[Q]: Norm and Ian were two brothers. Norm was a totally normal individual, while Ian had Down syndrome. Their parents loved them both equally. Which brother didn't have a degree of mental retardation? Hint: One of the most common chromosome abnormalities is Down syndrome , due to nondisjunction of chromosome 21 resulting in an extra complete chromosome 21, or part of chromosome 21 ( Figure below ). Down syndrome is the only autosomal trisomy where an affected individual may survive to adulthood. Individuals with Down syndrome often have some degree of mental retardation, some impairment of physical growth, and a specific facial appearance. With proper assistance, individuals with Down syndrome can become successful, contributing members of society. The incidence of Down syndrome increases with maternal age. The risk of having a child with Down syndrome is significantly higher among women age 35 and older.
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[A]: Norm

[Q]: Two botanists studied different types of plants. Barb studied anemophilous plants, while her friend Faye learned about entomophilous plants. Which botanist learned less about large and feathery stigmas? Hint: Anemophilous pollen grains are light and non-sticky, so that they can be transported by air currents. They are typically 2060 micrometres (0.00080.0024 in) in diameter, although the pollen grains of Pinus species can be much larger and much less dense. Anemophilous plants possess well-exposed stamens so that the pollens are exposed to wind currents and also have large and feathery stigma to easily trap airborne pollen grains. Pollen from anemophilous plants tends to be smaller and lighter than pollen from entomophilous ones, with very low nutritional value to insects. However, insects sometimes gather pollen from staminate anemophilous flowers at times when higher-protein pollens from entomophilous flowers are scarce. Anemophilous pollens may also be inadvertently captured by bees' electrostatic field. This may explain why, though bees are not observed to visit ragweed flowers, its pollen is often found in honey made during the ragweed floral bloom. Other flowers that are generally anemophilous are observed to be actively worked by bees, with solitary bees often visiting grass flowers, and the larger honeybees and bumblebees frequently gathering pollen from corn tassels and other grains.
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[A]: Faye

[Q]: John is a scientist. Yesterday, he conducted several tests, test A, test B, test C, test D, test E, and test F. In test A he kept a substance in solid state. Then in test B he changed the same substance to liquid state. In test C he conducted a chemical reaction in room temperature. Then in test D he conducted the same chemical reaction in higher temperature. In test E he kept some enzymes in high temperature. Finally, in test F he kept the same enzymes in lower temperature. Which test would be slower, test C or test D? Hint: Temperature is a measure of the average kinetic energy of the particles in matter. In everyday usage, temperature indicates a measure of how hot or cold an object is. Temperature is an important parameter in chemistry. When a substance changes from solid to liquid, it is because there was an increase in the temperature of the material. Chemical reactions usually proceed faster if the temperature is increased. Many unstable materials (such as enzymes) will be viable longer at lower temperatures.
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[A]: test C

[Q]: Nicholas works in pest control, and needs to have a steady supply of nitrogen gas for his tools. He always keeps a closed container of nitrogen gas in his freezer, where the temperature is very low. Nicholas's neighbor, Justin, likes to grill in his backyard. Justin, therefore, always keeps a closed container of propane gas outside, where the temperature is high. Molecules of which gas will collide against the walls of their respective container with less force? Hint: Shown in the Figure below is a cylinder of gas on the left that is at room temperature (300 K). On the right, the cylinder has been heated until the Kelvin temperature has doubled to 600 K. The kinetic energy of the gas molecules increases, so collisions with the walls of the container are now more forceful than they were before. As a result, the pressure of the gas doubles. Decreasing the temperature would have the opposite effect, and the pressure of an enclosed gas would decrease.
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[A]:
nitrogen gas