Environmental Science

Step 1: Understanding the ANAMMOX process.
ANAMMOX (Anaerobic Ammonium Oxidation) is a biological process in which ammonium is oxidized using nitrite as an electron acceptor under anaerobic conditions.
Step 2: Nature of microorganisms involved.
The microbes responsible for ANAMMOX are chemoautotrophic bacteria that use inorganic carbon (CO ) as their carbon source.
Step 3: Analyzing the options.
(A) Autotrophs: Correct, as ANAMMOX bacteria are autotrophic in nature.
(B) Heterotrophs: Incorrect, they require organic carbon.
(C) Aerobic: Incorrect, ANAMMOX occurs under anaerobic conditions.
(D) Phototrophs: Incorrect, light is not involved.
Step 4: Conclusion.
The ANAMMOX process is dominated by autotrophic microorganisms.

Step 1: Understanding membrane filtration.
Membrane processes are classified based on pore size, which determines the size of particles or solutes removed from water.
Step 2: Relative pore sizes.
Microfiltration (MF) has the largest pore size, followed by Ultrafiltration (UF), then Nanofiltration (NF), while Reverse Osmosis (RO) has the smallest effective pore size.
Step 3: Evaluating the options.
(A) Incorrect, NF does not have larger pores than MF.
(B) Correct, this follows decreasing pore size from MF to RO.
(C) Incorrect, UF pores are smaller than MF.
(D) Incorrect, RO has the smallest pores, not the largest.
Step 4: Conclusion.
The correct sequence according to decreasing pore size is MF > UF > NF > RO.

Step 1: Understanding autotrophs.
Autotrophs are organisms that can synthesize their own organic food from inorganic substances. They use inorganic carbon, mainly in the form of carbon dioxide, as the carbon source.
Step 2: Source of energy and carbon.
Autotrophs obtain energy either from sunlight (photoautotrophs) or from chemical reactions (chemoautotrophs), but their carbon source always remains inorganic.
Step 3: Analyzing the options.
(A) Incorrect, utilization of organic carbon is a characteristic of heterotrophs.
(B) Correct, as autotrophs utilize inorganic carbon such as CO .
(C) Incorrect, nitrogen source does not define autotrophic nature.
(D) Incorrect, since option A itself is incorrect.
Step 4: Conclusion.
Autotrophs are correctly defined as organisms that utilize inorganic carbon.

Step 1: Understanding biological magnification.
Biological magnification refers to the increase in concentration of toxic substances, such as pesticides, at successive trophic levels of an ecosystem.
Step 2: Movement of pesticides in ecosystems.
Pesticides enter producers first and then pass to herbivores and carnivores through feeding relationships, increasing in concentration at each level.
Step 3: Analyzing the options.
(A) Incorrect, population pyramids show population structure, not toxin transfer.
(B) Incorrect, hydrological cycle involves water movement only.
(C) Correct, food chains transfer pesticides across trophic levels.
(D) Incorrect, air cycle does not cause magnification in organisms.
Step 4: Conclusion.
Biological magnification of pesticides occurs through food chains.