1. Essay on the Introduction to Cell: The cell is the basic unit of life. The life of all organisms including man starts from a single cell and the body is a consortium of individual cells of specific functions and features working in a coordinated manner. Each cell is an amazing world of several biochemical activities- it can assimilate Estimated Reading Time: 8 mins Dec 14, · Cell Structure Cell Structure. Cellular Metabolism. Cell Growth and Division 1) Cell structure. The cell is the basic element of life, as we understand it. All cells are built up essentially similarly. The cell must have a cell membrane that borders this element of Estimated Reading Time: 6 mins Flag this paper! Cells, the building blocks of the human body, contain genetic information (DNA) that is passed on from parent cell to daughter cell through the cell reproduction process called cell division. When a cell divides the genetic information contained in DNA copies itself and transmits to a daughter cell through a series of processes. There are two types of cells: /5(7)
FREE Cell Essay Essay
In this essay we will discuss about the cell. After reading this essay you will learn about: 1. Definition of Cell essay 2. Discovery of Cell 3. Cell Theory 4. Modern Cell Theory 5. Limit of Cell Size or Volume 6. Types 7. Compartmentalization for Cellular Life 8. Cell— An Open System 9. Shapes Essay 1. Cell is a basic unit of life as no living organism can have life without being cellular because cell is a unit of both its structure and function. All life begins as a single cell. A number of organisms cell essay made of single cells, cell essay.
They are called unicellular or acellular, e. Amoeba, Chlamydomonas, cell essay, Acetabularia, bacteria, yeast. Anything less than a complete cell cans neither lead an independent existence nor perform all the functions of life. A multicellular organism is made of cell essay cells. A higher animal or plant contains billions of cells. For example, a newly born human infant has 2 x cells. The number increases to trillion x or cells in the body of 60 kg human being. A drop of blood contains several million cells. The large sized cell essay do not have cell essay sized cells. Instead they possess higher number of cells. In multicellular organisms, cells are building blocks of the body or basic units of body structure.
Of course, they become specialized for performing different functions. Human body has some types of cells, e. Cells are grouped into tissues, tissues into organs and cell essay into organ systems. Occurrence of different types of tissues, organs and organ system results in division of labour or performance of different functions of the body by specialised structures. Cells are not only the building blocks of the organisms, they are also the functional units of life. Life passes from one generation to the next in the form of cells. The activities cell essay an organism are actually the sum total of activities of its cells. Each cell of the body possesses the same genetic information though mature cells may become specialized to perform specific cell essay. A new cell always develops by division of a pre-existing cell.
Cells are totipotent, i. Internally each cell is build up of several organelles. The organelles perform different functions just like the ones carried on by different organ systems of the body. All life activities of the organism are present in miniature form in each and every cell of its body. Thus, cell essay, cell is a basic unit of life and structural and functional unit of an organism. It is the smallest unit capable of independent existence and performing the essential functions of life. Essay 2.
Work on the study of cell has continued for more than the last three and a half centuries. It required microscopes or instruments with good resolving power and magnification. Techniques like preservation, sectioning, staining and mounting were needed to distinguish various cellular components, cell essay. Improvement in tools and techniques has continued all this period to enhance our knowledge about the cell. The first microscope was built by Zacharias Janssen in It was first modified by Galileo and then by Robert Hooke Fig.
Robert Hooke was a mathematician and physicist. He developed a new microscope with which he studied the internal structure of a number of plants. His work is famous for the study of cork cells. He took a piece of cork of spanish oak and prepared thin slice by means of sharp pen knife. A deep planoconcave lens was used for throwing light on cork piece. The latter was observed under the microscope. The piece of cork was found to have a honey comb structure with a number of boxes like compartments, each having a pore and separated from others by diaphragms Fig. Robert Hooke named the compartments as cellulae singular- cellula now known as cells Latin cella — hollow spaces or compartments. He did not know the significance of these structures and regarded them as passages for conducting fluids.
