Cell Structure - Cell Organelles 1. What is cell theory? Cell theory asserts that the cell is the constituent unit of living beings. Before the discovery of the cell‚ it was not recognized that living beings were made of building blocks like cells. The cell theory is one of the basic theories of Biology. 2. Are there living beings without cells? Viruses are considered the only living beings that do not have cells. Viruses are constituted by genetic material (DNA or RNA) enwrapped by a protein
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biology‚ cell theory is a scientific theory that describes the properties of cells‚ which are the basic unit of structure in all organisms and also the basic unit of reproduction. The initial development of the theory‚ during the mid-17th century‚ was made possible by advances in microscopy; the study of cells is called cell biology. Cell theory is one of the foundations of biology.The observations of Hooke‚ Leeuwenhoek‚ Schleiden‚ Schwann‚ Virchow‚ and others led to the development of the cell theory
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Cell Theory In biology‚ cell theory is a scientific theory that describes the properties of cells‚ the basic unit of structure in every living thing. The initial development of the theory‚ during the mid-17th century‚ was made possible by advances in microscopy; the study of cells is called cell biology. Cell theory states that new cells are formed from pre-existing cells‚ and that the cell is a fundamental unit of structure‚ function and organization in all living organisms. It is one of the
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Portfolio The Cell and Cell Theory [pic] The cell The word cell comes from the Latin word “cellula”‚ which means a small room. The cell is the smallest unit of a living organism‚ also known as “the building block of life”. Every living organism is consisted of a cell. There are bacteria (unicellular organisms)‚ and multicellular organisms. There are different types of cells‚ prokaryotic and eukaryotic cells. All cells come from preexisting cells. “Every cell is self-maintaining;
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The Cell Theory The Cell Theory‚ formed by Anton van Leeuwenhoek‚ Robert Hooke‚ Matthias Schleiden‚ Theodore Schwann‚ and Rudolf Virchow‚ refers to the idea that cells are the basic unit of structure in every living organism. The theory justifies three principles: all living organisms are composed of one or more cells; the cell is the most basic unit of structure‚ function‚ and organization in all organisms; and all cells come from pre-existing‚ living cells. The formation of the cell theory started
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The CELL THEORY‚ or cell doctrine‚ states that all organisms are composed of similar units of organization‚ called cells. The concept was formally articulated in 1839 by Schleiden & Schwann and has remained as the foundation of modern biology. The idea predates other great paradigms of biology including Darwin’s theory of evolution (1859)‚ Mendel’s laws of inheritance (1865)‚ and the establishment of comparative biochemistry (1940). Ultrastructural research and modern molecular biology have
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background knowledge relating to the current cell theory‚ the differences between prokaryotes and eukaryotes‚ and the structures and functions found within cells. Once this knowledge is known‚ a person is then able to give their opinion in the debate. In the 1800s‚ the cell theory was developed. This theory states that cells are found in all living things making them the basic units of life and that all cells come from other cells. In order to be classified as a cell‚ the object in question must be able
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Weismann‚ who noted that two cell divisions were necessary to transform one diploid cell into four haploid cells if the number of chromosomes had to be maintained. In 1911 the American geneticist Thomas Hunt Morgan observed crossover in Drosophila melanogaster meiosis and provided the first genetic evidence that genes are transmitted on chromosomes. The term meiosis was introduced to biology by J.B. Farmer and J.E.S. Moore in 1905 Meiosis i/maɪˈoʊsɨs/ is a special type of cell division necessary for
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CELL THEORY – STEM CELLS Stem cells are a large focus of study in today’s biomedical world. “They are cells that exist in an undifferentiated state‚ and transform into differing tissue types depending on what the cells surrounding them are‚“ (National Institute of Health‚ 2012). Stem cells have the remarkable potential to develop into many different cell types in the body during early life and growth. In addition‚ they also serve as an internal repair mechanism inside many tissues‚ dividing without
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Question 1 1 out of 1 points Items that are necessary for survival are called Answer Selected Answer: needs Correct Answer: needs Question 2 1 out of 1 points Materials that come from nature such as water‚ coal and timber are examples of Answer Selected Answer: natural resources Correct Answer: natural resources Question 3 0 out of 1 points The economy of the United States is often described as Answer
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