The IUCN Red List is based on a set of criteria to evaluate species vulnerability to extinction. Which one or more of the options is/are used as criteria?
Show Hint
- Absolute population size
- Geographic range
- Economic value
- Change in population size over time
The Correct Option is A, B, D
Solution and Explanation
Plant–Mycorrhizal Fungi Interactions
Step 1: Recall what mycorrhizae do.
Mycorrhizal fungi exchange soil nutrients (P, N, water) for photosynthate (carbon) from plant roots. The net effect depends on soil nutrient availability.
Step 2: Classify interactions by cost–benefit to the plant.
- Nutrient-poor soils: Fungal hyphae enhance nutrient uptake. Plant gains more than it pays in carbon. \(\Rightarrow\) Mutualism → (C) true.
- Nutrient-rich soils: Plant can acquire nutrients without fungus; fungus still takes carbon. Plant pays cost with little or no return. \(\Rightarrow\) Parasitism → (A) true.
- Intermediate/neutral cases: Net plant effect ≈ 0 while fungus still gains carbon. \(\Rightarrow\) Commensalism → (D) can occur.
Step 3: Eliminate the incorrect option.
(B) Predation involves killing or consuming another organism; mycorrhizal colonization does not fit this definition.
Final Answer: \[ \boxed{\text{(A) Parasitism, \quad (C) Mutualism, \quad (D) Commensalism}} \]
Top Questions on Ecology
- (a) Indiscriminate human activities such as alien species invasion, fragmentation and habitat loss have accelerated the loss of biodiversity. Justify by taking one example for each.
(b) State the importance of the following:
(i) IUCN Red data list
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Questions Asked in GATE EY exam
Here are two analogous groups, Group-I and Group-II, that list words in their decreasing order of intensity. Identify the missing word in Group-II.
Abuse \( \rightarrow \) Insult \( \rightarrow \) Ridicule
__________ \( \rightarrow \) Praise \( \rightarrow \) Appreciate
- Which one of the following mechanisms is expected to generate tightly linked genes?
- GATE EY - 2025
- Genetics
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The overhead is 20% of the consulting fee if the fee is up to ₹5,00,000.
For higher fees, the overhead is ₹1,00,000 plus 10% of the amount by which the fee exceeds ₹5,00,000.
The government charges a Goods and Services Tax (GST) of 18% on the total amount (i.e., the consulting fee plus the overhead).
An employee of the organization charges this entire amount — that is, the consulting fee, overhead, and tax — to the client.
If the client cannot pay more than ₹10,00,000, what is the maximum consulting fee that the employee can charge? The table lists the top 5 nations according to the number of gold medals won in a tournament; also included are the number of silver and the bronze medals won by them. Based only on the data provided in the table, which one of the following statements is INCORRECT?
Eight students (P, Q, R, S, T, U, V, and W) are playing musical chairs. The figure indicates their order of position at the start of the game. They play the game by moving forward in a circle in the clockwise direction.
After the 1st round, the 4th student behind P leaves the game.
After the 2nd round, the 5th student behind Q leaves the game.
After the 3rd round, the 3rd student behind V leaves the game.
After the 4th round, the 4th student behind U leaves the game.
Who all are left in the game after the 4th round?