Q. Bryophytes and fern allies were most prevalent during early plant evolution; however, many of these plants have been replaced by vascular plants. These “lower” plants possess flagellated sperm that have to swim through an aqueous medium to reach and fertilize eggs. From this information, in what kinds of habitat […]

You have determined the DNA- binding site of a protein by determining the DNA footprinting after labeling one strand. To check your results, you repeat the experiment after labeling the other strand of the duplex. You find that the footprints are slightly offset from one another relative to the sequence […]

A plasma membrane with surface area of 5000 µm2; there are 106 phospholipid molecules per µm2 in each leaflet of the membrane; there are 3000 molecules of flippase enzyme associated with the plasma membrane; each flippase enzyme molecule can catalyze 100 flips per second (we’ll ignore enzyme specificity for the […]

Part 1 1. Nitrogen fixation is a natural process by which inert or unreactive forms of nitrogen are transformed into usable nitrogen. Why is this process important to life? 2. Given what you have learned about the hydrogen bonding shared between nucleic acids in DNA, which pair is more stable […]