R4RIN – MCQs, Mock Tests | Biology MCQs Question and Answer -Biology Set 4

 The ‘lock and key hypothesis’ mechanism is related with:

1. Digestion of fat in the body
2. For enzyme specificity
3. For the formation of vacuole
4. Explosives

✅ Correct Answer: 2

Which disease of plant is known as ring disease?

1. Citrus Canker
2. Black arm of cotton
3. Wilt of Potato
4. None of the above

✅ Correct Answer: 3

Name the disease of plant in which large yellow spot appears on the leaves?

1. Bacterial Blight
2. Bacterial Spot
3. Aphids
4. Botrytis

✅ Correct Answer: 1

Bunchy top of banana plant disease is caused due to:

1. Bacteria
2. Fungus
3. Virus
4. None of the above

✅ Correct Answer: 3

Name a disease of plant in which dark to light brown rot forms around wounded plant tissue?

1. Gray Mold
2. Citrus Canker
3. Spider Mites
4. None of the above

✅ Correct Answer: 1

In which disease of plant white mildew appears typically on underside of leaves?

1. Cylindrocladium
2. Angular leaf Spot
3. Downy Mildew
4. Black arm of Cotton

✅ Correct Answer: 3

Bacterial blight of Rice disease of plant is caused due to which bacteria?

1. Pseudomonas bacteria
2. Xanthomonas citri bacteria
3. Xanthomonas oryzae bacteria
4. None of the above

✅ Correct Answer: 3

In which of the following diseases of plant chlorophyll of the leaves get destroyed and leaves get shrinked?

1. Mosaic disease of tobacco
2. Citrus Canker
3. Tundu disease of wheat
4. Rhizoctonia

✅ Correct Answer: 1

Name the disease of plant in which leaves, branches, fruits all are affected?

1. Spider Mites
2. Mealybugs
3. Aphids
4. Citrus Canker

✅ Correct Answer: 4

Name a disease of plant in which fine webbing occurs on undersides of the leaves?

1. Spider Mites
2. Anthracnose
3. Mealybugs
4. Rhizoctonia

✅ Correct Answer: 1

In which disease of plant stem rot at soil line with brown to red lesions?

1. Rhizoctonia
2. Angular leaf Spot
3. Bacterial Blight
4. Bacterial Spot

✅ Correct Answer: 1