BIO 221 Final Exam Study Questions and Correct Answers

The three main branches in the phylogenetic "tree" of life are _____ bacteria, archaea, and eukaryotes Tyndall repeated his experiments, but he obtained different results. This was because ___ the media he was trying to sterilize contained endospores Viroids are ___ small pieces of RNA without a protein coat Why is it important that most intermolecular interactions in cells are weak bonds? they are more easily reversible The pH inside a bacterial cell is 7. The pH outside the cell is 6. What is the size of the H+ gradient? there are 10 times as many protons outside than inside the cell These viruses infect the bacterium Escherichia coli. Which of the following statements MIST also be true? they cannot infect humans What makes a biological strong bond strong? electron sharing between atoms in the bond Nucleic acids are put together from their monomers, nucleotides, with ___ bonds. phosphodiester Two molecules are composed of the same atoms, but the molecules have different molecular weights. This can be explained by the existence of ___. isotopes Which of the following is true about a condensation reaction to produce a macromolecule from its monomers? it generally requires energy input Which of the following lipids would be the most fluid at room temperature lipids with 3 cis-unsaturated fatty acids What type of microscope measures electric current passing through a probe rather than using part of the electromagnetic spectrum? atomic force How does an amino acid get through the outer membrane of Gram-negative bacteria? through special facilitated diffusion protein channels