Cell wall is richly impregnated with silica in__________?

A. Rhodophyta
B. Phaeophyta
C. Baciliariophyta
D. Euglenophyta

The cell wall is usually composed of two overlapping halves called epitheca and hypotheca in__________?

A. Diatoms
B. Desmids
C. Pyrrophyta
D. Chlorophyta

Unlike other algae, diatoms do not readily decay due to___________?

A. Nonliving cells
B. Siliceous wall
C. Mucilaginous wall
D. Water proof cell

Centric discoid form of diatoms is__________?

A. Diplaneis
B. Coscinodiscus
C. Camphyloneiscus
D. Stephanodis

Microfossile often present in petroleum producing formationsare those of__________?

A. Diatioms
B. Heliozoans
C. Radiolarians
D. Foraminiferans

Which of the following diseases induce immunity?

A. Smallpox
B. Jaundice
C. Diabetes
D. None of these

Which one of the following organisms can serve as a biofertilizer for rice crop?

A. Blue-green algae
B. Rhizobium sp.
C. Mycorrhizal fungi
D. None of these

“Athlete’s Foot” is a disease caused by_________?

A. Bacteria
B. Fungus
C. Protozoan
D. Nematode

Epiphytes are plants which depend on other plants for________?

A. Food
B. Mechanical support
C. Shade
D. None of these

A line on map connecting places that receives equal solar radiation is called:________?

A. Isobar
B. Isohel
C. Isochore
D. None of these