Biological Classification — Page 6 | NEET Biology

Q51

Ustilago causes plant diseases called smut because

A they parasitise cereals

B mycelium is black

C they develop sooty masses of spores

D affected parts become completely black

Correct Answer

Option D

Solution

(d) Smut disease is caused by Ustilago species and the affected part becomes black.

Q52

Claviceps purpurea is causal organism of

A Smut of Barley

B Rust of Wheat

C Ergot of Rye

D Powdery Mildew of Pea

Correct Answer

Option C

Solution

(c) The fungus that causes Ergot of Rye is Claviceps purpurea.

Q53

Which fungal disease spreads by seed and flowers?

A Loose smut of wheat

B Corn stunt

C Covered smut of barley

D Soft rot of potato

Correct Answer

Option A

Solution

(a) Ustilago causes loose smut of wheat, converting grain and flower into powdered mass.

Q54

The imperfect fungi which are decomposers of litter and help in mineral cycling belong to:

A Basidiomycetes

B Phycomycetes

C Ascomycetes

D Deuteromycetes

Correct Answer

Option D

Solution

(d) Class Deuteromycetes comprises imperfect fungi which play a role in decomposition of organic wastes.

Q55

The chemical compounds produced by the host plants to protect themselves against fungal infection are

A phytotoxin

B pathogen

C phytoalexins

D hormone

Correct Answer

Option C

Solution

(c) Phytoalexins are non-specific antibiotic substances produced by plants in response to infection by a fungus.

Q56

Black rust of wheat is caused by

A Puccinia

B Mucor

C Aspergillus

D Rhizopus

Correct Answer

Option A

Solution

(a) Black rust of wheat is caused by Puccinia graminis.

Q57

Mycorrhiza is

A a symbiotic association of plant roots and certain fungi

B an association of algae with fungi

C a fungus parasitising root system of higher plants

D an association of Rhizobium with the roots of leguminous plants

Correct Answer

Option A

Solution

(a) Mycorrhiza is a symbiotic association between fungi and roots of higher plants.

Q58

A good green manure in rice fields is

A Aspergillus

B Azolla

C Salvinia

D Mucor

Correct Answer

Option B

Solution

(b) Azolla harbors blue-green algae Anabaena which fixes N2, increasing fertility.

Q59

In the five-kingdom system of classification, which single kingdom out of the following can include blue green algae, nitrogen-fixing bacteria and methanogenic archaebacteria?

A Fungi

B Plantae

C Protista

D Monera

Correct Answer

Option D

Solution

(d) Monera is the prokaryotic kingdom that includes bacteria, blue green algae and archaebacteria.

Q60

Pick up the wrong statement

A Protista have photosynthetic and heterotrophic modes of nutrition

B Some fungi are edible

C Nuclear membrane is present in Monera

D Cell wall is absent in Animalia

Correct Answer

Option C

Solution

(c) The kingdom Monera possesses prokaryotic organisms having no nuclear membrane.