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:
<u>the bottleneck effect</u>
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Explanation:
Genetic drift has an important impact on the small populations. mutations, which are spontaneous heritable changes in the genetic code, made up of DNA. Here, mutations accumulate over time in a group, modifying the distribution of alleles or various forms of a gene. Natural selection may result in a loss of diversity in a population called genetic drift; one trait's allelic frequency rises while others become less prevalent. Typically such differences exist because of occurrences of mutation and recombination.
Some mutations or alleles may become extinct from the population.
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Variants of a gene accumulate and are transmitted across generations; the frequencies of these occurrences are altered and become more stable in genetic drift- they become genetically distinct and may eventually form a new species after isolation. This may be further compounded through other phenomena such as the founder effect where a group separates and genetic diversity decreases; and the bottleneck effect where barriers to reproduction or the die-off a population increases genetic drift.
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Eukaryotes
Nuclear
Divide
Organelles
Membrane
Evolved
Molecules
Brane
Regulating
Active
Nucleus
Endoplasmic
Hope thats what you need!
B - energy flow from one tropic level to the next