Robert Hooke found that the cells or boxes were not very deep. A cubic inch contained , cells, a square inch 1, 66, and one inch strip cells. Cells were also observed prior to Hooke, by Malpighicell essay, who cell essay them saccules and utricles. Leeuwenhoek was first to observe, describe and sketch a free living cell. He observed bacteria, cell essay, protozoa, spermatozoa, cell essay, red blood cells, etc. In the beginning of nineteenth century it became clear that the bodies of organisms are made of one or more cells. Robert Brown discovered the presence of nucleus in the cells of orchid root.
Living cell essay substance of cells was discovered cell essay Dujardin and named sarcode. Schleiden found all plant cells to have similar structure— cell wall, a clear jelly-like substance and a nucleus. Schwann discovered that animal cells lacked cell wall. Purkinje and von Mohlrenamed sarcode or the jelly like substance of the cells as protoplasm Gk. protos- first, plasma- form. Cell membrane was discovered by Schwann but was provided with a name by Nageli and Cramer Soon various organelles were discovered inside the cells. Electron microscope has elaborated our knowledge about cells. Essay 3. Development of cell theory illustrates how scientific methodology operates.
It involves observation, hypothesis, formulation of theory and its modification. Observations were started by Malthias Schleidena German botanist who examined a large number of plant tissues. He found that all plant tissues were made of one or the other kind of cells. Therefore, he concluded that cells constitute the ultimate units of all plant tissues. Theodore Schwanna German Zoologist, studied different types of animal tissues including development of cell essay. He found that animal cells lack a cell wall. Instead they are covered by a membrane. Otherwise cells of both plants and animals are similar, cell essay.
Schwann defined cell essay cell as membrane en-locked, nucleus containing structure. He also proposed a cell hypothesis — bodies of animals and plants are made of cells and their products. The theory proposed that cells are the units of both structure and function of organisms. Rudolf Virchow observed that hew cells develop by division of the pre-existing cells— Omnis cellula e cellula theory of cell lineage or common ancestry, cell essay. The finding gave cell theory its final shape, cell essay. Louis Pasteur further proved that life originated cell essay life. Soon Haeckel established that nucleus stores and transmits hereditary traits. Cell theory was modified accordingly. Cell essay cell is made of a small mass of protoplasm containing a nucleus in its inside and a plasma membrane with or without a cell wall on its outside.
Activities of an organism are the sum total of activities and interactions of its constituent cells. Essay 4. Modern Cell Theory : It is also known as cell doctrine or cell principle. Cells are units of structure in the body of living organisms. Every cell is made up of a mass of protoplasm having a nucleus, organelles and a covering membrane, cell essay. Cells are units of function in living organisms, that is, cell essay, the activities of an cell essay are the sum total of the activities of its cells. The cells belonging to diverse organisms and different regions of the same organism have a fundamental similarity in their structure, chemical composition and metabolism.
Depending upon specific requirement, the cells get modified, cell essay, e.
The Cell Theory - Complete Breakdown in 8 Minutes - Bio 101 - STEMstream
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Read this Essay on Cells in Human Body! The body of any living organism is made up of cells. Cells are very minute in size and extremely complicated in structure. Human is no exception. Each cell is basically a unit of protoplasm, which is said to be the “material basis of life”. The protoplasm is the combination of cytoplasm and nucleus Essay Contents: Essay on the Definition of Cell Essay on the Discovery of Cell Essay on the Cell Theory Essay on the Modern Cell Theory Essay on the Limit of Cell Size or Volume Essay on the Types of Cells Essay on Compartmentalization for Cellular Life Essay on Cell— An Open System Essay on the Estimated Reading Time: 8 mins 1. Essay on the Introduction to Cell: The cell is the basic unit of life. The life of all organisms including man starts from a single cell and the body is a consortium of individual cells of specific functions and features working in a coordinated manner. Each cell is an amazing world of several biochemical activities- it can assimilate Estimated Reading Time: 8 mins
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