1.
What is the full form of BOD?
Correct Answer
B. Biochemical Oxygen Demand
Explanation
Biochemical Oxygen Demand (BOD) is the correct full form for BOD. BOD is a measure of the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample. It is a crucial parameter used to assess the level of organic pollution in water bodies and determine their overall health. The other options, such as Biological Oxygen Deduction, Biology Oxygen Deman, and Biome Oxygen Demand, do not accurately represent the correct full form of BOD.
2.
The biochemical oxygen demand (BOD) of the water tends to _____ where algal blooms are present.
Correct Answer
B. Increase
Explanation
The presence of algal blooms in water leads to an increase in the biochemical oxygen demand (BOD). Algal blooms are caused by an excessive growth of algae, which consume large amounts of oxygen during their decomposition process. As a result, the BOD of the water increases, indicating a higher demand for oxygen to break down the organic matter. This can lead to a decrease in dissolved oxygen levels, negatively affecting aquatic life and water quality.
3.
The biological oxygen demand is a commonly used for
Correct Answer
D. Pollution assay in aquatic ecosystems
Explanation
Biological oxygen demand (BOD) is a commonly used method to assess the pollution levels in aquatic ecosystems. BOD measures the amount of oxygen consumed by microorganisms in water while decomposing organic matter. Higher BOD levels indicate higher pollution, as more organic matter is present in the water, leading to increased microbial activity and oxygen consumption. Therefore, BOD is an effective tool to determine the extent of pollution in aquatic environments.
4.
Algal blooms usually occur
Correct Answer
B. Where water is slow-flowing or stagnant,
Explanation
Algal blooms usually occur where water is slow-flowing or stagnant. This is because slow-moving or stagnant water provides the ideal conditions for the growth and proliferation of algae. These conditions allow for the accumulation of nutrients, such as nitrogen and phosphorus, which are essential for algal growth. Additionally, the lack of water movement inhibits the dispersal of algae, leading to their concentration in one area and the formation of algal blooms.
5.
For biomagnification to occur, pollutants must be
Correct Answer
D. All of the above
Explanation
Biomagnification is the process in which pollutants, such as heavy metals or pesticides, become increasingly concentrated as they move up the food chain. For this process to occur, the pollutants must possess certain characteristics. They need to be long-lived, meaning that they persist in the environment for a significant amount of time. They also need to be mobile, so they can be transported through air, water, or soil. Additionally, the pollutants must be biologically active, meaning that they can interact with living organisms and cause harmful effects. Therefore, all of the given options - long-lived, mobile, and biologically active - are necessary for biomagnification to occur.
6.
Ocean Acidification lowers the pH of water.
Correct Answer
A. True
Explanation
Ocean acidification is a process that occurs when carbon dioxide from the atmosphere is absorbed by seawater, resulting in a decrease in pH. This decrease in pH makes the water more acidic, hence lowering the pH of the water. Therefore, the statement "Ocean Acidification lowers the pH of water" is true.
7.
The process that occurs at all trophic levels in an aquatic environment is called
Correct Answer
C. Biodilution
Explanation
Biodilution is the correct answer because it refers to the process that occurs at all trophic levels in an aquatic environment. Biodilution happens when the concentration of a substance decreases as it moves up the food chain. This occurs because the substance is diluted in the bodies of organisms at each trophic level, resulting in lower concentrations at higher levels. Bioremediation refers to the use of living organisms to clean up pollutants, while biomagnification refers to the increase in concentration of a substance as it moves up the food chain.
8.
No two species in a habitat can have the same niche.
Correct Answer
A. True
Explanation
This statement is true because a niche refers to the specific role or position that a species occupies within its habitat. It includes factors such as the resources it uses, the way it interacts with other species, and its specific adaptations. If two species were to have exactly the same niche, they would be competing for the same resources and occupying the same ecological space, which would lead to intense competition and one species eventually outcompeting the other. Therefore, in order to avoid direct competition, species in a habitat tend to have different niches.
9.
Which of the following is not an example of toxins?
Correct Answer
D. Water
Explanation
Water is not an example of toxins because it is a natural substance that is essential for life. While certain pollutants or contaminants can be present in water and may be harmful, water itself is not inherently toxic. Pesticides, mercury, and insecticides, on the other hand, are all examples of toxins as they can have harmful effects on living organisms.
10.
Branch of ecology that deals with the ecological interrelationships among communities of organisms is called
Correct Answer
B. Synecology
Explanation
Synecology is the branch of ecology that focuses on studying the ecological interrelationships among communities of organisms. It examines how different species within a community interact with each other and their environment. This includes studying the dynamics of populations, species interactions such as competition and predation, and the flow of energy and nutrients within the community. Organismal ecology, on the other hand, focuses on the individual organisms and their adaptations to their environment, while ecosystem ecology studies the interactions between organisms and their physical environment. Therefore, the correct answer is Synecology.