Q: A diver's air bubbles increase in size as he approaches the surface because what decreases? Read this paragraph and choose the correct option from the provided answers: A scuba diver, like the one in Figure below , releases air bubbles when he breathes under water. As he gets closer to the surface of the water, the air bubbles get bigger. Boyle's law explains why. The pressure of the water decreases as the diver gets closer to the surface. Because the bubbles are under less pressure, they increase in volume even though the amount of gas in the bubbles remains the same. Choices: - water direction - water weight - water energy - water pressure A:
water pressure
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Q: The end result of diffusion is an equal concentration, or equilibrium , of molecules on both sides of what? Read this paragraph and choose the correct option from the provided answers: Diffusion will continue until the concentration gradient has been eliminated. Since diffusion moves materials from an area of higher concentration to the lower, it is described as moving solutes "down the concentration gradient. " The end result of diffusion is an equal concentration, or equilibrium , of molecules on both sides of the membrane. At equilibrium, movement of molecules does not stop. At equilibrium, there is equal movement of materials in both directions. Choices: - the cell - the organism - the organelle - the membrane A:
the membrane
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Q: Because it can be controlled intentionally, skeletal muscle is also called what type of muscle? Read this paragraph and choose the correct option from the provided answers: Skeletal muscle tissue forms skeletal muscles, which attach to bones and sometimes the skin and control locomotion and any other movement that can be consciously controlled. Because it can be controlled intentionally, skeletal muscle is also called voluntary muscle. When viewed under a microscope, skeletal muscle tissue has a striped or striated appearance. This appearance results from the arrangement of the proteins inside the cell that are responsible for contraction. The cells of skeletal muscle are long and tapered and have multiple nuclei on the periphery of each cell. Smooth muscle tissue occurs in the walls of hollow organs such as the intestines, stomach, and urinary bladder, and around passages such as in the respiratory tract and blood vessels. Smooth muscle has no striations, is not under voluntary control, and is called involuntary muscle. Smooth muscle cells have a single nucleus. Cardiac muscle tissue is only found in the heart. The contractions of cardiac muscle tissue pump blood throughout the body and maintain blood pressure. Like skeletal muscle, cardiac muscle is striated, but unlike skeletal muscle, cardiac muscle cannot be consciously controlled and is called involuntary muscle. The cells of cardiac muscle tissue are connected to each other through intercalated disks and usually have just one nucleus per cell. Choices: - automatic - necessary - involuntary - voluntary A:
voluntary
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Q: Diffusion is an effective transport mechanism over the spatial scales typically found at what level? Read this paragraph and choose the correct option from the provided answers: Choices: - electromagnetic - molecular - atom - cellular A:
cellular
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