Answer the following question given this paragraph: It can be really exciting to explore a big underground cave like the one in this picture. Do you know how caves form? Believe it or not, water is the answer. Water slowly dissolves rocks, especially certain types of rocks such as limestone. How does something as mild and harmless as water cause hard rocks to dissolve? In this chapter, you'll find out. Q: Caves form over time when what causes rocks like limestone to dissolve? Choices: - weather - acid - air - water A:
water
Answer the following question given this paragraph: Punta Arenas, Chile is the world's most southern city. At such a high latitude, winters are exceedingly cold and dark. Unlike the children pictured above, the children in Punta Arenas must stay inside to avoid the cold. Of course, they look forward to spring when they can go out to play. But some years, it is too dangerous for the children to go outside. The ozone hole has moved north. Too much of the Sun's harmful UV radiation gets through. Q: In some parts of the world, too much of the sun's harmful uv radiation gets through because of a hole in what layer? Choices: - mesosphere - troposphere - thermosphere - ozone A:
ozone
Q: Answer the following question given this paragraph: or myotube. As a myotube is formed from many different myoblast cells, it contains many nuclei, but has a continuous cytoplasm. This is why skeletal muscle cells are multinucleate, as the nucleus of each contributing myoblast remains intact in the mature skeletal muscle cell. However, cardiac and smooth muscle cells are not multinucleate because the myoblasts that form their cells do not fuse. Gap junctions develop in the cardiac and single-unit smooth muscle in the early stages of development. In skeletal muscles, ACh receptors are initially present along most of the surface of the myoblasts, but spinal nerve innervation causes the release of growth factors that stimulate the formation of motor end-plates and NMJs. As neurons become active, electrical signals that are sent through the muscle influence the distribution of slow and fast fibers in the muscle. Although the number of muscle cells is set during development, satellite cells help to repair skeletal muscle cells. A satellite cell is similar to a myoblast because it is a type of stem cell; however, satellite cells are incorporated into muscle cells and facilitate the protein synthesis required for repair and growth. These cells are located outside the sarcolemma and are stimulated to grow and fuse with muscle cells by growth factors that are released by muscle fibers under certain forms of stress. Satellite cells can regenerate muscle fibers to a very limited extent, but they primarily help to repair damage in living cells. If a cell is damaged to a greater extent than can be repaired by satellite cells, the muscle fibers are replaced by scar tissue in a process called fibrosis. Because scar tissue cannot contract, muscle that has sustained significant damage loses strength and cannot produce the same amount of power or endurance as it could before being damaged. Smooth muscle tissue can regenerate from a type of stem cell called a pericyte, which is found in some small blood vessels. Pericytes allow smooth muscle cells to regenerate and repair much... Q: As a myotube is formed from many different myoblast cells, it contains many nuclei, but has a continuous what? Choices: - nucleus - mucus - cerebellum - cytoplasm A:
A: cytoplasm
Question: Answer the following question given this paragraph: Evolution focuses on past life forms and how they turned into present life forms. The history of life on Earth demonstrates how the first cells formed, turned into simple life forms, and then became more complex plants and animals. The studies of Charles Darwin have reshaped and influenced all aspects of biology. The vast amounts of evidence of evolution demonstrates the importance of the theory of evolution by natural selection. But has this process stopped? Of course not. Evolution does continue today. Q: What theory of evolution is charles darwin most known for? Choices: - natural change - natural variety - immoral selection - natural selection A:
Answer: natural selection
*Question*
Answer the following question given this paragraph: Q: What is the process by which undigested food leaves the body? Choices: - glycolysis - digestion - peristalsis - egestion A:
**Answer**
egestion
*Question*
Answer the following question given this paragraph: A mineral is a solid material that forms by a natural process. A mineral can be made of an element or a compound. It has a specific chemical composition that is different from other minerals. One mineral's physical properties differ from others'. These properties include crystal structure, hardness, density and color. Each is made of different elements. Each has different physical properties. For example, silver is a soft, shiny metal. Salt is a white, cube-shaped crystal. Diamond is an extremely hard, translucent crystal. Q: A mineral can be made of an element or a? Choices: - Sediment - component - cell - compound A:
**Answer**
compound