D. A variable or alteration to one part that affects an entire system
Explanation:
When talking about natural and physical systems, change is a variable or alteration to one part that affects an entire system.
Systems are groups of processes that have the same overall function. There are several types of interacting components that makes up both physical and natural systems in our world.
- The part of system is related and interconnected via the changes they undergo.
- Changes typically causes variation or alteration of parts of a system.
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Biogeochemical cycle brainly.com/question/3509510
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Answer:
They are used as an indicator organism for pathogenic bacteria.
Explanation:
Coliforms are bacteria found in digestive tract of animals and humans. They are non-pathogenic, easy to culture and are used as an alternative indirect testing for presence of other microorganisms. Coliforms thrive in exact environmental conditions like other pathogenic bacteria, thus often used to indicate whether they are bacteria found in drinking water and swimming pools that might end up causing infections.
Therefore the existence of coliforms in water easily indicates feacal contamination.
