· Essay # 6. Types of Cells: A multicellular organism is composed of numerous cells. The cells are of three main types undifferentiated (stem cells), differentiated (post-mitotic cells) and dedifferentiated. (a) Undifferentiated or Stem Cells:Estimated Reading Time: 8 mins · Argumentative stem cell essay for best persuasive essay editor service for school An essay on road safety time for action with fractions. The only thing that marks essay cell argumentative stem & Beethoven sonata op 78 analysis essay. They Embryonic Stem Cells Essay Words | 6 Pages. Embryonic cells should be allowed to be used because of the medical benefits they provide. They can be used to cure diseases such as Parkinson’s disease, diabetes, traumatic spinal cord injury, Duchenne’s muscular dystrophy, heart disease, and even vision and hearing loss (blogger.com )
Stem Cell Essay | Cram
In this essay we will discuss about the cell. After reading stem cell essay essay you will learn about: 1. Definition of Cell 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 are made of single cells. They are called unicellular or acellular, e. Amoeba, Chlamydomonas, 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 many cells. A higher animal or plant contains billions of cells, stem cell essay.
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 organisms do not have large 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, stem cell essay, they become specialized for performing different functions.
Human body has some types of cells, e. Cells are grouped into tissues, tissues into organs and organs 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 of 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 functions.
A new cell always develops by division of a pre-existing cell, stem cell essay. 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 is a basic stem cell essay 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 stem cell essay for more than the last stem cell essay 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 stem cell essay various cellular components.
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 stem cell essay 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, stem cell essay, by Malpighiwho called them saccules and utricles. Leeuwenhoek was first to observe, describe and sketch a free living cell.
He observed bacteria, stem cell essay, stem cell essay, spermatozoa, red blood cells, stem cell essay, 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, stem cell essay. Living semifluid substance of cells was discovered by 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, stem cell essay. Development of cell theory illustrates how scientific methodology operates, stem cell essay. 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, stem cell essay.
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 embryos.
He found that animal cells lack a cell wall. Instead they are covered by a membrane, stem cell essay. Otherwise cells of both plants and animals are similar. Schwann defined a 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, stem cell essay. The finding gave cell theory its final shape. Louis Pasteur further proved that stem cell essay originated from life.
Soon Haeckel established that nucleus stores and transmits hereditary traits. Cell theory was modified accordingly. Each cell is made of stem cell essay small mass of protoplasm containing a nucleus in its inside and a plasma stem cell essay 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. Cells are units of function in living organisms, that is, the activities of an organism 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, e.
What are stem cells? - Craig A. Kohn
, time: 4:11Stem Cell Research Persuasive Essay - Pros & Cons Examples
The cons of stem cell research are the use of stem cells and the ethical issues associated with using embryos to harvest cells for research. Another disadvantage of stem cell research is the idea that we as humans are on the verge of playing God by creating life · Essay # 6. Types of Cells: A multicellular organism is composed of numerous cells. The cells are of three main types undifferentiated (stem cells), differentiated (post-mitotic cells) and dedifferentiated. (a) Undifferentiated or Stem Cells:Estimated Reading Time: 8 mins · Stem Cell Research Richard Hamilton. Words: Length: 2 Pages Document Type: Essay Paper #: Read Full Paper. ichard Hamilton (), says that the embryo cells are very important because they can grow into any organ which can help to solve the increased need of organs for transplant in America
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