In the history of biology, through which type of light microscope were cells first observed and described by Robert Hooke in the 17th century?

Introduction / Context:
The discovery of cells is a landmark event in the history of science. In the 17th century, the English scientist Robert Hooke examined thin slices of cork using an early microscope and observed tiny box-like structures, which he called “cells.” Knowing what kind of microscope he used helps students connect the development of optical instruments with major discoveries in biology. This question focuses on whether Hooke used a simple single-lens device or a more complex compound microscope.

Given Data / Assumptions:

• The question asks specifically about the type of microscope used for the first observation of cells.
• Robert Hooke published his observations in his book "Micrographia" in 1665.
• Options include a compound light microscope, a simple microscope, an electron microscope, and a scanning tunnelling microscope.
• We assume basic knowledge of the timeline of scientific inventions.

Concept / Approach:
A simple microscope uses a single lens, similar to a magnifying glass. A compound microscope, on the other hand, uses two or more lenses (for example, objective and eyepiece) to achieve higher magnification and better image clarity. Robert Hooke worked with early compound microscopes that were relatively crude by today's standards but still used multiple lenses. Electron microscopes and scanning tunnelling microscopes were developed centuries later in the 20th century and are far too advanced for Hooke's time. Therefore, the correct answer is that cells were first observed through a compound light microscope.

Step-by-Step Solution:
Step 1: Recall that Robert Hooke's observations occurred in the 1600s, long before the invention of electron or scanning tunnelling microscopes. Step 2: Understand that early scientists developed microscopes with multiple lenses to increase magnification; these are called compound microscopes. Step 3: Note that Hooke's “Micrographia” illustrations show detailed views of cork cells and insects, requiring more magnification than a simple hand lens typically provided at that time. Step 4: Recognise that simple microscopes, like those used by Antonie van Leeuwenhoek, also played a role in early microbiology but were different from Hooke's instrument. Step 5: Eliminate options that mention electron or scanning tunnelling microscopes, since these did not exist in the 17th century. Step 6: Conclude that Hooke used a compound light microscope to first observe cells.

Verification / Alternative check:
Historical accounts of microscopy describe Hooke's instrument as an early compound microscope with multiple lenses. Diagrams of his device show an objective lens close to the specimen and an eyepiece lens through which the observer looks, along with illumination from a candle or sunlight and a focusing mechanism. In contrast, electron microscopes use vacuum systems and electron beams, technologies that emerged only in the 20th century. Scanning tunnelling microscopes belong to the field of nanotechnology and allow imaging of individual atoms, which is far beyond the capabilities of 17th century technology. These facts confirm the classification of Hooke's microscope as a compound light microscope.

Why Other Options Are Wrong:
A simple microscope with only a single lens describes instruments like those used by van Leeuwenhoek, not Hooke's compound instrument for observing cork cells.
An electron microscope using beams of electrons instead of light was invented in the 20th century and could not have been used by Hooke.
A scanning tunnelling microscope for imaging individual atoms is a highly advanced modern instrument and is unrelated to the 17th-century discovery of cells.

Common Pitfalls:
Students sometimes confuse the contributions of Hooke and van Leeuwenhoek because both were pioneers in microscopy. While van Leeuwenhoek used powerful simple microscopes to study bacteria and protozoa, Hooke's famous cork cell observations were made with a compound microscope. A helpful memory trick is to remember “Hooke's book, Micrographia, and his compound microscope,” linking his name with the more complex instrument. Keeping the historical timeline in mind prevents confusion with much later inventions like electron microscopes.

Final Answer:
Cells were first observed and described by Robert Hooke using A compound light microscope using more than one lens.