Coleman hypothesized that the product of the ob+ gene was the appetite-suppressing hormone. Therefore, the homozygous ob/ob mutant would be unable to synthesize that hormone, and its circulating level would be zero. Coleman also hypothesized that the product of the db+ gene was the the receptor for the appetite-suppressing hormone. Therefore, the homozygous db?db mutant would be able to respond to it. It would eat excessively and produce large amounts of body fat, which in turn would produce large amounts of appetite-suppressing hormone. In the absence of a receptor, the db/db mutant's hormone level would remain abnormally high.
Both the ob/ob mutant and the db/db mutant are obese because neither is capable of suppressing its appetite. The ob/ob mutant produces no appetite suppressing hormone and so eats excessively. The db/db mutant cannot respond to the appetite-suppressing hormone and therefore eats excessively.
Answer:
Middle adulthood, or middle age, is the time of life between ages 40 and 65. During this time, people experience many physical changes that signal that the person is aging, including gray hair and hair loss, wrinkles and age spots, vision and hearing loss, and weight gain, commonly called the middle age spread
Explanation:
1) closed circulation
2) The spleen can easily be damaged if someone suffers a sever injury to the stomach. When the spleen is damaged, it can cause pain in the abdomen, dizziness, and pain in the left shoulder.
The right ventricle pumps the oxygen-poor blood to the lungs through the pulmonary valve. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle through the mitral valve. The left ventricle pumps the oxygen-rich blood through the aortic valve out to the rest of the body.
1. Topographic map: I want to take a nature hike through the woods. I wonder if it is hillly?
2. Geologic Map: I want to study the physical features of my area, but also know what kinds of rocks it has.
Those should be the answers.
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