What is the effect of genetic drift in which a population size is reduced drastically for a short period of time, causing a long term reduction in genetic variation for that population

Agroup of organisms that changes over time is said to

Which of the following statements is true regarding a basic amino acid? a.) the hydrophilic r group of a basic amino acid will be located on the interior of a protein b.) the positively charged r group of a basic amino acid could bind dna c.) the r group of a basic amino acid would only be able to form covalent bonds with other molecules d.) a basic amino acid would be considered both polar and hydrophobic e.) all of the above

Satellites orbit earth in the a) mesosphere b) troposphere c) stratosphere d) thermosphere