Ecology Basics — Set 5
Geography · पारिस्थितिकी की मूल बातें · Questions 41–50 of 50
Which of the following is a major 'Gaseous' biogeochemical cycle?
Correct Answer: A. Carbon Cycle
The carbon cycle is a gaseous cycle because its main reservoir is the atmosphere in the form of $CO_2$. Photosynthesis and respiration are the key biological processes in this cycle. Nitrogen and Oxygen are other examples of gaseous cycles.
What is the maximum number of individuals of a species that a habitat can support indefinitely?
Correct Answer: D. Carrying Capacity
Carrying capacity refers to the population size that an environment can sustain given available resources. Once a population exceeds this limit, resource depletion and deaths usually follow. It is represented by the symbol 'K' in population models.
Animals that depend on other animals for food are collectively called?
Correct Answer: D. Consumers
Consumers are heterotrophs that cannot make their own food and must ingest other organisms. They are classified into primary (herbivores), secondary, and tertiary consumers. All animals and some parasitic plants are consumers.
The study of the relationship between entire communities of organisms and their environment is?
Correct Answer: A. Synecology
Synecology is the study of community ecology, dealing with interactions within and between species groups. It examines how different populations coexist and interact in a single ecosystem. This is distinct from autecology, which focuses on a single species.
Which ecosystem has the highest primary productivity in the world?
Correct Answer: D. Tropical Rainforests
Tropical rainforests have very high primary productivity due to abundant sunlight and year-round warm temperatures. This massive energy production supports the highest levels of biodiversity on Earth. Coral reefs are another ecosystem with similarly high productivity.
In a grazing food chain, the first link is always a?
Correct Answer: D. Green plant
A grazing food chain begins with green plants, also known as producers, which perform photosynthesis. The second link is always a herbivore that eats the plant. This is the most common type of food chain in terrestrial ecosystems.
The 'Pyramid of Numbers' can be inverted in which specific case?
Correct Answer: A. Forest (Single tree ecosystem)
In a single tree ecosystem, the pyramid of numbers is inverted as one large tree supports many herbivorous birds and even more parasites. Here, the number of individuals increases at each successive trophic level. This is a rare exception to the typically upright number pyramid.
What is the group of all the ecosystems on Earth called?
Correct Answer: A. Biosphere
The biosphere is the worldwide sum of all ecosystems, representing the zone of life on Earth. it integrates all living beings and their relationships, including their interaction with the elements of the lithosphere and atmosphere. It is the largest ecological level of organization.
Which of the following describes the relationship in 'Mutualism'?
Correct Answer: D. (+, +)
Mutualism is indicated by (+, +) because both interacting species derive benefits from each other. An interaction like parasitism is marked as (+, -) because one benefits and the other is harmed. Commensalism is (+, 0) because one benefits and the other remains unaffected.
What percentage of Earth's water is freshwater?
Correct Answer: C. 2.5%
Only about 2.5% of Earth's total water is freshwater. Of this, about 68.7% is locked in ice caps and glaciers, and only about 0.3% is in accessible surface freshwater like rivers and lakes.