptomyces venezuelae
Streptomyces rimosus
Bacillus subtilis
Clostridium botulinum
Mutualism is found in
hermit crab and sea anemone
ox pecker and rhinoceros
zoochlorellae and Hydra
E.coli and man
Assertion : Watson and Crick provided experimental proof of semiconservative nature of DNA replication.
Reason : DNA polymerase binds nucleotides in replication.
If both Assertion and Reason are true and Reason is the correct explantion of Assertion
If both Assertion and Reason are true and Reason is not the correct explanation of Assertion
If Assertion is true but Reason is false
If Assertion is false but Reason is true.
An oocyte is released from the ovary under the influence of LH
after completing meiosis and before polar bodies are released
after completing meiosis I and before release of polar bodies
after completing meiosis
after completing meiosis I and after release of polar bodies.
