<span> Enzymes are usually proteins but some also contain nucleic acids (RNA in particular) and the list of chemical reactions that are catalyzed by RNA has been expanding. So the answer is proteins.</span>
<span>Radiochemical dating is the answer!</span>
The global average atmospheric carbon dioxide in 2019 was 409.8 parts per million (ppm for short), with a range of uncertainty of plus or minus 0.1 ppm. Carbon dioxide levels today are higher than at any point in at least the past 800,000 years.The carbon cycle describes the process in which carbon atoms continually travel from the atmosphere to the Earth and then back into the atmosphere. Since our planet and its atmosphere form a closed environment, the amount of carbon in this system does not change.
Answer:
b. They express the appropriate receptor.
Explanation:
The signal transductions are extraordinarily specific and sensitive. Specificity is achieved by a <u>precise molecular complementarity between the signal molecules and the recepto</u>r. For example, the thyrotropin-releasing hormone produces a response in cells of the adenohypophysis, but not in hepatocytes, which lack the receptors to this hormone.
The answer to you question in true.