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.
Answer:
The correct option is <u><em>A. they evolved from land mammals.</em></u>
Explanation:
The process of evolution explains how closely one organism is to another based on their common ancestors. Scientists believe that those organisms which show many similarities in their structures or functions might have evolved from a common ancestor in the past.
As in the above-mentioned question, scientists have observed that cetaceans lack gills and breath air, this is a property of land mammals. The cetaceans have fin bones which are similar to the limb bones. As limb bones are present in land mammals, hence they cetaceans and land mammals might have common ancestors in the past.
<span>Epigenesis is the term which says that an organism develops from the fertilized egg by a succession of developmental events that leads to an adult. This theory was first published by Aristotle. It became a well established and accepted theory in the late 18th century.</span>
the green light absorbing pigment in the chloroplast traps energy
