Answer:
Plants and animals assimilate carbon-14 from carbon dioxide throughout their life. When they die, they stop exchanging carbon with the biosphere and their carbon-14 content begins to decrease at a rate determined by the law of radioactive decay.
Radiocarbon dating is basically a method designed to measure residual radioactivity.
Explanation:
Carbon-14 is a weakly radioactive carbon isotope; It is also known as radiocarbon, and is an isotopic stopwatch.
Radiocarbon dating is only applicable to organic materials and some inorganic materials (not applicable to metals).
Proportional gas counting, liquid scintillation counting, and accelerator mass spectrometry are the three main methods of radiocarbon dating.
The radiocarbon, or carbon-14, is an isotope of the carbon element that is unstable and weakly radioactive. The stable isotopes are carbon-12 and carbon-13.
Carbon 14 is continuously formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen-14 atoms, rapidly oxidizing in the air to form carbon dioxide and entering the global carbon cycle.
Accelerator mass spectrometry (AMS) is a modern method of radiocarbon dating that is considered the most efficient way to measure the radiocarbon content of a sample. In this method, the content of carbon-14 is measured directly in relation to carbon-12 and carbon-13 present. The method does not take into account beta particles, but the number of carbon atoms present in the sample and the proportion of the isotopes.
1. Break down of Food into Energy 
Oxygen
2. Absorb X - Rays in Bones Calcium
3. Cell Membrane Function Sodium
4. All Organic Compounds Carbon
Answer:
D.
Explanation:
Solar energy is needed for photosynthesis, and chemical energy in the form of glucose is needed for cellular respiration.
Answer: The correct answer to the fill in the blank is Mitosis.
Mitosis is a type of cell division that results in the formation of two daughter cells having the same number of chromosomes as compared to their parent cell. Thus, by producing more number of identical cells, mitosis helps in the growth and repair of tissues.
Thus, after removal of cyst from the liver of Bob, the cells would grow and repair the area through mitosis.
<span>Endorphin. Endorphin are pepetide hormones secreted by the central nervous system and the pituitary gland. They inhibit the transmission of pain signals; they also produce a feeling of euphoria very similar to the ones produced by other opioids. Its 1 production is usually triggered by various human activities although they are produced in response to pain. Carrying out frequent exercise usually stimulates the release of beta-endorphin in the human brain known as runner's high. This is the probably the reason Mobombi could finish the race pain free.</span>
