Answer the following question given this paragraph: Water, carbon dioxide, and oxygen are important agents of chemical weathering. Q: Water, carbon dioxide, and what other element are important agents of chemical weathering? Choices: - helium - methane - sulfur - oxygen A:
oxygen
(Question)
Answer the following question given this paragraph: How Viruses Infect Specific Organs Specific glycoprotein molecules exposed on the surface of the cell membranes of host cells are exploited by many viruses to infect specific organs. For example, HIV is able to penetrate the plasma membranes of specific kinds of white blood cells called T-helper cells and monocytes, as well as some cells of the central nervous system. The hepatitis virus attacks only liver cells. These viruses are able to invade these cells, because the cells have binding sites on their surfaces that the viruses have exploited with equally specific glycoproteins in their coats. (Figure 3.19). The cell is tricked by the mimicry of the virus coat molecules, and the virus is able to enter the cell. Other recognition sites on the virus's surface interact with the human immune system, prompting the body to produce antibodies. Antibodies are made in response to the antigens (or proteins associated with invasive pathogens). These same sites serve as places for antibodies to attach, and either destroy or inhibit the activity of the virus. Unfortunately, these sites on HIV are encoded by genes that change quickly, making the production of an effective vaccine against the virus very difficult. The virus population within an infected individual quickly evolves through mutation into different populations, or variants, distinguished by differences in these recognition sites. This rapid change of viral surface markers decreases the effectiveness of the person's immune system in attacking the virus, because the antibodies will not recognize the new variations of the surface patterns. Q: The hepatitis virus attacks only cells of what organ? Choices: - lungs - kidney - brain - liver A:
(Answer)
liver
Ques: Answer the following question given this paragraph: Pinocytosis or "cellular drinking," occurs when the plasma membrane folds inward to form a channel allowing dissolved substances to enter the cell, as shown in Figure below . When the channel is closed, the liquid is encircled within a pinocytic vesicle. Q: Pinocytosis or "cellular drinking," occurs when the plasma membrane folds inward to form a channel allowing dissolved substances to enter what? Choices: - proteins - nucleus - homeostasis - cell A:
Ans: cell
(Q).
Answer the following question given this paragraph: Fission is the opposite of fusion and releases energy only when heavy nuclei are split. As noted in Fusion, energy is released if the products of a nuclear reaction have a greater binding energy per nucleon ( BE / A ) than the parent nuclei. Figure 32.25. Q: What process is the opposite of fusion and releases energy only when heavy nuclei are split? Choices: - activation - osmosis - diffusion - fission A:
(A).
fission
Ques:Answer the following question given this paragraph: The heating curve shown is for water but other substances have similarly shaped heating curves. Suppose you begin with solid water (ice) at -30C and add heat at a constant rate. The heat you add in the beginning will be absorbed as kinetic energy and the temperature of the solid will increase. When you reach a temperature of 0C (the melting point for water), the heat you add is no longer absorbed as kinetic energy. Instead, the added heat is absorbed as potential energy and the particles separate from each other. During the flat part of the curve labeled "melting", heat is being added constantly but the temperature does not increase. At the left edge of this flat line, the water is solid; by the time enough heat has been added to get to the right edge, the water is liquid, but maintains the same temperature. Once all the water is in the liquid form, the added heat will once again be absorbed as kinetic energy and the temperature will increase again. During the time labeled "water being heated as a liquid", all the added heat is absorbed as kinetic energy. Q: In what form is the heat absorbed when you heat ice and it reaches a temperature of 0 c? Choices: - geothermal energy - mechanical energy - radiation energy - potential energy A:

Ans:potential energy
Ques:Answer the following question given this paragraph: The thermosphere is the layer above the mesosphere. It rises to 600 kilometers (372 miles) above the surface. The International Space Station and other space stations orbit Earth in this layer. Q: What is the name of the layer above the mesosphere? Choices: - exosphere - lithosphere - intersphere - thermosphere A:

Ans:
thermosphere