A 1600-lb elevator is suspended by a 200-ft cable that weighs 10 lbyft. How much work is required to raise the elevator from the basement to the third floor, a distance of 30 ft?
Study Guide for Midterm #2 Bio 151 RNA World Hypothesis -RNA system that replicates in two steps 1. Self replicating RNA 2. RNA acted as a template for forming 3. Proteins then aid in replication of RNA 4. Make DNA from RNA for storage of info -Problems: Clutter with other molecules, efficiency of ribozyme Prokaryotes most likely came before Eukaryotes -Prokaryotes infolding of membrane to make nucleus Endosymbiont: theory for semiautonomous organelles -organisms living together in direct and intimate contact -mitochondria and chloroplasts both contain small amounts of circular DNA Nucleus: contains chromatin and nucleolus -chromatin: strands of chromosomes -nucleolus: sit of rRNA synthesis, assembly of large and small