a structure in the chloroplast of photosynthesizing cells, usu. one of an interconnected stack, having a pigmented membrane that is the site of photosynthesis. [< German Thylakoid (1961) < Greek thÈ³lakoeidá¸s resembling a bag =thylak(os) sack + -oÄidÄs -oid]
Round or rump roast almost two hours to reach medium rare, 3-pound roast six hours on low or longer. In a crock pot. On the stove top in a Dutch oven around two hours. Extra 15 minutes may be extended for medium or 30 minutes for well done. (source: http://www.ehow.com/way_5260879_long-cook-pound-roast.html).
Step 3. Cook the roast at 300 degrees F for 15 to 30 minutes per pound, depending on whether you want rare, medium or well-done beef. Cook for 3 to 4 hours total for a well-done roast; the meat should fall apart when done. Use an instant-read thermometer to check for doneness.