Consider the following statements about basis of classification.
I. Amphibians are classified on the basis of their habitat.
II. Reptiles are classified on the basis of the nature of their skulls.
III. Birds are classified on the basis of their bones.
IV. Mammals are classified on the basis of their mode of reproduction.
Choose the correct option
Only I
I and II
Only II
II and IV
In biosystematics, the basis of classification is
major morphological characters
cytological characters
evolutionary history considering various parameters from different fields of studies
phenotypic relationships between species
The protein that reproduce within the living cells are termed as
plasmids
phages
prions
prophages
The oldest fossil belongs to which of the following group of plants/ animals?
Asteriodae
Rhodophyceae
Blue- green algae
Phaeophyceae
In Amoeba hyaline cap is formed by
around the food vacuole
around the contractile vacuole
around the nucleus
on pseudopodia
The chief advantage of encystment of an Amoeba is
protection from parasites and predators
the chance to get rid of accumulated waste products
the ability to survive during adverse physical conditions
the ability to live for sometime without ingesting food
Powdery mildew of crops are caused by
bacteria
Ascomycetes
Basidiomycetes
Phycomycetes
B.
Ascomycetes
Mildew diseases are caused by a group of fungal parasites called Ascomycetes. It is of two types powdery mildew and downy mildew.
Powdery mildews are caused by external parasites which grow superficially on the leaves, green stems and fruits and form powdery or dusty patches which are filled with white conidia. Downy mildews are caused by internal obligate parasites which are characterised by downy growth.