7. Chemicals build up in the tissues of organisms over time a. Bioaccumulation b. Biomagnification C . Biological Pests d. Irrigation

## Step 1<br />The question is asking for the term that describes the process where chemicals build up in the tissues of organisms over time. This process is known as bioaccumulation.<br /><br />## Step 2<br />Bioaccumulation refers to the accumulation of substances, such as pesticides or other chemicals, in an organism. These substances can build up in the organism's tissues over time, often due to the organism's inability to break down the substances quickly enough.<br /><br />## Step 3<br />The other options provided, Biomagnification, Biological Pests, and Irrigation, do not accurately describe this process. Biomagnification refers to the increasing concentration of a substance, such as a toxic chemical, in the tissues of organisms at each successive level in a food chain. Biological Pests are organisms that cause damage to crops or livestock, and Irrigation is a method of supplying water to crops.