Answer:
a) calculating the concentration at which 50% of the test organisms of a particular species die
Explanation:
Bioassays -
<u>Bioassays is an analytical method to assess the effect of marine pollutant on the organism by estimating the concentration at which 50% of the test organisms die after exposing the test organisms for a specified time.</u>
It can be done by quantitative or by qualitative experiment , or direct or indirect .
It is used to detect the biological hazards or give the quality assessment of the mixture .
It is also used for the monitoring the quality of water .
Answer:
Explanation:
Native trees have better disease and pest resistance, but how a tree is planted and the site that it is planted in can affect its overall health. Trees that become diseased are often attacked by insects (pests). This is because the disease weakens the tree's defenses, making it vulnerable to infestation by pests.