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

Which one of the following ‘fungi’ is used as a bio-weapon in warfare?

  1. Rhizwus

  2. Pentadiplandra

  3. Aspergillus

  4. Fusarium

  5. Candida
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Harmful chemicals in the form of toxins are called bio-weapons, produced by various species of Fusarium, Myrotecium, Trichoderma, Cephalosporium, etc. The chemicals cause very dangerous diseases to human beings such as bloody diarrhea, weight loss, nervous disorders, cardiovascular alterations, immune-depression, hemostatic derangements, skin toxicity, decreased reproductive capacity and bone marrow damage. Hence, Fusarium is used as a bio-weapon in warfare.

Multiple choice

Directions: For this question, select the best of the answer choices given.

The chanterelle, a type of wild mushroom, grows beneath host trees such as the Douglas fir, which provide it with necessary sugars. The underground filaments of chanterelles, which extract the sugars, in turn provide nutrients and water for their hosts. Because of this mutually beneficial relationship, harvesting the chanterelles growing beneath a Douglas fir seriously endangers the tree. Which of the following, if true, casts the most doubt on the conclusion drawn above?

  1. The number of wild mushrooms harvested has increased in recent years.

  2. Chanterelles grow not only beneath Douglas firs but also beneath other host trees.

  3. Many types of wild mushrooms are found only in forests and cannot easily be grown elsewhere.

  4. The harvesting of wild mushrooms stimulates future growth of those mushrooms.

  5. Young Douglas fir seedlings die without the nutrients and water provided by chanterelle filaments.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The argument assumes that harvesting chanterelles removes them permanently. Option D weakens this by suggesting that harvesting stimulates future growth, meaning the mushrooms could return and continue their beneficial relationship with the trees. This challenges the assumption that harvesting 'seriously endangers' the trees.

Multiple choice

The vegetative plant body of Rhizopus is called:

  1. mycelium

  2. gametangia

  3. sporangiophore

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

Rhizopus is a fungus, and the vegetative body of fungi is called mycelium - a network of thread-like hyphae. Gametangia are reproductive structures, sporangiophore bears spores, and columella is a sterile structure inside the sporangium. Mycelium is the correct answer for the vegetative plant body.