The term that best completes the statement above is THYMUS. It is in the Thymus that T cells achieve self-tolerance. Typically, it is the thymus that produces all the T cells in the body and it is located in the <span>upper anterior part of your </span><span>chest. These T cells develop this so called central tolerance once it is in the thymus since this is where they are produced and mature. </span>
A dissolved oxygen level that is too high or too low can harm aquatic life and affect water quality. ... Fish and crustaceans obtain oxygen for respiration through their gills, while plant life and phytoplankton require dissolved oxygen for respiration when there is no light for photosynthesis
Answer:
A) dinosaurs, reptiles, and birds had a common ancestor
Explanation:
The dinosaurs have not evolved as a separate phylum that has not close relations with other animals, but instead they share a common ancestor with the likes of the reptiles and the birds. The reptilians have actually emerged before the dinosaurs, but the dinosaurs managed to take up the top niches in the food chain after they appeared never the less. The birds on the other hand are actually an evolutionary product of the diversification of the dinosaurs. the birds have actually evolved from small bipedal dinosaurs, that over time started to take up new way of life and appearance in order to conquer the skies.
Answer:
carbon 14 decays into nitrogen 14
once a living thing dies, it no longer takes in carbon
carbon 14 dating works for fossils as old as 50,000years