The first signs of Huntington’s disease often appear when a person is in his or her 30s and 40s, but it can appear later in life. The earliest symptoms are often subtle, such as mood changes. Do you think the subtle presence of symptoms plays a role in this harmful gene persisting in our population? Why or why not?

evidence and logical support is essential for a scientist to do in order to maintain credibility. this is because no one can believe without any logic and without any evidence.hence a scientist can maintain credibility by proving himself and by answering logically so experiments prove very beneficial. logical hypothesis give conclusion which is acceptable. therefore, there are two main factors to maintain credibility by a scientist is evidence and logical support.

d. planting trees

the trees take in carbon to make oxygen.

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.