To test for the presence of starch, iodine can be used. A positive reaction results in a black color. A dialysis bag filled with starch solution and secured on both ends is placed in iodine solution. After 30 minutes the dialysis bag appears black. Based on this information, what most accurately describes what happened?
A. Due to its size and polarity, starch was able to exit the dialysis bag and interact with the iodine solution.
B. Due to its size and polarity, iodine was able to enter the dialysis bag and interact with starch.
C. Over time, both iodine and starch are equally distributed throughout the two solutions.
B
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Which of the following procedures would identify the enzyme that catalyzes the carboxylation of ribulose-1,5-bisphosphate?
A) irradiating a leaf extract with red light B) introducing radiolabeled carbon dioxide into a plant extract and determining which molecules become radiolabeled C) purifying a variety of proteins from plant extracts and testing each protein individually to see if it can carboxylate ribulose-1,5-bisphosphate D) differential sedimentation of a protein extract
A colleague gives you two membrane fractions from a plant cell lysate. One contains the plasma membrane fraction, the other the mitochondrial fraction. The tubes are not labeled, but you run the samples anyway, looking at the macromolecule composition of the samples. You know for certain that the second sample contains the mitochondrial fraction simply because it contains insignificant amounts of
A) lipids. B) protein. C) specifically phospholipids. D) carbohydrates. E) both choices C and D
Which of the following is an example of a population?
1.all of the Bent-nosed clams in a mudflat in Elkhorn Slough, California 2.all of the invertebrates living in a mudflat in Elkhorn Slough, California 3.all of the organisms in a mudflat in Elkhorn Slough, California interacting with the physical and chemical environment 4.all regions of the Earth’s crust, waters, and atmosphere in which organisms live
Homologous recombination ________
A) occurs during meiosis as a normal process B) is used in plant cell activation C) must be used to produce animal bioreactors D) occurs when creating a knockout animal E) is a technique not proven to be successful