The mean salinity of sea 35 gm per liter. The main cause of this observed salinity is
Evaporation and rainfall
Photosynthesis
Crust erosionand surface run off
Rivers drainage
A.
Evaporation and rainfall
The main cause of salinity is evaporation and rainfall. Salt in the ocean comes from rocks on land. Rain that falls on the land contains dissolved CO2 and in turn, causes the rainwater to be acidic. As rain erodes the rock, acids in the rainwater break down the rock and hence, creates ions or electrically charged particles.
Which statment is not correct for all mammals?
Absence of scales
Absenceof laying egg
Absence of segmentation
Presence of asexual reproduction
Which of the following is the major environmental cue for migration of birds during winter?
Duration of day length
Instinct
Falling temperature
Learning
‘Imperfect fungi’ is a group represented by fungal species which have
Simple mycelia
No known mechanism of sexual reproduction
Unknown phylogenetic relationship
Lost its survival mechanism against harsh environments
Among the following which is typical tree of Indian desert ecosystem?
Prospis cineraria
Avicennia officinalis
Mangifera india
Acer negundo
Which of the following is not an invasive plant species in India?
Parthenium hysterophorus
Salvinia molesta
Lantana camara
Myristica fica
The casual organism for blast of rice is:
Pyricularia grisea
Ustilago tritici
Erwinia chrysanthemi
Cercospora janeseanna
Nilgiri Tahr is restricted only to upper heights (1,200 to 2,600 meters) of Western Ghat. The major reason is
Habitat preferences
Habitat shrinkage
Urbanization in other parts of habitat
Pressure of tiger predation at lower height
On exposure to desiccation which of the following bacteria are least likely to experience rapid water loss?
Isolated rods
Rods in chain
Cocci in chain
Cocci in clusters