Question 71 of 90
Microbes In Human Welfare
Select the correct group of biocontrol agents.
Request an AI explanation using Show explanation.
Year-wise Biology practice
NEET 2019 Biology PYQs
Check your understanding, bookmark questions and revisit your mistakes.
Page score: 0/40
Choose an answer to begin.
Practice scoring: +4 correct, 0 incorrect. Filters apply to this page. Use timed tests for negative marking.
Answers and bookmarks are saved in this browser, across visits. They do not sync to your account.
90 questions in this collection · Page 8 of 9
Question 72 of 90
Biotechnology Principles And Processes
Following statements describe the characteristics of the enzyme Restriction endonuclease. Identify the
incorrect statement.
AI-generated explanation. Check against your textbook.
Explanation:
The incorrect statement is option 1. Restriction endonucleases cut both strands of DNA at specific sites, producing double-stranded breaks (blunt or with sticky ends). They recognize specific palindromic sequences and cut within those sites, breaking the sugar-phosphate backbone on both strands. Options 2, 3, and 4 correctly describe these features as per NCERT biology.
🧠 Did You Know?
Restriction enzymes are essential tools in genetic engineering and cloning, enabling precise cutting and joining of DNA fragments.
💡 NCERT Memory Line:
Restriction endonucleases recognize palindromic DNA sequences and make double-stranded cuts at specific sites.
Question 73 of 90
Organisms And Populations
Pinus seed cannot germinate and establish without
fungal association. This is because:
Request an AI explanation using Show explanation.
Question 74 of 90
Organisms And Populations
Match Column - I with Column - II.
Choose the correct answer from the options given
below:
| Column-I | Column-II |
|---|---|
| (A)Saprophyte | (I)Symbiotic association of fungi with plant roots |
| (B)Parasite | (II)Decomposition of dead organic materials |
| (C)Lichens | (III)Living on living plants or animals |
| (D)Mycorrhiza | (IV)Symbiotic association of algae and fungi |
AI-generated explanation. Check against your textbook.
Explanation:
Correct match: A-Saprophyte ↔ II-Decomposition of dead organic materials; B-Parasite ↔ III-Living on living plants or animals; C-Lichens ↔ IV-Symbiotic association of algae and fungi; D-Mycorrhiza ↔ I-Symbiotic association of fungi with plant roots. So the pairings are (A)-(II), (B)-(III), (C)-(IV), (D)-(I), i.e., option 4. This follows NCERT definitions: saprophytes decompose dead matter; parasites live on hosts; lichens are a fungus-alga mutualism; mycorrhiza is a fungus-plant root symbiosis.
🧠 Did You Know?
Mycorrhiza improves water and nutrient uptake for plants, while lichens can survive in harsh environments due to their composite organism.
💡 NCERT Memory Line:
Saprophytes decompose dead organic materials; Mycorrhiza is a fungus–plant root symbiosis; Parasites live on living hosts; Lichens are a fungus–alga mutualism.
Question 75 of 90
Ecosystem
Which of the following ecological pyramids is
generally inverted?
Request an AI explanation using Show explanation.
Question 76 of 90
Biodiversity And Conservation
Which of the following is the most important causes
for animals and plants being driven to extinction?
Request an AI explanation using Show explanation.
Question 77 of 90
Biodiversity And Conservation
Which one of the following is not a method of in situ conservation of biodiversity?
Request an AI explanation using Show explanation.
Question 78 of 90
Biodiversity And Conservation
The Earth Summit held in Rio de Janeiro in 1992
was called:
Request an AI explanation using Show explanation.
Question 79 of 90
Environmental Issues
Due to increasing air-borne allergens and pollutants, many people in urban areas are suffering from respiratory disorder causing wheezing due to:
Request an AI explanation using Show explanation.
Question 80 of 90
Environmental Issues
Which of the following protocols did aim for reducing emission of chloroflurocarbons into the atmosphere?
Request an AI explanation using Show explanation.
Page score: 0/40