If decomposers are removed what will happen to the ecosystem?
Energy cycle is stopped
Mineral cycle is stopped
Consumers cannot absorb solar energy
Rate of decompostion of mineral increases
Which of the following is used as green manure?
Azolla
Azadirachta
Crotolaria juncea
Hevea brassiliansis
Among plants "pheromones" are secreted by the cells of the following plants for given function
all plants for growth and development
Yeast for facilitating mating
all fungi for sexual reproduction
Rhizopus for formation of zygospore
The gases that produce green house gases are
CH4, CFCs, CO2
CO2, N2O, H2
CFCs, NO2, O2
CO2, N2, water vapour
Increase in toxic concentration from one trophic level to another trophic level is called
ecological toxification
bio- magnification
bioconcentration
cytological effect
Which of the following workers are related as ecologist, palaeobotanist and embryologist respectively?
B. Salmi, R. Mishra, P. Maheshwari
R Mishra, B. Sahni, P. Maheshwari
B. Sahni, P. Maheshwari, R Mishra
P. Maheshwari, R Mishra, B. Sahni
The Triticale is an intergeneric hybrid between
wheat and maize
maize and rye
wheat and rye
bajra and wheat
For the formation of tetrasporic embryosac, how many megaspore mother cells are required?
1
2
3
4
DNA replication generally proceeds in a
5 3 direction
3 5 direction
3 3 direction
5 5 direction
A.
5 3 direction
DNA is made up of double helix of two complementary strands. Both the strands get seperated during replication. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, hence, a process is known as semi- conservative replication.
DNA synthesis or replication always proceeds in 5' 3' direction because DNA polymerase acts on the 3'- OH of the existing strand for adding the free nucleotides.