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What are the three parts of the cell theory?

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The three parts of the cell theory are as follows: (1) All living things are made up of cells, (2) Cells are the smallest units (or most basic building blocks) of life, and (3) All cells come from preexisting cells through the process of cell division. Cells were first observed by the natural philosopher Robert Hooke in 1665. Though many scientists contributed to the understanding of cells, Matthias Schleiden and Theodor Schwann are credited with describing the first two parts of the cell theory in 1839, and Rudolf Virchow with later contributing the third. Today, the cell theory is considered the foundation of biology.

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The cell theory is an explanation of what cells are and why they exist.  The three main parts are:  1) All living things are made of cells and their products,  2) New cells are created by old cells dividing into two, and  3) Cells are the basic building units of life.  In 1665, Robert Hooke observed, with the aid of a crude compound microsope, the structure of a thin slice of cork.  The structure resembled stacks of hat boxes, or holding cells, so he called what he observed "cells".  In 1674, Anton von Leeuenhoek observed, in a sample of pond water, small animal-like creatures swimming around.  He probably was looking at Spyrogira, but he called these small organisms "animal-cules".  Theodore Schwann and Matthias Schleiden are responsible for formulating the first two parts of the cell theory, which was a scientific explanation of what these scientists had observed up to this point.  A few years later, Rudolph Virchow added the third part of the cell theory, that all things are composed of these basic building blocks called cells.

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The cell theory was arrived at after much study of living cells due to the intellectual contributions of Matthias Schleiden who noted all plants contains cells, and in 1838 added that different parts of plants were composed of cells.  Theodor Schwann noted all living things contained cells and cell products and Rudolph Virchow, who noted that cells come from pre-existing cells. He pusblished his work in 1858 which rejected the idea of spontaneous generation, which was believed at the time. The cell theory states that 1. cells are the unit of structure of all living things 2. cells are the unit of function of living things--they carry out life processes 3. all cells come from pre--existing cells. These three scientists are credited with arriving at the cell theory. However, one cannot discount other contributers--the famous Francesco Redi experiment that proved maggots didn't come from rotten meat, but from adult lies laying eggs and the vast and detailed drawings by Anton Leeuwenhoek, who saw the cells of various living things using his early microscopes.

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What are the three statements of the cell theory?

The three basic tenets of the cell theory are:

1.) All living things are made of cells

2.) Cells are the smallest structural and functional unit of living organisms

3.) All cells come from preexisting cells.

The first is self-explanatory, as all living things - from microscopic organisms to the largest whale - are made of cells.  These cells can vary widely, but all living things are composed of cells.

Secondly, living organisms cannot be broken down any farther than the cell level. Like atoms and matter (atoms are the smallest units of matter), cells and living organisms are related: living organisms, at their most basic level, are made of cells.

Finally, no cell comes about in a vacuum.  All cells on the planet came from other cells. Cells divide by a number of mechanisms, such as mitosis (non-sexual cell division) and meiosis (sexual cell division), but every cell in existence came from another cell.

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What are the three statements of the cell theory?

The three statements or tenets of the cell theory are:

  1. All living beings are made up of cells.
  2. Cell is the most basic unit of life.
  3. All cells must come from pre-existing cells.

The first statement refers to the fact that all the life forms present on this planet are composed of one or more cells. The simplest life forms are unicellular, that is are made up on single cells; whereas the higher life forms (human beings, trees, etc.) are multicellular (composed of many cells). The second tenet refers to the idea that cells can carry out all the functions required for life propagation including, reproduction, maintenance, growth, metabolism, etc. And the third tenet refers to the reproduction of cells from parent cell or cells. It means that cells are born from existing cells and that's how life propagates. 

Hope this helps

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State the three parts to cell theory.

The three parts to the cell theory are as follows:

  1. All living things are composed of cells.
  2. All cells come from preexisting cells.
  3. Cells are the basic unit of structure and function of living things. In other words, cells are the most basic building blocks of life.

The cell theory resulted from the work of several different scientists spread over the course of years.  Matthias Schleiden stated in 1838 that all plants are made of cells, and a year later Theodor Schwann said that all animals are made of cells.  In 1855, Rudolf Virchow stated that all cells arise from the division of preexisting cells.  This discovery put an end to the previous thinking that cells simply came about through spontaneous generation.  It is from their work and observations that we get the cell theory.  

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What are the three main parts of cell theory?

The cell theory is a scientific theory that defines the characteristics that all cells should manifest. Cells were first discovered by Robert Hooke in the 17th century. Matthias Schleiden, Theodor Schwann, and Rudolf Virchow are also accredited with being contributors towards the cell theory. 

The tree main parts of the cell theory are:

1. All living things are made of one or more cells (so, if the thing is not made of cells, then it is considered to be non-living).

2. The cell is the smallest unit of life

For example, parts of cells called organelles are not considered living. Nor are viruses because they are not made of cells. 

3. All cells come from other cells. In other words, "life comes from life". You cannot get something living from something that is non-living. 

This is known as biogenesis. It is in opposition to spontaneous generation. 

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What are the three important ideas in cell theory? 

In order to look at the three important ideas of cell theory, one must first understand what cell theory is. Cell theory was purposed by Theodor Schwann and Matthias Schleiden in 1838. Amazingly, cell theory still holds true today as the principle that drives all of cell biology. The three main and most important ideas of cell theory are:

1) All living things are made from one or more cells.

2) Cells can only come from pre-existing cells.

3) A cell is the smallest form of life.

Interestingly, there are a few examples of organelles, such as mitochondria in animal cells and chloroplasts in plant cells, that are self-replicating, but are considered an exception to cell theory because they replicate within the cell that they reside in. Hope this helps!

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