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

Phylogenetic system of classification includes

(1) evolutionary trends only

(2) genetic trends only

(3) evolutionary trend as well as morphology

(4) behavioural trends in environment

'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

Which of the following is a 'cyanophage'?

(1) S-13

(2) $\varphi \times 174$

(3) SV-40

(4) LPP-1

Match items in Column I with those in Column II.

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