nellorganismo

Nell'organismo is the Italian phrase used to indicate that a process or observation occurs within a living organism. In English, the closest equivalent is in vivo. The form nell'organismo—note the apostrophe—is the standard Italian orthography; the uncontracted form nellorganismo appears in some nonstandard texts.

Usage and scope: The expression is used across biology and medicine to describe systemic phenomena or measurements that take place inside the whole organism, rather than outside it or in isolated tissues. It is typically contrasted with in vitro (outside the organism, in a laboratory setting) and with ex vivo (using tissues taken from the organism but studied outside the living body).

Applications: In pharmacology, pharmacokinetics and pharmacodynamics refer to how a drug is absorbed, distributed, metabolized, and eliminated within the organism, and how it exerts its effects. In physiology and pathology, processes such as metabolism, homeostasis, immune responses, and hormonal signaling are described as occurring nell'organismo. In scientific writing, the term signals that observations reflect whole-organism biology rather than cellular or in vitro contexts. The concept aligns closely with the English term in vivo.

See also: in vivo, physiology, pharmacology, in vitro, ex vivo, metabolism, homeostasis.