Discovery of Cells
The discovery of cells began in 1665, when Robert Hooke observed cork under a compound microscope. Later, the work of Schleiden, Schwann, and Virchow led to the cell theory, forming the foundation of modern biology. Subsequent discoveries such as the nucleus, DNA structure, and gene-editing tools like CRISPR revolutionized our understanding of life processes, making this a high-yield topic for NEET Biology.
Who Discovered Cells?
Robert Hooke, an English scientist discovered cells in 1665. Taking a piece of cork and placing it under a very simple microscope that was developed in 1661, Hooke classified the microstructures in it as ‘cells’ since they resembled small monastic living spaces, being small rooms for monks. This introduction of cells made way for further studies to be completed to create cell theory and even the field of modern cellular biology.
Early Discoveries Related to Cells
The early discoveries related to cell are explained below-
Hooke’s first observation
Robert Hooke in 1665 observed the cellular structure using an optimised self-designed compound microscope. He was able to note that the cork was made of many small cavities that were box-like in shape which he referred to as “cells”. As a result of his observations, Hooke paved the way for the subsequent study of living tissues owing to the discovery of a new structural realm that exists out of human sight.
Anton van Leeuwenhoek’s animalcules (1670s)
The simple microscopes were improved in the 1670s by a Dutch tradesman and scientist, Anton van Leeuwenhoek. He also described many kinds of the so-called animalcules found in water, dental plaque, and many other materials. His observations were about bacteria, protozoa, and other monads, thereby enlarging the study of microbiology and giving the first indications of the microbial world as a highly diverse one.
History of Cell Discovery (Timeline Table)
The history of cell discovery is described below:
Year | Scientists | Discovery/Contribution | Description |
1665 | Robert Hooke | First Observation of Cells | Observed and described the small, box-like structures in cork, coining the term "cells." |
1670s | Anton van Leeuwenhoek | Observation of Microorganisms ("Animalcules") | Used handcrafted microscopes to observe and document bacteria, protozoa, and other microorganisms. |
1831 | Robert Brown | Discovery of the Cell Nucleus | Identified and named the nucleus in plant cells, noting its importance in cell function. |
1838-1839 | Matthias Schleiden, Theodor Schwann | Cell Theory | Proposed that all plant and animal tissues are composed of cells, forming the foundation of cell theory. |
1855 | Rudolf Virchow | Omnis cellula e cellula | Proposed that all cells arise from pre-existing cells, solidifying the concept of cell division. |
1902 | Walter Sutton, Theodor Boveri | Chromosome Theory of Inheritance | Demonstrated that chromosomes carry genetic material and follow Mendelian laws of inheritance. |
1953 | James Watson, Francis Crick | Discovery of the DNA Double Helix Structure | Elucidated the structure of DNA, revealing the molecular basis for genetic information in cells. |
2012 | Jennifer Doudna, Emmanuelle Charpentier | Development of CRISPR-Cas9 Gene Editing | Pioneered the CRISPR-Cas9 technology, enabling precise editing of genetic material within cells. |
Discovery of Stem Cells
The discovery is explained below-
Matthias Schleiden and Theodor Schwann (1838-1839)
Schleiden’s Plant Cell Observations: Matthias in 1838, claimed that cells are the structural and functional units of plants and highlighted the importance of the nucleus in the cell and its activities. Schleiden further invested in the study of plant cells and his intense observation formed the basis of appreciating the structural organization of cells in the plant sciences.
Schwann’s Animal Cell Observations: Following Schleiden’s works, Theodor Schwann, a German physiologist, generalized all these observations toward animal tissues. Schwann realized that animal tissues are also made of cells and observed the resemblance with plant cells. This popularised cell theory which says that all living is made up of cells and cells are distinctive units of life.
Rudolf Virchow (1855)
Virchow’s Statement "Omnis cellula e cellula"
In 1855 Rudolf Virchow, a German physician and pathologist formulated that every cell comes from another cell with the famous phrase “Omnis cellula e cellula. ” This was against the theory of spontaneous generation of cells and stressed the process of cell division in growth and reproduction.
Technological Advances in Cell Discovery
The discovery and study of cells became possible due to major technological advancements, especially in microscopy and staining methods.
Compound Microscope
The invention of the compound microscope allowed scientists to view cells at higher magnification using multiple lenses. This advancement enabled the first observations of cell walls by Robert Hooke and laid the foundation for cell theory.
Staining Techniques
Staining methods use special dyes to highlight cell parts, which makes them easy to observe under the microscope. This made it possible to distinguish structures like the nucleus, chromosomes, and organelles.
Electron Microscopy
Electron microscopes use a beam of electrons instead of light, providing extremely high resolution. They revealed detailed structures of organelles such as mitochondria, endoplasmic reticulum, and ribosomes, which were not visible under light microscopes.
Significant Discoveries in Cell Biology
The significant discoveries are explained below-
Discovery of the Nucleus by Robert Brown (1831)
Robert Brown a botanist from Scotland discovered the nucleus in 1831 or as a plant cell organelle. This discovery helped to emphasize the position of the nucleus in the cell, its role in controlling genetic information as well as the activities of the cell.
Contributions of Walter Sutton and Theodor Boveri
It is interesting to note that in the early twentieth century, Walter Sutton and Theodor Boveri postulated that chromosomes are the bearers of hereditary information and that they obey the laws of Mendelian inheritance. Their work showed that during the process of meiosis, chromosomes sort out and distribute to other cells independently. Thus laying a foundation of genetics about chromosomes and the hereditary traits that are associated with them.
