Final answer:
In drug discovery, in vitro model systems are used to study the absorption, distribution, and metabolism of new chemical entities. They allow researchers to investigate specific biological phenomena and gain understanding that can be applied to other species. Examples of in vitro model systems include cell cultures, tissue explants, and organoids.
Step-by-step explanation:
In the field of drug discovery, in vitro model systems are used to study the absorption, distribution, and metabolism of new chemical entities. These model systems are species or biological systems that are used to investigate specific biological phenomena and gain understanding that can be applied to other species. Examples of in vitro model systems include cell cultures, tissue explants, and organoids. These model systems allow researchers to study the effects of drugs on biological processes in a controlled environment before testing them in animal or human subjects.