When an antigen attacks the body, it activates adaptive immunity. This adaptive immunity produces a strong response when it encounters the same antigen for the second time. Which feature of adaptive immunity is essential for this kind of response? A. the ability to remember the antigen it encounters B. the ability to distinguish between self and nonself antigens C. the ability to produce nonspecific antibodies against the foreign antigen D. the ability to secrete lysozymes against pathogenic antigens

The dna in a cell’s nucleus encodes proteins that are eventually targeted to every membrane and compartment in the cell, as well as proteins that are targeted for secretion from the cell. for example, consider these two proteins: phosphofructokinase (pfk) is an enzyme that functions in the cytoplasm during glycolysis. insulin, a protein that regulates blood sugar levels, is secreted from specialized pancreatic cells. assume that you can track the cellular locations of these two proteins from the time that translation is complete until the proteins reach their final destinations.for each protein, identify its targeting pathway: the sequence of cellular locations in which the protein is found from when translation is complete until it reaches its final (functional) destination. (note that if an organelle is listed in a pathway, the location implied is inside the organelle, not in the membrane that surrounds the organelle.)

Asegment id dna that is artificially created from two or more organism through use of dna enzymes in a laboratory is called a segment of dna that is artificially created from two or more organisms through use of dna enzymes in a laboratory is called

Even though the ostrich is a flightless bird, ostriches still possess wings that stretch approximately two meters across when fully extended. scientists speculate that when dinosaurs became extinct, some of the birds that lived during that time became land dwellers since they were able to consume the food that the dinosaurs once ate. over time, these species grew larger and heavier. eventually, the ostrich species became too big to fly. the wings found on ostriches are known as a. analogous structures. b. homologous structures. c. vestigial structures. d. symmetrical structures.