AP BIOLOGY

Detailed explanation-1: -Robert Hooke discovered cell in the year 1665. He observed cork cell in the bark of Spanish oak tree under a simple microscope and was able to see the empty structures surrounded by walls and named it a cell. He elucidated his observation in a book called “Micrographia".

Detailed explanation-2: -His microscope used three lenses and a stage light, which illuminated and enlarged the specimens. These advancements allowed Hooke to see something wondrous when he placed a piece of cork under the microscope. Hooke detailed his observations of this tiny and previously unseen world in his book, Micrographia.

Detailed explanation-3: -The invention of the microscope led to the discovery of the cell by Hooke. While looking at cork, Hooke observed box-shaped structures, which he called “cells” as they reminded him of the cells, or rooms, in monasteries. This discovery led to the development of the classical cell theory.

Detailed explanation-4: -These structures were empty air-filled chambers. Robert Hooke named these empty chambers the cell or pore. He concluded that due to the presence of air in the structure made the cork floatable and springy. So the correct answer is option B.

Detailed explanation-5: -While observing cork through his microscope, Hooke saw tiny boxlike cavities, which he illustrated and described as cells. He had discovered plant cells! Hooke’s discovery led to the understanding of cells as the smallest units of life-the foundation of cell theory.