Radioactive Isotopes of Various Elements Can Be Used to Label

question 28

Essay

Radioactive isotopes of various elements can be used to label molecules for use in studies of metabolic pathways. For example, 14C is a radioactive isotope of carbon and naturally occurs at much lower rates than non- radioactive 12C (i.e. most molecules contain 12C carbon atoms). A cell can be fed a nutrient molecule labeled with the radioactive isotope and scientists can detect where the radioactive isotope ends up. For each of the following scenarios, trace the radioactive isotope to where it ultimately would end up after moving through the cellular respiration, fermentation, or biosynthetic pathways. Only consider these metabolic pathways; do not consider any other cellular processes.
A. E. coli is fed 14C- labeled glucose and grown under aerobic conditions.
B. E. coli is fed 14C- labeled glucose and grown under anaerobic conditions (fermentation).
C. E. coli is fed 14C- labeled fatty acids and grown under aerobic conditions.
D. E. coli is fed 14C- labeled acetyl CoA and grown under conditions that promote biosynthetic pathways.

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Definitions:

Equifinality

A principle that states in complex systems, a given end state can be reached by many potential means or from different initial conditions.

Multifinality

A principle in psychology that suggests the same beginnings can lead to multiple outcomes, highlighting how varied end states can arise from the same initial condition.

Social Media

Platforms and technologies that enable users to create, share content, and participate in social networking on the internet.

Systems Theory

A theoretical framework that analyses complex phenomena as systems of interrelated components, emphasizing whole-system behaviors rather than the properties of individual parts.