Ecology And Environment

Step 1: Understanding the Question.
The question asks about the contributions of Alexander von Humboldt to ecological science, focusing on the relationship between species and their environment.

Step 2: Analyzing the Options.
(A) The relationship of species distribution: Correct — Humboldt was one of the first to describe how species are distributed across different geographic regions and the environmental factors influencing this distribution.
(B) Population growth equation: This was not a primary focus of Humboldt's work. This concept is more associated with figures like Malthus.
(C) The principle of limiting factors: Humboldt did discuss environmental limits, but his primary focus was on species distribution.
(D) Ecological biodiversity: While Humboldt contributed to understanding ecosystems, this term is more associated with later ecological studies.

Step 3: Conclusion.
The correct answer is (A) The relationship of species distribution, as Humboldt is known for his work on species distribution and the factors affecting it.

Step 1: Understanding the Question.
This question focuses on the type of food that supports the largest population, taking into consideration the energy and nutrition provided by each food type.

Step 2: Analyzing the Options.
(A) Fruits: While fruits are nutritious, they do not support as large a population as other food sources.
(B) Vegetables: Vegetables are important but still do not support the same population as seeds.
(C) Seeds: Correct — Seeds, such as grains, provide a high-calorie food source that supports large populations.
(D) Dairy products: Dairy products are nutritious but are less common globally compared to seeds.

Step 3: Conclusion.
The correct answer is (C) Seeds, as seeds are a major food source for many people around the world.

Step 1: Understanding the Question.
The question describes a relationship where one organism benefits while the other remains unaffected, which is characteristic of commensalism.

Step 2: Analyzing the Options.
(A) Parasitism: In parasitism, one organism benefits at the expense of the other, so this is not correct.
(B) Commensalism: Correct — Commensalism is a symbiotic relationship where one organism benefits, and the other is neither helped nor harmed.
(C) Mutualism: This involves both organisms benefiting, which is not the case here.
(D) Predation: In predation, one organism benefits by killing the other, so this is not correct.

Step 3: Conclusion.
The correct answer is (B) Commensalism, as it perfectly fits the description of one organism benefiting while the other remains unaffected.