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1. Ribosomes are made in the . a. cell membrane d. smooth endoplasmic reticulum b. nucleolus e. rough endoplasmic reticulum c. nucleoid Ribosomes are produced in the nucleolus (a part of the eukaryotic nucleus) and are found loose in the cytoplasm or attached to the endoplasmic reticulum. In this condition the endoplasmic reticulum is called the rough endoplasmic reticulum or RER. 2. Which of the following statements does NOT describe mitochondrial DNA? a. Yours was inherited solely from your mother. b. It is replicated in the nucleus. c. It can be used to help trace the evolutionary descent of humans and other organisms. d. It does not cross over when cells undergo meiosis. e. none of the above Mitochondrial DNA is inherited with mitochondria in the egg which comes from your mother. The mitochondria and its DNA are replicated within the cytoplasm of all your cells and the genetic information (DNA) in the mitochondria is never directly involved with the chromosomal DNA of the nucleus. The relationships between organisms can sometimes be followed by the relative comparisons of mitochondrial DNA. 3. Avery, MacLeod and McCarthy achieved bacterial transformation by incubating bacteria with __________________. a. heat-killed bacteria d. DNA b. live bacteria of a different strain e. chromatin c. protein f. none of the above In the 1920’s the Griffith’s transformation experiments mixed heat-killed bacteria with live bacteria and traits from the dead, heat-killed bacteria were transferred to the live bacteria. The experiments of Avery et al. used these transformation experiments to demonstrate, for the first time, that DNA could be the transforming principle, therefore, DNA was the hereditary material. 4. In the Meselson-Stahl density labeling experiment the semi-conservative replication of DNA was shown by following transfer to N14 medium. a. the formation of all N14 labeled DNA after 1 fission b. the formation of hybrid N14-N15 DNA after 1 fission c. the formation of all N15 DNA after 1 fission d. the formation of all N14-N15 DNA after 2 fissions e. the formation of all N14 DNA after 2 fissions If all the DNA is N15 prior to the density transfer experiment, then all new DNA will be produced with N14 following the density transfer. Therefore, if DNA replication is semi-conservative, after one generation all DNA will be hybrid, that is one-half N14 and one half N15. After 2 generations, one-half will be hybrid and one-half will be all N15. 5. Mitochondria and plastids contain their own DNA which encodes all the proteins contained within the organelle. a. True b. False Mitochondria and plastids contain DNA that probably once contained the information to encode all the proteins contained within the organelle, however at this time, we have discovered that many of these proteins are now encoded in the nuclear genes of the eukaryotic cell. So the symbiotic relationship between the organelles and the host cell has become a dependent one for both the mitochondria and the eukaryotic cell. 6. A nucleosome is a “nuclear body” which contains histone proteins and is surrounded with approximately 150 nucleotide base pairs of DNA and separated from adjacent nucleosomes by an approximately 50 nucleotide base pair “linker.” a. True b. False Nucleosomes have become recognized as a standard organizing factor for most eukaryotic cells and our understanding of their basic structure will eventually lead us to an understanding of how the eukaryotic nucleus is organized so it can do its work so efficiently. 7. In 1800's what did philosophers, scientists and the public believe about plants and animals in regards to evolution? a. they evolved around the same time with new species developing all the time. b. there was an evolutionary period for each c. they had no set date or time d. created at one time and that new species had not been introduced since then. e. none of the above 8. Which evidence supported Darwin’s theory of organic evolution? a. the Galapagos Islands with regards to the giant tortoise and the finches (birds) b. the world being round c. the sea d. organic material found on the sea floor. e. none of the above 9. The electron micrograph below shows a eukaryotic cell containing prokaryotic, cyanobacterial, endosymbionts. a. True b. False 10. Chloroplast DNA is located in the . a. stroma of the chloroplast d. within the cell wall of the plant b. in the cytoplasm e. none of the above c. between the inner and outer membrane The stroma is the “cytoplasm” of the plastid or chloroplast; the matrix is the “cytoplasm of the mitochondrion. In both cases, the DNA is located within the organelle and the organelle is located in the cytoplasm of the eukaryotic cell. 11. Very briefly describe one (1) of the following: A. Describe the Howard and Pelc experiment that established the cell cycle. B. Describe the organization of the eukaryotic genome. C. What is bacterial transformation, and what was the significance of the Avery, McCloud, and McCarthy pneumococcus transformation experiment? D. What were the details of the Meselson-Stahl demonstration of the semi-conservative replication of DNA?