6 public questions tagged with this topic.
Neutrons = 12. ²³₁₁Na also has 12 neutrons.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Discovery of Subatomic Particles - Electron Proton Neutron
Radioisotopic labeling commonly uses phosphorus-32 because of its superior nuclear characteristics for nucleic acid detection. 32P is a high-energy beta emitter with a half-life of approximately 14.3 days, offering excellent sensitivity and short autoradiographic exposure times. It can be incorporated internally using [alpha-32P]dATP or dCTP during polymerization, or terminally as [gamma-32P]ATP via kinase reaction. Lower-energy isotopes like tritium, sulfur-35, and carbon-14 emit weak beta particles, require prolonged exposure, and provide poorer resolution. Hence 32P remains the isotope of choice for high-sensitivity probe labeling.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.
Phosphorus is central to nucleic acids, ATP, and phospholipids, so tracking its movement requires an isotope of the same element. Phosphorus-32 is a radioactive phosphor that chemically behaves identically to stable phosphorus but emits high-energy beta particles detectable by counters and autoradiography. Incorporated into phosphate pools, it labels DNA, RNA, and phosphorylated intermediates, allowing measurement of uptake, transport, and turnover. Carbon-14 labels carbon skeletons and iodine isotopes label proteins, making phosphorus-32 uniquely suited for specifically following phosphate metabolism in cells and ecosystems.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.
A neutron converts into a proton correctly describes the effect or change asked about in this question. In Atoms and Molecules, understanding cause-and-effect relationships is essential for predicting biological outcomes. A neutron converts into a proton occurs because of specific molecular interactions, thermodynamic principles, or regulatory mechanisms that govern this biological process. The other options (A proton converts into a neutron, An electron is captured, and Energy is released without a change in mass) describe either opposite effects, effects that occur under different conditions, or changes associated with unrelated processes.
Ref: Campbell Biology, Urry et al., 12th Ed.
They always have the same chemical properties. is the correct choice because it does not accurately describe or belong to the category addressed in this question. In the context of Atoms and Molecules, the other options (They have the same atomic number., They have the same number of protons., and They have different atomic masses.) are all valid and well-established concepts. They always have the same chemical properties. is either unrelated to the topic, describes a different biological process, or represents a common misconception. Questions framed as 'which is NOT' require students to identify the exception among otherwise correct statements, demanding comprehensive knowledge of the topic rather than recognition of a single fact.
Ref: Campbell Biology, Urry et al., 12th Ed.
The neutron-to-proton ratio is the scientifically accurate answer to this question. Within the study of Atoms and Molecules, this concept is well-established through extensive research and is documented in standard scientific literature. The specific properties, mechanisms, or characteristics of The neutron-to-proton ratio directly address what is being asked. Among the other options, The number of protons, The number of electrons, and The number of valence electrons do not correctly answer this question because they either refer to different concepts, describe properties of other molecules or processes, or represent common misconceptions about this topic.
Ref: Campbell Biology, Urry et al., 12th Ed.
