The discussion revolves around the distribution of carbon isotopes in the human body, their potential mutagenic effects, and their role in DNA diversity. Participants explore the presence of naturally occurring radioactive isotopes, their concentrations, and the implications of these isotopes on biological processes.
Participants express multiple competing views regarding the role and behavior of isotopes in biological systems, with no consensus reached on the implications of these isotopes for DNA diversity or their chemical behavior.
There are unresolved questions about the specific concentrations of isotopes in different body tissues and the conditions under which isotopes might affect biological processes. Some claims rely on assumptions about radiation exposure and its effects.
Small traces of many naturally occurring radioactive materials are present in the human body. These come mainly from naturally occurring radioactive nuclides present in the food we eat and in the air we breathe. These isotopes include tritium (3H), carbon-14 (14C), and potassium-40 (40K). About 11% (40 mrem) of our radiation dose comes from naturally occurring radioactive materials in the body. Most of the dose comes from a radioactive isotope of potassium. Radioactive potassium-40, as well as other radioactive materials (such as carbon-14) which occur naturally in air, water, and soil, are incorporated into the food we eat and then into our body tissues.
Loren Booda said:Are different carbon, e. g., isotopes distributed throughout the human body in relatively different concentrations?
Loren Booda said:Are radioactive atoms mutagenic and electronically dissimiliar, thus affecting the chemistry of neighboring structures?
Loren Booda said:Could these isotopes be a considerable source of DNA diversity?
For instance, in the evolution of grasses first one isotope of carbon (designated C3) was common, then another (C4). I thought that different isotopes in general might perform different functions in human tissue or DNA as well.What do you mean by this? If different isotopes are in different concentrations in different places in the body? Can you please clarify?
Loren Booda said:MattaraFor instance, in the evolution of grasses first one isotope of carbon (designated C3) was common, then another (C4). I thought that different isotopes in general might perform different functions in human tissue or DNA as well.
Plus, different isotopes are chemically identical, that is, a radioactive C14 atom is no different for chemical reactions than a non-radioactive carbon atom. Chemical behavior is determined primarily by the electrons in the outer shell, which is why elements are divided into periods.Loren Booda said:MattaraFor instance, in the evolution of grasses first one isotope of carbon (designated C3) was common, then another (C4). I thought that different isotopes in general might perform different functions in human tissue or DNA as well.
Loren Booda said:MattaraFor instance, in the evolution of grasses first one isotope of carbon (designated C3) was common, then another (C4). I thought that different isotopes in general might perform different functions in human tissue or DNA as well.
The chemical properties should be identical. The thing that contributes to their difference is that Deuterium has a larger mass so, for example, reactions involving Deuterium might proceed at a slower rate than those involving Hydrogen.Loren Booda said:If you all have the opportunity, see the bottom half of page 230 in the popular (and scientific) book "Beasts of Eden," about mammal evolution. Its author, David Rains Wallace, seems to have made a major gaffe with the term "isotope" in reference to carbon in grasses.
Aside: I believe that deuterium may have significant chemical differences with common hydrogen.