Biological Classification

Lichens are well known combination of an alga and a fungus where fungus has

1. a saprophytic relationship with the alga
2. an epiphytic relationship with the alga
3. a parasitic relationship with alga
4. a symbiotic relationship with alga

When a fresh-water protozoan possessing a contractile vacuole, is placed in a glass containing marine water, the vacuole will

1. increase in number
2. disappear
3. increase in size
4. decrease in size

Which one of the following statements about viruses is correct?

1. Viruses possess their own metabolic system.
2. All viruses contain both RNA and DNA.
3. Viruses are obligate parasites.
4. Nucleic acid of viruses is known as capsid.

Tobacco mosaic virus is a tubular filament of size

1. 300 10 nm
2. 300 5 nm
3. 300 20 nm
4. 700 30 nm

Viruses are no more "alive" than isolated chromosomes because

1. they require both RNA and DNA
2. they both need food molecules
3. they both require oxygen for respiration
4. both require the environment of a cell to replicate.

In which kingdom would you classify the archaea and nitrogen-fixing organisms, if the five-kingdom system of classification is used?

1. Plantae
2. Fungi
3. Protista
4. Monera

The chief advantage of encystment of an Amoeba is

1. the ability to survive during adverse physical conditions
2. the ability to live for some time without ingesting food
3. protection from parasites and predators
4. the chance to get rid of accumulated waste products.

In five kingdom system, the main basis of classification is

1. structure of nucleus
2. mode of nutrition
3. structure of cell wall
4. asexual reproduction.

Which statement is correct for bacterial transduction?

1. Transfer of some genes from one bacterium to another bacterium through virus.
2. Transfer of genes from one bacterium to another bacterium by conjugation.
3. Bacterium obtained its DNA directly from mother cell.
4. Bacterium obtained DNA from other external source.

Which fungal disease spreads by seed and flowers?

1. Loose smut of wheat
2. Corn smut
3. Covered smut of barley
4. Soft rot of potato