Biology

Microbes and Plant Diseases

1,145 Questions

Microbes and plant diseases examine the role of fungi, bacteria, and viruses in causing infections in plants and humans. Topics cover symbiotic associations like mycorrhiza, fungal structures, and specific agricultural pathogens. Practice these biology questions to master microbiology concepts for upcoming competitive examinations.

Fungal associationsPlant pathogensMicrobial structuresBacterial infections

Microbes and Plant Diseases Questions

Multiple choice evs whose forests? improved methods of agriculture cropping patterns food for all conservation of forest and wildlife wildlife deforestation and conservation

Xanthium, Parthenium, Cyperus rotundus are the examples of 

  1. Diseases

  2. Pesticides

  3. Weeds

  4. Pathogens
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Weeds are unwanted plants which grow along with the crop plants in the cultivated field. Some common weeds in India are Amaranthus (Chaulai), Parthenium (Gajar ghas), Cyperus rotundus (Motha), Chenopodium (Bathua), Xanthium (Gokhroo). Weeds compete with the crop plants for nutrients, space, light and water. This results in lowering the food grain quality and reduction in crop yield. Weeds may produce toxic substances which may interfere with crop growth. During harvesting, weeds get mixed up with crops to lower down its quality.

So, the correct answer is 'Weeds'.

Multiple choice botany know the plant world closely nutrition and its types types of nutrition in plants different modes of nutrition in plants

A fungus which grows on a host but can also subsist on organic matter is

  1. Obligate parasite

  2. Obligate saprophyte

  3. Facultative saprophyte

  4. Facultative parasite
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A facultative saprophyte is an organism that is primarily a parasite but can survive as a saprophyte if a living host is unavailable.

Multiple choice botany know the plant world closely nutrition and its types types of nutrition in plants different modes of nutrition in plants

A partial parasite is?

  1. Cuscuta

  2. Cassytha

  3. Arceuthobium

  4. Viscum
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Viscum is a partial stem parasite among the following because it depends on its host for only water and minerals. It can prepare its own food through photosynthesis as it is chlorophyllous.

So the correct option is 'Viscum'.

Multiple choice botany know the plant world closely nutrition and its types types of nutrition in plants different modes of nutrition in plants

Which one of the following is a total root parasite?

  1. Balanophora$/$ Orobanche

  2. Viscum

  3. Cassytha

  4. Drosera
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Balanophora is a total root parasite because it sucks sugars, minerals and also water from the roots of host plants like cabbage etc for its survival, in turn, harming the host.

So, the correct option is 'Balanophora/ Orobanche'.

Multiple choice botany know the plant world closely nutrition and its types types of nutrition in plants different modes of nutrition in plants

Which one of the following is a total parasite ?

  1. Nepenthes

  2. Rhozobium

  3. Cuscuta

  4. Lichens
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A.Nepenthes - It is an insectivorous plant.

B.Rhizobium - Rod shaped, aerobic, Nitrogen fixing bacterium.
C.Cuscuta - complete stem parasite.
D.Lichens - Special type of plants formed by the association of algae and fungi.
So, the correct option is 'Cuscuta'

Multiple choice zoology ecosystems decomposition in ecosystem ecosystem productivity and decomposition producers, consumers and decomposers

Microorganism act upon a dead plant to produce

  1. Humus

  2. Mushroom

  3. Wood

  4. Sand
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Dead plants and animals are degraded in soil by decomposing bacteria and fungi. The material formed after the decomposition process is called humus. Humus is very rich in nutrients and black in colour. Greater the amount of humus more is the soil productivity. Thus, the correct answer is option A.

Multiple choice biology biodiversity and classification monera five kingdoms of living organisms biodiversity and need of classification

Death factor is secreted by 

  1. BGA

  2. Archaebacteria

  3. Fungi

  4. Mycoplasm
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cyanobacteria (Blue-green algae or BGA) sometimes reproduce exponentially to form blooms. Blooming cyanobacteria can secrete death factors in such concentrations that they poison and even kill animals and humans. It can also accumulate in other animals such as fish and shellfish and cause poisonings such as shellfish poisoning.

So, the correct answer is 'BGA'.

Multiple choice biology biodiversity and classification monera five kingdoms of living organisms biodiversity and need of classification

Plant decomposers are _______________.

  1. Monera and Fungi

  2. Fungi and Plantae

  3. Protista and Animalia

  4. Animalia and Monera
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Decomposers are living components mainly the bacteria and fungi that break down the complex compounds of the dead protoplasm of producers and consumers absorb some products and release others.
So, the correct answer is 'Monera and Fungi'
Multiple choice biology biodiversity and classification monera five kingdoms of living organisms biodiversity and need of classification

Ray fungi are

  1. Phycomycetes

  2. Ascomycetes

  3. Actinomycetes

  4. Basidiomycetes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ray fungi are also called as Actinomycetes. They form a mycelium consisting of narrow hyphae. They show characteristics of both fungi and bacteria. They form the normal part of the mouth flora in the human. They produce many antibiotics like streptomycin, actinomycin and chloromycin. 

Thus, the correct answer is 'Actinomycetes.'

Multiple choice botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

Torula condition' occurs in ________.

  1. Rhizopus

  2. Ulothrix

  3. Spirogyra

  4. Riccia
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
When some species of like mucor they grow in high concentrated liquid medium of sugar and they brown up into small pieces called odia and further they grow like yeast by budding and this condition called Torula condition.
Hence the correct answer is A. 
Multiple choice evs - i community health and hygiene drug, tobacco and alcohol consumption addiction and dependence important stages in agricultural development disorders of nervous system

Cyclosporin A, an immunosuppressive drug is produced by

  1. Aspergillus niger

  2. Monascus purpureus

  3. Penicillium notatum

  4. Trichoderma polysporum
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cyclosporin is used as immuno depressant, this drug is derived from a fungus Trichoderma polysporum and inhibit the activity of helper - T cells, thus help to prevent rejection of organ transplant.

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Name one frequently used fungicide from the following.

  1. Griseofulvin

  2. Chloramphenicol

  3. Cycocel

  4. Ethylene
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Griseofulvin is an orally administered antifungal drug. It is used both in animals and humans, to treat fungal infections of the skin (commonly known as ringworm) and nails. It is produced by culture of some strains of the mold Penicillium griseofulvum, from which it was isolated in 1939.