Answer:
D
Explanation:
The only way for giraffes to evolve over time towards having long necks would be to have genetic differences that were gradually favored over time. As in, the giraffes that were genetically disposed to have necks just a bit longer eventually survived longer, because they could eat high leaves, while those with short necks died, and the long-necked giraffes reproduced more, which increased the allele frequencies of long necks in the species over time.
Never, never say A or B!! This is known as Lamarck's theory of inheritance of acquired characteristics, and it's simply wrong.
C is wrong, because the mutation must occur in the original zygote.
There are different classes of mutation but the descriptions given here are specifically applied to cystic fibrosis, particularly referring to the CFTR (<span>Cystic fibrosis transmembrane conductance regulator) </span>gene.
<u>Mutation Classes</u>
Class I - Gene contains a stop signal that prevents CFTR from being made.
Class II - CFTR is made, but does not reach the cell membrane
Class III - CFTR is made and in the right place, but does not function normally
Class IV - Channel does not move substances efficiently or at all
Class V - <span>CFTR is made in smaller than normal quantities
(Source: </span>https://www.biologycorner.com/worksheets/case_study_cystic_fibrosis.html)
Given these different classes, the easiest one to correct would most likely be Class V, since in this type of mutation, the only problem or abnormality is the production of insufficient amounts of the needed CFTR.
The cause of the mass drop of population of Hispaniola before 1542 was due to the Smallpox outbreak. The first outbreak of smallpox, occurred during December 1518 or January 1519. The Smallpox Outbreak, claimed the lives of almost 90% of the Native Americans. By 1548, the population of Taino had declined and lessen to fewer than 500 people.
Answer:
Option D, The chance that you share an allele with either a parent or a sibling is one half.
Explanation:
All individuals receive 50 percent of their genes from each parent, Thus, it can be said that each sibling will share nearly half of their genetic material with each parent. In case of full siblings (when both the parents are same), 50 percent of their genetic material matches.
For instance,
There are two parents each with genotype AA and aa
Cross between AA and aa will produce following offspring
AA * aa
Aa, Aa, Aa, Aa
Thus, each offspring will have one gene from each parent and hence they share 50% of their genetic material with their parents
Two siblings get the same gene from their two parents. Hence, 50 percent of their genetic material matches.
Hence, option D is correct