MIC 102 Midterm questions with correct answers

Microbe CORRECT ANSWER -Free living organisms so small that they are only visible under the microscope. -Viruses are not really microbes- they lack one key quality of living cells; the capacity to main their bodily integrity throughout their life cycle. -Exceptions: Epulopiscium fishelsoni is huge (600+ um), Mycobacterium leprae is not free living. -Bacteria, Archaea, Fungi, Protists. LUCA CORRECT ANSWER -Last Universal Common Ancestor= microbe -About 4 bya -Core features for cellular life on Earth: +DNA as genetic material +Protein and RNA +Lipid membrane ~used to be a bacterium Mapping evolution: phylogenetic trees CORRECT ANSWER -Base changes indicate divergence from common ancestor -Molecular clock: does not change fast + keep track of changes. +Selectively neutral changes +Conserved regins +Found in all organisms -Small subunit (16S) rRNA gene generally fits the bill - rRNA + protein, cares about structure the same way protein does + cannot change too much.