Correct Option
The correct option is A-3, B-4, C-2, D-1
Explanation
The history of cell biology involves a chronological progression of discoveries, starting from the observation of the cell wall to the identification of living components like the nucleus and protoplasm. These milestones laid the foundation for the formulation of the Cell Theory.
Detailed Analysis
- A. Robert Hooke (1665): While examining a thin slice of cork under a self-designed primitive microscope, Hooke observed honeycomb-like structures consisting of many little compartments. He called these boxes "cells". What he actually observed were dead cell walls. This corresponds to 3.
- B. Antonie van Leeuwenhoek (1674): Using an improved microscope, Leeuwenhoek was the first to observe and describe free-living cells (such as bacteria and protozoa) in pond water. This corresponds to 4.
- C. Robert Brown (1831): While studying orchid root cells, Brown discovered a dense, spherical structure within the cell and named it the Nucleus. This discovery established the nucleus as a fundamental component of the cell. This corresponds to 2.
- D. J.E. Purkinje (1839): Purkinje coined the term 'Protoplasm' to describe the fluid, living substance found inside the cell. This corresponds to 1.
Key Takeaway
Robert Hooke is credited with the discovery of cells (cork); Leeuwenhoek discovered the first living cells; Robert Brown discovered the nucleus; and Purkinje coined the term protoplasm.