People who are infected with HIV do not get sick immediately. It can take the body months to attempt to fight off the virus and for a patient to test HIV-positive. So, paradoxically, the period when an HIV-positive person is most infectious coincides with the period he or she is least likely to know their status.
The ATP synthase of mitochondria and chloroplasts is an anabolic enzyme that harnesses the energy of a transmembrane proton gradient as an energy source for adding an inorganic phosphate group to a molecule of adenosine diphosphate (ADP) to form a molecule of adenosine triphosphate (ATP).
â¢ Some ATP is also generated in glycolysis and the Krebs cycle by substrate-level phosphorylation. â¢ Here an enzyme transfers a phosphate group from an organic molecule (the substrate) to ADP, forming ATP. Copyright Â© 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. 9.7.