Facilitated diffusion is usually significant to pass the ions across the hydrophobic layer of the plasma membrane. Transmembrane integral protein and careers proteins provide the channels that allow the ion to pass across the membrane. When an ion bind to their active site on the protein (note that the proteins are very selective), the protein changes conformation. It is this change in conformation opens up the channel that allows the ions to be passed across the membrane. When the ions are released inside of the cell, the protein resumes normal shape (and the channel also closes) and the active site becomes available again or another ion.
Answer:
This process would be the one truly responsible for the "evolution" of mitochondria and chloroplasts as we know them from their prokaryotic ancestors. The cell process that would have initiated endosymbiosis is endocytosis; the process of taking things inside the cell
I believe that hair and limbs are homology because all mammals have hair and similar limb structure. Hair loss and social behavior on the other hand are homolasy because not all mammals have them. Homology is the similar traits due to common ancestry while homoplasy is similar traits for other reasons other than common ancestry.
B. It is False
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