#Question id: 1364
#Unit 4. Cell Communication and Cell Signaling
In mice engineered to overexpress the syndecan-1 gene in the hypothalamic region of the brain and other tissues, normal control of feeding by antisatiety peptides is disrupted, and the animals overeat and become obese. Other studies have shown that syndecan-3 may also be involved in the regulation of feeding behavior. Given the following information, which of these outcomes might you expect in experimentally manipulated mice?
I. Hypothalmic expression of syndecan-3 is increased by fasting.
II. Syndecan-3 knockout mice are resistant to diet-induced obesity.
III. Heparinase can cleave syndecan-3 to release heparin sulfate GAG chains that may suppress the activity of antisatiety peptides and feeding behavior.
Following statements are:
A. Overexpression of heparinase in mice with normal levels of syndecan-3 would result in resistance to diet-induced obesity.
B. In mice with normal levels of syndecan-3, fasting followed by free access to a high-fat diet would lead to resistance to diet-induced obesity.
C. Lack of heparinase in mice with normal levels of syndecan-3 would result in animals that overeat and become obese.
D. Overexpression of heparinase in syndecan-3 knockout mice would reverse the resistance to diet-induced obesity.
Which of the following combination is correct?
#Question id: 32302
#Unit 1. Molecules and their Interaction Relevant to Biology
#Question id: 4712
#Unit 11. Evolution and Behavior
Which of these conditions are always true of populations evolving due to natural selection? Condition 1: The population must vary in traits that are heritable.
Condition 2: Some heritable traits must increase reproductive success.
Condition 3: Individuals pass on most traits that they acquire during their lifetime.
#Question id: 15721
#Unit 11. Evolution and Behavior
#Question id: 14781
#Unit 13. Methods in Biology