12. The following is incorrect regarding mitochondria and plastids: A) They originated by invagination rial DNA is homologous to that of ricketsias C) Chloroplasts originated from D) They have bacterial-type 70S ribosomes E) None of the above. 13. One of these techniques is mismatched with the specimen under study. Which one is i? on bacterial cell wall surfaces-Atomi force microscopy B) Stained bacterial cells-Bright-field microscopy l Detection of moving bacterial flagella-Scanning electron microscopy D) Intracellular compartments in live eukaryotic cells-Phase contrast microscopy e) Polysomes (ribosomes on single mRNA molecules-Transmission electron microscopy 14. Which of the following is not true of transmission electron microscopy (TEM)? A) The specimen is usually foxed and embedded. B) It produces three-dimensional images of an uncut object’s surface C) The embedded specimen is cut into thin sections with a microtome. is The requirement for a vacuum prevents the viewing of live organisms. E) ) Electrons are focused using a magnetic field running along the beam. In fluorescence microscopy, incident light is absorbed by the specimen and reemitted at a aenergy, resulting in A) lower, shorter B) higher, shorter C) lower, longer D) higher, longer E) None of the above 16. What unit of length would you generally use to measure a virus? C) mm A) cm B) nm E) m 17. Cell length is usually measured in- A) nanometers, nm, 10-9 m B) C) microliters, mL. 10-6L D) milliliters, mL, 10-3L E) micrometers,urn, 10-6 m milimoles, mM, 104 M 18. The Mimivirus (illustrated on the figure on the right) infests the amoeba Acanthomoeba polyphaga. The following is correct regarding the mimivirus. A) It possesses metabolic genes (for nucleotide synthesis, among others) B) The prefix “mimi” indicates that it mimics bacteria (at least in size!). C) It is being studied for possible association with the disease Legionellosis. D) It has its own “satellite” virus (Sputnik). E) All of the above. 19. pH and is an indicator ofthe the pH, the higher the concentration of protons in a soluti A) [A-JAM, density: higher B) -log [H-J, acidity; lower C) -log [OH-], alkalinity: lower D) pKa, alkalinity, higher E) None of the above 20. What is the proportion of H3N-CH2-Coo4.HsN-CH2-COOH at pKa? 100%10 75%)25 A D25%/7 0%)10.0% 21. What is the proportion of H2N-CH2-COO-/-HsN-CH-COO-at pH 10.26? A 100% B 75%)2S0 C 50%)5 0’/o 25%/75%, D E 0%/10 ne