<span>Point mutations are of two types: Substitutions of bases that are the change of one base of DNA by another. And Transitions that are replaced on a pyrrhic basis by another pyrrhic or a pyrimidine by another pyrimidine. Transversions: substitution of a pyrrhic base by another pyrimidine or vice versa. These mutations are negative because they affect only one of the nucleotides, and therefore, only one triplet of bases are affected. When the mutation does not affect the individual it is a silent mutation. Chromosomal mutations Changes in the structure of the diploid chromosomes, where one of the chromosomes has a mutation, will have another normal. They can hinder the process of meiosis in the carrier since it hinders the correct pairing of the homologous chromosomes. It would produce an unfeasible offspring or with mutations.</span>
Answer:
b) At equilibrium, the species composition of an island will not change.
Explanation:
The Theory of Island Biogeography written by Robert H. MacArthur and Edward O. Wilson (1967) is an essential book for any professional working in biogeography, biodiversity, ecology, conservation and related fields. The theory of island biogeography states that species diversity on islands tends to approach a dynamic equilibrium due to the balance between colonization (inmigration), speciation and extinction. At equilibrium, the species composition of an island will change, precisely at the time that immigration and extinction processes maintain the number of species in a dynamic equilibrium, thereby maintaining species diversity. In this case, the colonization rate represents a function of distance to the continent (or other islands), the extinction rate is a function of the size of the island and habitat heterogeneity, and speciation is a function of time. This book also contains a series of useful considerations: 1-the number of species in an area is directly associated with the size of the area; 2-large islands support more diverse communities than small islands; 3-the viability of populations on island systems can be considered as a function of the island size and its proximity to the mainland (or other islands); and 4- when a habitat is lost the remaining fragmented area may lose some of its important species.
The blood cells likely placed in a "hypotonic solution".
<u>Option: A</u>
<u>Explanation:</u>
When human blood cells are immersed in a solution with a low concentration of solute than is present in cells, osmosis allows water to pass through the cells, allowing the cells to get swollen; such a fluid is hypotonic to the cells. But when held in a solution with a greater concentration of solute, osmosis allows water to pass out of the cell, the cell is smaller and crenated in form; then a solution is hypertonic to the cells.
Healthcare facilities preserve human blood cells in a plasma solution that has the proper salt and protein ratios. Such solution is formulated to be mildly hypertonic to the red cells, thus maintaining the integrity of the cells and avoiding hemolysis.