Nitrogen fixation takes place by……in soil.
a) Rhizobium
b) cyanobacteria
c) both a and b
d) none of them
Clostridium species live as normal flora in human in…….
a) colon
b) mouth
c) vagina
d) nose
Cyanobacteria……..
a) are poisoned by oxygen
b) have chlorophyll
c) have chloroplast
d) are not widely distributed
Pili are made up of pilin which is……
a) triglyceride
b) protein
c) lipid
d) glycoprotein
Most pathogenic bacteria cause diseases by…….
a) depriving the host by oxygen
b) producing toxins
c) depriving the host by nutrients
d) directly destroying host cells
Chemosynthetic bacteria…….
a) are autotrophic
b) oxidize inorganic compounds to acquire energy
c) use the sun rays
d) both a and b
