Suppose that a certain enzyme is synthesized whenever the solution in which the cells aregrowing contains substance Y. When substance Y is not present, the enzyme is produced onlyunder certain environmental conditions. This phenomenon would most likely be an example of gene regulation

Inducible

Explanation:

When a gene is expressed only under certain conditions such as the presence of an inducer in the environment to inactivate the repressor, the gene expression is said to be inducible. Here, the presence of substance Y is required as it serves as an inducer by inactivating the repressor protein. When the repressor protein is inactivated, RNA polymerase is able to express the gene. This is an example of inducible gene expression. For example, the presence of lactose is required for the expression of genes of the lac operon.

parasites can detrimentally affect their host, but also must not allow their host to die before they can complete their life cycle. some parasites have complex life cycles with many different hosts, and have had to find ways of persisting in many different environments during the change from one host to another. ectoparasites live outside the body of the host, and can more easily  disperse, but are  more exposed to predators, parasites, parasitoids. endoparasites live inside the body of the host, and are therefore protected from the outside environment. but they can be  attacked by the host's immune system. they have therefore developed  mechanisms for dispersal such as  complex life cycles.

1. loamy sand is about 80% sand with 10% clay and defined mostly by sand particles with some clay to provide structure and fertility. the sand particles are easily visible and the soil holds structure but breaks apart easily.

2. scott sand can improve his soil quality by incorporating more silt and organic matter into the soil. peat moss and organic matter can also be incorporated.