Killing pollen increases the fitness of the

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Killing pollen increases the fitness of the mitochondria and chloroplasts when resources not spent on pollen production are diverted to increase egg (seed) production. Recent studies indicate that mitochondria that kill pollen can be suppressed by plant genes located on the nuclear chromosomes that have that evolved to block the pollen-killing molecular pathway. 96) Coevolution between mitochondrial genes that kill pollen and the nuclear genes of the plant that suppress pollen-killing would be an example of: A) The interspecific Red Queen B) The intraspecific/intergenic Red Queen C) Interspecific mutualistic coevolution D) Intraspecific mutualistic/intergenic coevolution E) Answers A & B are both correct 97) If pollen were killed by intracellular bacteria that are only transmitted through the eggs, then coevolution between the bacteria (genes killing pollen) and the nuclear genes of the plant (that suppress pollen-killing) would be an example of: 98) If a gene in the genome of an intracellular bacteria (only transmitted via the egg) evolved to reduce pollen production and thereby increase egg (seed) production, then:
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99) Suppose that it was found that pollen-killing was accomplished by genes located on both the mitochondria and the chloroplast. The evolution of pollen-killing by genes located on both organelles would represent: 100) Pollen fertilizes eggs by producing (growing) a tube that penetrates the plant tissue surrounding the egg and fertilization takes place when the pollen tube reaches the egg and delivers the haploid pollen nucleus. Many pollen grains typically reach a single flower and produce pollen tubes, but it is only the fastest pollen tubes (usually a very small proportion) that reach the flower’s eggs first and fertilize the eggs. You can assume that polyspermy has the same effect in plants as it does in abalone. Given this information, you would expect what evolutionary interaction between a gene that regulates the rate of pollen tube growth (Gene P) and a gene that controls the chemical composition of the maternal tissue surrounding the flower’s eggs (gene E): A) Evolution by a pathogenic fungus that gains access to eggs by penetrating their surrounding tissue can cause intraspecific/intergenic mutualistic coevolution between genes P and E. B) Evolution by a pathogenic fungus that gains access to eggs by penetrating their surrounding tissue can cause interspecific mutualistic coevolution between genes P and E. C) Evolution by pollen to increase it competitive ability can cause intraspecific/intergenic antagonistic coevolution between genes P and E. D) Evolution by pollen to increase it competitive ability will drive interspecific antagonistic coevolution between genes P and E. E) Both answers A and C are correct
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