Answer:D
Explanation: The pulmonary air sacs of birds only permit a unidirectional flow of air through the lungs. Unidirectional flow means that air is inhale and exhale through one trachea alternatively. This means the bird lungs only receive largely fresh air which has a high oxygen content during inhalation and do not receive fresh during exhalation. While air flow bidirectional in mammals.
I believe that all the above are ethical concerns regarding genetic engineering. Ethics is the study of moral or socially acceptable behavior. With the advent of genetic engineering and the ability to modify the genome of various organs, many ethical questions arise concerning the various scenarios and possibilities. There are many ethical concerns regarding genetic engineering in plants, animals, and humans. One of the ethical concerns regarding genetically modified plants used for food is whether the nutritional value will be sacrificed in favor of a higher yield or drought resistantancy.
Answer:
The duplication of a cluster of four Hox genes is equally likely as the duplication of a single Hox gene.
Explanation:
This comes from the definition of the parsimony principle, which is the action of choosing the simplest scientific explanation fitting the given evidence, meaning that all other elements are equal when evaluating the hypothesis. In biology the best hypothesis is the one that requires the fewest evolutionary changes.
Since three independent duplications of an individual Hox gene is in evolutionary terms, more complex than a single duplication or a cluster, then that hypothesis would be the most parsimonious.
