General terms related to spherical mirrors: A mirror with the shape of a portion cut out of a spherical surface or substance is known as a...
General Terms Related to Spherical Mirrors
April 11, 2024Have you ever wondered who discovered the cell? Or what are cells? Or how are they formed? If you have, then this article about the discovery of cells will provide you with all the information related to cells. A cell is the basic structural and functional unit of all life forms. Moreover, all living things on Earth are made up of one or more cells.
Organisms with a single cell are known as unicellular organisms, such as bacteria. Furthermore, most unicellular organisms are classed as microorganisms. In comparison, organisms with two or more cells are called multicellular organisms, such as plants and animals. The number of cells in plants and animals can vary from species to species. Read on to find more about the discovery of cells.
In 1665, a scientist named Robert Hooke made the first discovery of cells. He was able to discover the cell because of the invention of the microscope. Robert Hooke’s microscope was a recreation of Anton van Leeuwenhoek’s microscope with 300 times magnification. After he invented the microscope, he made numerous observations, and one observation was from very thin slices of a bottle cork.
During Hooke’s observation of thin slices of a bottle cork, he discovered a multitude of tiny pores. He named them cells. The name ‘cell’ came from the Latin word ‘Cella’, meaning ‘a small room’. Furthermore, it resembles cells inhabited by Christian monks in a monastery. The name also came from the word ‘Cellulae’, which meant the six-sided cell of a honeycomb.
Theodor Schwann and Matthias Jakob Schleiden are two scientists who first developed the cell theory in 1839. Although one more scientist named Rudolf Virchow also contributed to the theory. However, his contribution to the theory was not recognised.
Schleiden suggested that every structural part of a plant was made up of cells. In addition, he also suggested that a crystallisation process either within other cells or from the outside made cells. On the other hand, Theodor Schwann states that the structures of animals are also composed of cells. From these conclusions about plant and animal cells, two principles of the cell theory were postulated. They are:
Later in 1855, Rudolf Virchow added the third principle to the cell theory, i.e.,
The modern cell theory includes:
The cell structure is made up of various components. Students can check various components of cells below:
The cell membrane or plasma membrane surrounds the cytoplasm of a cell. The plasma membrane is the outer boundary of an animal cell. However, a cell wall usually covers the cell membrane in plants and prokaryotes. The cell or plasma membrane separates and protects a cell from its surrounding environment.
The Cytoskeleton organise and maintain the shape of cells. It helps in various functions. The Cytoskeleton helps during endocytosis, the uptake of external materials by a cell. It also helps in cytokinesis, the separation of daughter cells after cell division. Furthermore, it moves parts of the cell in growth and mobility processes.
There are two different types of genetic materials, i.e.,
Cells store their long-term information in DNA. Moreover, the DNA sequence of an organism encodes all the biological information contained in that organism.
Cells use RNA to transport information (e.g., mRNA) and enzymatic functions (e.g., ribosomal RNA). Furthermore, cells use transfer RNA (tRNA) molecules to add amino acids during protein translation.
Organelles are parts of the cell and specialised in carrying out one or more vital functions. Similar to human organs like the heart, lung, and kidney, cell organelles perform different functions.
There are two types of cells, namely
Students can get a general idea of the difference between Prokaryotic and Eukaryotic Cells from the table below:
Particulars | Prokaryotic Cells | Eukaryotic Cells |
Size in diameter | 1 to 5 μm | 10 to 100 μm |
Nucleus | No nucleus but have a nucleoid region | True nucleus with double membrane |
Cytoplasmic Structure | Very few structures | Highly structured by endomembranes and a cytoskeleton |
Ribosomes | 50S and 30S | 60S and 40S |
Chromosomes | Single | More than one |
Cell Division | Binary Fission | Mitosis and Meiosis |
Organisms | Usually single cells | Single cells, colonies, higher multicellular organisms with specialised cells |
Examples | Bacteria and Archaea | Plants, Animals, Fungi, Slime Moulds, Protozoa, and Algae |
We hope this detailed article on the Discovery of Cell helps you. If you have any queries regarding this article or the exam, feel to drop a comment below. We will get back to you at the earliest.
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