The important feature of a phospholipid that makes it well suited for a cell membrane is its amphipathic nature.  That means that one part of the molecule (the phosphate part) is very polar, so it mixes well with water, and the other part (the lipid tail of the molecule) is hydrophobic because it is non-polar.  So these molecules naturally form bilayers … Read more

Sometimes.  Maybe even more often than not.  However, after a few years, if you don't use what you learned, you can easily forget most of it.  I couldn't tell phloem from xylem anymore, since I haven't once needed to recall that information in the last 20 years.  (Well, not that I remember anyway. :-P)   Also, the way … Read more

Almost all eukaryotes have mitochondria, including the euglena.  Even things with chloroplasts use them.  That is because chloroplasts serve to capture the energy from sunlight and use it to make carbohydrates.  Just like cells without chloroplasts, though, a euglena can't use sugar directly to fuel its biological processes; it needs ATP.  In order to convert the chemical … Read more

I don't think I could bring myself to do something that ridiculous, no.