Now that we’ve gone over the nine basic properties of the cell as given by Karp, I will continue by providing more features of cells on Earth, as given by another molecular cell biology text. This time, however, the discussion will be a bit more in-depth. Personally, I think that both authors’ views on this point are important to know. There will be some overlap, but much of the information is original and worth your time. And it is worth noting that unlike chemistry textbooks, many biology textbooks seem to take differing approaches when introducing and explaining a topic (whereas on the other hand, the chemistry textbooks I review tend to contain the same information, with some explanations much more detailed than others.)
To begin, without having to read a science textbook, we could all agree that heredity is central to the definition of life, even if it is difficult to define life. Many other nonliving things that are created daily, which don’t share the link that parents do with their offspring. For example, the manufacturing of thousands of cars that are alike does not require the same link that producing offspring does. Moreover, life uses the free energy that is required to maintain the organization of cells in order to drive a system of chemical processes for which the instructions are provided by hereditary information. You’ll note that this concept is strikingly similar to the cell property we discussed, that cells are complex and organized (Alberts et al. 2014).
Though many organisms are single-celled, the human body contains an incredible 1013 cells. Despite this very large number, the entirety of the organism was generated from a single cell, which underwent a number of divisions afterwards. That a single cell is the precursor to life is true of all organisms in the world. And thus, that single cell serves as a vehicle for the hereditary information that serves to define each and every species on the planet. As we discussed previously as another property of cells, cells are able to reproduce, and thus contain all of the machinery to do this (Alberts et al. 2014).
The first universal feature of cells as described Alberts et al. is as follows:
Since the development over time of computers as a form of modern technology, we as humans have become familiar with the measurement of information in units of bytes, for example. Technologies that were once used to store different types of information (such as DVDs for movies) are becoming obsolete over time, as well. Information is stored for cells in a way that is analogous to the way that computers store information. For cells, information is stored in DNA, which appears as double-stranded molecules that are long, unbranched, paired polymer chains, always formed as the same four types of monomers. These monomers are termed adenine, guanine, cytosine, and thymine, and are usually represented as A, G, C, and T, respectively. A, G, C, and T are strung together in a sequence that is long and linear, and which encodes genetic information about an organism. Going back to our earlier analogy, this is similar to how 1s and 0s are used in a sequence in order to encode information in a computer file. Due to the fantastic scientific discovery of this information, scientists have been successful at placing a bit of human DNA into a bacterial cell, and vice versa (placing a bit of bacterial DNA into a human cell), and having it read, interpreted, and copied. Through scientific discovery, as well, scientists have been able to read complete sequences of monomers in any given DNA molecule, which can span millions of nucleotides. This allows them to interpret the hereditary information stored within the DNA for an organism (Alberts et al. 2014).
As you might realize, this is very similar to one of Karp's properties of cells: That cells have a genetic program that they are capable of using. Granted, this explanation was a bit more detailed, and this is the focus that we will be taking in future discussions of molecular cell biology.
A prospective medical student, looking to help others succeed.