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The cell was first discovered by Robert Hooke in 1665 using a microscope. The first cell theory is credited to the work of Theodor Schwann and Matthias Jakob Schleiden in the 1830s. In this theory the internal contents of cells were called protoplasm and described as a jelly-like
Evolution of cells refers to the evolutionary origin and subsequent evolutionary development of cells. Cells first emerged at least 3.8 billion years ago [1] [2] [3] approximately 750 million years after Earth was formed. [4]
The cell retains a dual existence as a distinct entity and a building block in the construction of organisms. [32] By the 1860s, these tenets were the accepted basis of cell theory, used to describe the elementary anatomical composition of plants and animals. [3] Schwann's theory and observations created a foundation for modern histology. [3]
The cell is the basic structural and functional unit of all forms of life. Every cell consists of cytoplasm enclosed within a membrane; many cells contain organelles, each with a specific function. The term comes from the Latin word cellula meaning 'small room'. Most cells are only visible under a microscope.
He was also the first to document microscopic observations of muscle fibers, bacteria, spermatozoa, red blood cells, crystals in gouty tophi, and among the first to see blood flow in capillaries. Although Van Leeuwenhoek did not write any books, he described his discoveries in chaotic letters to the Royal Society , which published many of his ...
The frontispiece to Erasmus Darwin's evolution -themed poem The Temple of Nature shows a goddess pulling back the veil from nature (in the person of Artemis). Allegory and metaphor have often played an important role in the history of biology. Part of a series on Biology Index Outline Glossary History (timeline) Key components Cell theory Ecosystem Evolution Phylogeny Properties of life ...
The researchers claimed in 2015 that the leaf-like cells generated 47 percent more electricity than those without folds. Image credits: Sasha Weilbaker #8 Self-Cleaning Paint
He recognized under the name of primordial utricle the protoplasmic lining of the vacuolated cell, and first described the behaviour of the protoplasm in cell division. These and other observations led to the overthrow of Schleiden's theory of origin of cells by free-cell-formation. His contributions to knowledge of the cell-wall were no less ...