Nitric oxide was discovered as a secondary messenger in the 1980s and has grown in popularity since that time. In fact, it was n
amed molecule of the year in 1992 by Science Magazine, one of the leading global scientific publications, and the Nobel Prize in Physiology and Medicine for 1998 was awarded to the scientists who discovered its properties as a signaling molecule. Add to that the link to Viagra, one of the most profitable sexual enhancement drugs on the market, and you have a molecular superstar.
The main function of viagra is to relax the muscles of the blood vessels in some areas of the body. It is used for the treatment of erectile dysfunction and for high blood pressure. The component of viagra is a competitor to the enzyme PDE5, breaking down cGMP. In the penis, blood is trapped, which results in the erection being maintained. When cGMP levels decrease, the concentration of calcium ions increases, causing smooth muscle contraction.
Answer: B) The mother's father must also carry the recessive allele
Explanation:
How Are Men Affected by Cystic Fibrosis? Males account for slightly more than 50 percent of all cases of cystic fibrosis (CF) but generally have better outcomes than females until about age 20.