Discovery of Mitochondria and Chloroplasts
The discovery of mitochondria and chloroplast are organelles in eukaryotic cells that have distinct functionalities. Mitochondria are responsible for producing ATP through the cellular respiration and chloroplast found in plant cells are involved in photosynthesis. These organelles contain their own genetic makeup to support endosymbiotic theory that deserves them to be symbiotic bacteria.
Discovery of DNA Structure by Watson and Crick (1953)
In 1953, James Watson and Francis Crick formulated the double helix structure of the DNA. The model was able to explain how genetic material is stored inDNA and how this information in the genotype is copied and passed on. This discovery has a tremendous impact for genetics, biotechnology and medicine helping to develop genetic engineering and study genetic diseases.
Cell Culture and Genetic Engineering
Cell culture has formed the basis of in vitro culture systems which have greatly benefited biological and medical research. These techniques are vital in analyses of cellular functions, discovery of drugs and other uses in genetic manipulation. Cell cultures examine the impacts of several stimuli, study diseases and their course, and to manufacture biological goods.
Introduction to CRISPR Technology
The CRISPR-Cas9 system was discovered in the first decade of the 21st century and has created a radical change in genome editing through its efficient technique. This system employs RNA-guided enzymes to cut and alter particular genetic contexts in a living organism. It has untapped capacities in treatment of diseases, food production, and bioengineering.
Impact of Cell Discovery on Science and Medicine
The discovery of cell has made a huge impact on science and medicine:
Understanding Diseases
Cell theory has been the cornerstone towards a higher standing of medical amelioration. Diseases have been considered as cellular disorders and this has led to the formulation of treatment methods. Knowledge about cellular processes has resulted in the development of techniques of diagnosing, treating, and preventing diseases such as cancer, genetic diseases, and diseases in organisms caused by pathogen germs.
Stem Cell Research and Regenerative Medicine
Stem cell research also showed the greater potentiality in the field of regenerative medicine which may be a hope for some diseases such as Parkinson’s disease, spinal cord injuries, and heart diseases. Hence, it is possible to explain why stem cells are so suitable for the replenishment of damaged tissues and organs. Still, this area entails some ethical issues concerning stem cell sources and application.
Discovery of Cells NEET MCQs (With Answers & Explanations)
Important topics for NEET exam are:
Major Discoveries related to Cell
Cell theory
Practice Questions for NEET
Q1. Omnis cellula e cellula is the concept of______given by______
Cell division; Rudolf Virchow
Cell respiration; Meredith Grey
Cell death; Harper Avery
Cell maturation; Leeuwenhoek
Correct answer: 1) Cell division; Rudolf Virchow
Explanation:
In 1838, German botanist Matthias Schleiden observed that all plants are composed of cells, and in 1839, German zoologist Theodor Schwann extended this idea to animals, declaring that they too are made up of cells. These foundational observations led to the formulation of the Cell Theory, which was later refined by German physician Rudolf Virchow, who introduced the famous dictum Omnis cellula e cellula ("new cells arise from pre-existing cells"). The Cell Theory states: (1) All living organisms are made up of one or more cells, (2) Cells are the basic unit of structure and function in organisms, and (3) New cells arise only from pre-existing cells, as they are self-reproducing. This theory remains a cornerstone of modern biology.
Hence the correct answer is option 1) Cell division; Rudolf Virchow
Q2. Which one of the following does not differ in E.coli and Chlamydomonas
Ribosomes
Chromosomes
Cell wall
Cell membrane
Correct answer: 4) Cell membrane
Explanation:
It is semi-permeable and interacts with the outside world. It is PLP (protein lipid-protein). Cell membranes are protine - lipid-protein bilayers which are almost structurally similar in eukaryotes and prokaryotes. The plasma membrane, also known as plasmalemma, regulates the entry and exit of substances, maintaining the cell's internal environment. It consists of a phospholipid bilayer with embedded proteins, allowing selective permeability. Membrane proteins serve various functions, including transport, signalling, and structural support. Despite differences between eukaryotic and prokaryotic cells, the fundamental structure of the plasma membrane is conserved across both, with similar lipid-protein interactions.
Hence, the correct answer is option 4) Cell membrane.
Q3. During development, unspecified cells become cells having unique functions. This process is called :
Evolution
Differentiation
Translation
Replication
Correct answer: 2) Differentiation
Explanation:
Differentiation is the biological process by which unspecialized cells develop into specialized cells with distinct structures and functions. This process enables cells to perform specific roles in the body, leading to the formation of specialized tissues and organs. For example, stem cells differentiate into muscle cells for movement, nerve cells for signal transmission, and red blood cells for oxygen transport. Differentiation is crucial for growth, development, and tissue repair, and is controlled by gene expression, signaling pathways, and environmental factors. As a result, cells, tissues, and organs acquire unique features that enable them to efficiently perform their specific functions.
Hence, the correct answer is option 2) differentiation.
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Frequently Asked Questions (FAQs)
Robert Hooke the English scientist was the one who discovered cell in the year 1665.
It is also worthy to mention Anton van Leeuwenhoek a Dutch Tradesman and scientist who made a lot of contribution to microbiology after he discovered microorganisms in the 1670s.
He observed the cells in cork which he published in a book titled “Micrographia” in that year of 1665. This was the first ever time cells were observed and he referred to them as very small, box shaped structures.
The cell theory was proposed during the mid 1840s by Matthias Schleiden, Theodor Schwann of Munich and Rudolf Virchow. It comprises three main tenet. The cell theory contributed to the advancement of biological sciences by setting out the principle that all forms of life are made of cells hence linking the study of plants, animals and microbes.
In the field of cell biology, technology has however come in and completely revolutionized how cells can be seen and controlled. Examples include development of the compound or the optical microscope, electron microscopy, methods of staining, CRISPR -Cas9.