OBJECTIVE LIFE SCIENCE
CELL BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Small bodies floating in cytoplasm (or attached to the endoplasmic reticulum) that make proteins
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Supports/protects cell; controls movement of substances into/out of cell; separates cell from its environment
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Stiff, rigid structure that surrounds the cell membrane to support/protect the cell
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Clear, thick, jelly-like substance inside the cell membrane that contains the other organelles
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Detailed explanation-1: -Definition. The cell membrane, also called the plasma membrane, is found in all cells and separates the interior of the cell from the outside environment. The cell membrane consists of a lipid bilayer that is semipermeable. The cell membrane regulates the transport of materials entering and exiting the cell.
Detailed explanation-2: -The cell membrane, therefore, has two functions: first, to be a barrier keeping the constituents of the cell in and unwanted substances out and, second, to be a gate allowing transport into the cell of essential nutrients and movement from the cell of waste products.
Detailed explanation-3: -In other words, plasma membranes are selectively permeable-they allow some substances through but not others.
Detailed explanation-4: -The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells.