where they execute important functions. The polypeptide chain of these proteins must cross the lipid bilayer. This presents a problem because the peptide bond is polar in nature. It turns out that in virtually all cases where an amino acid chain crosses a lipid bilayer it does so as an alpha helix. Suggest a reason why this is the case. (5 points)

ans.

in united states (us), the first leading cause of death for both women and men is heart diseases that leads to more than half of the deaths. heart diseases develop due to narrow arteries, buildup of plaque in blood capillaries that arises difficulties in blood flow.

the second leading cause of deaths in us is cancer that affects individuals of all ages. it develops due to uncontrolled growth and spread of tumor cells, which results in death if the not controlled or treated.

the third leading cause of deaths in us is copd or chronic obstructive pulmonary disease. it includes difficulty in breathing, chest infections, and persistent cough. smocking is a leading cause of copd and around 80% of copd deaths occur due to smoking.

thus, the correct answer is 'option). cancer, copd, and heart disease.'