Answer:
The correct answer is - warning system.
Explanation:
Warning systems are a type of system that could be technical or biological in nature that can help in assessing or inform about the possible danger or change in a particular setting such as ecosystem, weather, water quality, and many others. It helps in avoiding such threats before occurring or become serious threats.
Certain biological species that live or require a particular set of conditions for their survival and reproduction can act as a biological warning system for water pollution, air pollution.
Answer:
c - having controlled experiments within ethical limits.
Explanation:
False
Not always, some proteins are used in a variety. <span>Protein channels are needed to transport substances because it accelerates the transport process. Very few substances enter or leave cells without being attached to a transport protein. Different types of substances require different types of proteins to transport them. Protein channels transport water or ions downwards and ATP-powered pumps transport molecules or ions upwards. ATP generates energy to transport the molecules upwards. </span>