Who was the first to observe "small chambers" in cork and call them cells?

The individual who first observed "small chambers" in cork and referred to them as cells was Robert Hooke. This significant observation took place in the 17th century when Hooke used a microscope to examine thin slices of cork. He noticed the small, box-like structures that reminded him of the monks' cells in a monastery, hence coining the term "cells." This discovery laid the foundation for cell theory, which became a fundamental concept in biology.

Hooke's work is particularly important because it was one of the earliest examples of using microscopy to study biological materials, prompting further investigations into the structures that make up living organisms. The term "cell" has since evolved to represent a wide array of functional units in biology, but Hooke's initial naming introduced the concept that cells are the basic building blocks of life.