A) A textbook definition would be that genetic drift is: a random change in allele frequency caused by a series of chance occurences that cause an allele to become more or less common in a population. In layman's terms, this means that genetic drift happens when luck makes the genetic pool of the population to deviate from what is expected.
B) The cause for this genetic drift is the aformentioned couple. Because amish communities are small and they select partners from their community, having even a couple of carriers of alleles in a community can make the allele freuency much larger than expected; for example, if the community was 100 persons, the percentage would be in the order of 1%, still much larger than the general population. Thus, the cause here is that a small population had a couple of carriers.
C) Sexual reproduction leads to a mixing of alleles from both mother and father and helps diversity. When a population is isolated, the gene pool is fixed and no new genes can come in, reducing diversity. Also some people that have an allele might die, hitting diversity even more. Finally, having a small population creates a strong pressure in some circumstances that leads to elimination of some traits and diversity.
The common characteristic of those two organisms is hard spherical shells (exoskeleton).
Foraminiferans are single cell marine eukaryotes divided into granular endoplasm and transparent ectoplasm. Foraminiferans are enveloped with tests, hard shells, usually composed of calcium carbonate (sometimes from organic compounds or silica).
Coccolithophore is a unicellular, eukaryotic alga with special calcium carbonate plates (or scales) of uncertain function (coccoliths). Each unicellular alga is enclosed in its own collection of coccoliths, the which make up its exoskeleton- coccosphere.
Answer:
I feel happy and sorry.
Explanation:
I have different feelings when I go back and analyze the decisions and actions I have taken in the past few days because some of my decisions are right and some are wrong. I feel happy when I go back and find out my decision and actions were right, while on the other hand, I feel sorry when I find out that some of my decisions and actions were wrong.
