Which statement is part of the cell theory?

The 3 parts, or tenets, of cell theory are a little outdated in terms of modern biology, but still serve as a good general model. The three tenets of cell theory are discussed in detail below.

1. All organisms are made of cells

Cells are the smallest unit of life. Each cell is a membrane of semi-permeable phospholipids wrapped around cytosol or a solution of water and dissolved solutes. All cells rely on DNA to hold the information necessary to produce the molecules they use to obtain energy. Although the methods for obtaining energy vary widely, all organism obtain energy to grow and reproduce. This first tenet of the cell theory is mostly true, but the discovery of viruses lead to complications. Viruses, while they use DNA or RNA to reproduce, do not have cells or cellular membranes. Viruses typically use a host cell to replicate. In this case, the virus appears to be living, but does not create its own cell. Some scientist argue that viruses are not living, thus cell theory is not violated.

2. Cells are the most fundamental unit of life

Organisms can be single cells, which hold all of the components necessary for a metabolism, or they can be more complex. More complex organisms divide the various metabolic tasks into different groups of cells, called tissues. These tissues are arranged in compartments with membranes that separate them from other tissues. These groups of tissues are called organs. A group of organs functioning together is an organism, or an individual creature. Each cell is distinct from the cells next to it, and each functions independently, while contributing to the output of the organism as a whole. Again, modern cell theory is a bit more complicated because advances in science have revealed many different organelles within cells. These organelles are bound in membranes themselves, and serve different functions for eukaryotic cells. Some scientists argue that these are more fundamental units, but other scientists argue that like an organ outside of an organism, they could not function without the cell.

3. Cells come from other cells

As far as we know, no cell on Earth currently has arisen spontaneously. All cells are the result of cell division. When a cell is large enough, it replicates its DNA and important components. These components can then be divided into two daughter cells, which are copies of each other. Variations in the DNA in each cell can lead to changes in how they function, which can result in them dividing at different rates. The cell that reproduces more than the other cell will pass on more of its DNA. The purpose of every cell or organism is to reproduce the DNA in cells.
This third tenet of the cell theory has yet to be disproven. No scientist has ever created a functioning cell without replicating another cell, although some scientists are trying. If they were successful, it would give proof to how life could have evolved. It is thought that a self-replicating molecule mutated, developed the ability to produce a membrane, and thus the first cell was born. The cell was such a successful form of life that all life since has used the same basic template.

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Biologydictionary.net Editors. "Three Parts of Cell Theory." Biology Dictionary, Biologydictionary.net, 13 Apr. 2019, https://biologydictionary.net/three-parts-of-cell-theory/.

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Biologydictionary.net Editors. "Three Parts of Cell Theory." Biology Dictionary. Biologydictionary.net, April 13, 2019. https://biologydictionary.net/three-parts-of-cell-theory/.

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The Elements of Life

In biology, the elements of life are the essential building blocks that make up living things. They are carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. The first four of these are the most important, as they are used to construct the molecules that are necessary to make up living cells. These elements form the basic building blocks of the major macromolecules of life, including carbohydrates, lipids, nucleic acids and proteins. Carbon is an important element for all living organisms, as it is used to construct the basic building blocks of life, such as carbohydrates, lipids, and nucleic acids. Even the cell membranes are made of proteins. Carbon is also used to construct the energy-rich molecules adenosine triphosphate (ATP) and guanosine triphosphate (GTP). Hydrogen is used to construct the molecules water and organic compounds with carbon. Hydrogen is also used to construct ATP and GTP. Nitrogen is used to construct the basic building blocks of life, such as amino acids, nucleic acids, and proteins. It is also used to construct ATP and GTP. Oxygen is used to construct the basic building blocks of life, such as carbohydrates, lipids, and nucleic acids. It is also used to construct ATP and GTP. Phosphorus is used to construct the basic building blocks of life, such as carbohydrates, lipids, and nucleic acids.

Which statement is part of the cell theory quizlet?

What are 3 parts of the cell theory?