Answer the following question given this paragraph: U92235 + n01®️ B56141a + K3692r + 3n01 This hypothesis was confirmed by detecting the krypton-92 fission product. As discussed in Section 20.2 "Nuclear Reactions", the nucleus usually divides asymmetrically rather than into two equal parts, and the fission of a given nuclide does not give the same products every time. In a typical nuclear fission reaction, more than one neutron is released by each dividing nucleus. When these neutrons collide with and induce fission in other neighboring nuclei, a self-sustaining series of nuclear fission reactions known as anuclear chain reaction can result (Figure 20.16 "The Curve of Nuclear Binding Energy"). For example, the fission of 235U releases two to three neutrons per fission event. If absorbed by other 235U nuclei, those neutrons induce additional fission events, and the rate of the fission reaction increases geometrically. Each series of events is called a generation. Experimentally, it is found that some minimum mass of a fissile isotope is required to sustain a nuclear chain reaction; if the mass is too low, too many neutrons are able to escape without being captured and inducing a fission reaction. The minimum mass capable of supporting sustained fission is called the critical mass. This amount depends on the purity of the material and the shape of the mass, which corresponds to the amount of surface area available from which neutrons can escape, and on the identity of the isotope. If the mass of the fissile isotope is greater than the critical mass, then under the right conditions, the resulting supercritical mass can release energy explosively. The enormous energy released from nuclear chain reactions is responsible for the massive destruction caused by the detonation of nuclear weapons such as fission bombs, but it also forms the basis of the nuclear power industry. Nuclear fusion, in which two light nuclei combine to produce a heavier, more stable nucleus, is the opposite of nuclear fission. As in the nuclear transmutation reactions discussed in Section 20.2 "Nuclear. Q: What is the minimum mass capable of supporting sustained fission called? Choices: - concentrated mass - baseline mass - particular mass - critical mass A:
critical mass
(Question)
Answer the following question given this paragraph: Fertilization is the union of a sperm and egg, resulting in the formation of a zygote. Q: Fertilization is the union of a sperm and egg, resulting in the formation of what? Choices: - a cytoplasm - a nuclei - a bacteriophage - a zygote A:
(Answer)
a zygote
Ques: Answer the following question given this paragraph: Ions such as sodium (Na + ), potassium (K + ), calcium (Ca 2+ ), and chloride (Cl - ), are important for many cell functions. Because they are charged (polar), these ions do not diffuse through the membrane. Instead they move through ion channel proteins where they are protected from the hydrophobic interior of the membrane. Ion channels allow the formation of a concentration gradient between the extracellular fluid and the cytosol. Ion channels are very specific, as they allow only certain ions through the cell membrane. Some ion channels are always open, others are "gated" and can be opened or closed. Gated ion channels can open or close in response to different types of stimuli, such as electrical or chemical signals. Q: Because they are charged (polar), these ions do not diffuse through what? Choices: - substrate - cell wall - protein - membrane A:
Ans: membrane
(Q).
Answer the following question given this paragraph: Air pollution may also cause acid rain. This is rain that is more acidic (has a lower pH) than normal rain. Acids form in the atmosphere when nitrogen and sulfur oxides mix with water in air. Nitrogen and sulfur oxides come mainly from motor vehicle exhaust and coal burning. Q: Acid rain may be caused by what? Choices: - hurricanes - water pollution - volcanos - air pollution A:
(A).
air pollution
Ques:Answer the following question given this paragraph: El Nino and La Nina bring about dramatic changes in climate for a year or two. In some locations, one brings rain and the other brings drought. In California, for example, El Nino years are full of snow and rain. La Nina years tend toward drought. These variations can bring tremendous changes to living creatures. Humans are also affected; for example, erosion from storms may be very high some years. Q: What kind of weather change do la nina years usually bring? Choices: - heat - Mass amounts of snow - moisture - drought A:

Ans:drought
Question: Answer the following question given this paragraph: Q: Crowding and resource limitation can have a profound effect on the rate of what? Choices: - population stagnation - technology advances - cultural advances - population growth A:
Answer:
population growth