Which of the following members of Domain Archaea might be found in the stomachs of ruminant herbivores, such as cows and sheep?
a) thermoacidophiles
b) cyanobacteria
c) halophiles
d) methanogens
e) dinoflagellates
Answer: d) methanogens
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True or false: Amino acids can be spontaneously generated in vitro, but only under anaerobic conditions
A. true B. false
What is the sequence of events involved in the production of proteins that is secreted?
A) A hormone signals the gene that encodes the protein to be transcribed into mRNA in the nucleus. The mRNA is translated into protein on the ER, then processed and folded in the Golgi apparatus, and then sent out of the cell in a vesicle. B) A hormone signals a protein-filled vesicle to move from the plasma membrane into the cell and into the nucleus, where it stimulates transcription of the appropriate gene into mRNA. The mRNA exits the nucleus and is translated into protein on the ER and processed and folded in the Golgi apparatus. Finally, the protein is transported out of the cell in a vesicle. C) A hormone binds to the plasma membrane, signaling proteins near the membrane to fall apart into amino acids. These enter the nucleus and stimulate replication of the gene encoding the protein. D) The protein is produced as a linear molecule in the nucleus, then exits through nuclear pores. On the ER the protein folds into its active form and at the Golgi apparatus is packed into a vesicle, which carries it across the plasma membrane and out of the cell.
Which one of the following is a problem associated with traditional vaccines as opposed to vaccines produced by transgenic organisms?
A) Traditional vaccines are always in short supply. B) Traditional vaccines may result in disease symptoms because they contain killed or weakened organisms. C) Traditional vaccines can only be given after infection; they cannot prevent infection. D) Traditional vaccines must be given in larger quantity. E) Traditional vaccines are more expensive.
Which radical idea did Cuvier propose based on his studies of Earth’s history??
a. extinction of species
b. evolution of species
c. Earth as billions of years old
d. an unchanging Earth
e. static species composition