Read the following statements regarding archaebacteria.

I. Their cell wall lacks peptidoglycan.

II. They contain membrane bound organelles.

III. These have distinct ribosomal RNA sequence.

IV. Lipid in cell membrane of archaebacteria have different structure than those in all other organisms.

Choose the incorrecct option.

(1) I and II

(2) Only II

(3) Only IV

(4) III and IV

A bacterium divides every 35 minutes. If a culture containing 10⁵ cells/mL is grown for 175 minutes, what will be the cell concentration/mL after 175 minutes?

(1) 5 × 10⁵ cells

(2) 35 × 10⁵ cells

(3) 32 × 10⁵ cells

(4) 4.175 × 10⁵ cells

Dikaryotisation (n + n) in Agaricus is brought about by

(1) clamp connections

(2) somatogamay between two hyphae of different strains

(3) Both (1) and (2) are correct

(4) basidiospores

'Red tide' is caused by

(1) Gonyaulax

(2) Ceratium

(3) Triceratium

(4) All of these

Which one of the following shows heterothallism?

(1) Rhizopus

(2) Bacterium

(3) Cycas

(4) Ricinus

The common characteristic showning by mushroom, smut and rust

(1) is characterised by presence of basidiocarps

(2) is characterised by presence of ascocarps

(3) all are pathogen

(4) all are saprophytic in nature

Which one exhibits the character of a protozoan during one phase of its life cycle and character of fungi in another phase of its life cycle?

(1) Water moulds

(2) Psilophytes

(3) Slime moulds

(4) Diatoms

Spirochaetes is/are

(1) a class of viruses

(2) myxobacteria

(3) spiral-shaped bacteria

(4) richittsias

Spirochaetes is are

(1) a class of insects

(2) a class of viruses

(3) bacteria

(4) fungi

The metachromatic granules are

(1) present in plants cell at metaphase stage

(2) inclusion bodies in bacteria

(3) produced in insects during metamorphosis

(4) chromatophores in animals skin