Answer: Base pairs are formed when adenine forms a hydrogen bond with thymine, or cytosine forms a hydrogen bond with guanine. The second part of a nucleotide is the phosphate, which differentiates the nucleotide molecule from a nucleoside molecule.
Explanation:
Breathing in air pollutants can irritate your airways. It may cause shortness of breath, coughing, wheezing, asthma episodes and chest pain. Overtime, exposure to air pollution puts you at risk for lung cancer, heart attack/strokes, etc. Some people are more at risks from others though
Answer:
D) a scientific journal about chemistry and a biography of a famous chemist
Answer:
c. Pyridostigmine binds to the acetylcholinesterase active site and prevents sarin from binding to and modifying the enzyme active site.
Explanation:
Sarin is a toxic compound which inhibits acetylcholinesterase enzyme. This enzyme degrades the neurotransmitter acetylcholine after the required muscle cell stimulation. In absence of its activity, acetylcholine is not degraded and the muscle cells are stimulated uncontrollably. The muscles are not able to relax which ultimately proves fatal for the victim.
Pyridostigmine is also an acetylcholinesterase inhibitor like Sarin. However its period of inhibition is short compared to organophosphorus inhibitors like sarin. It competes with sarin and replaces it in the active site of acetylcholinesterase. The enzyme is still inhibited but for a shorter time as compared to inhibition by Sarin. Hence after sometime, it becomes functional again and resumes its normal activity. Acetycholine starts getting degraded relaxing the muscles.