By Forming Over 100 Pinocytic Vesicles Per Minute, a Macrophage

question 31

Short Answer

By forming over 100 pinocytic vesicles per minute, a macrophage ingests over 10% of its own volume of fluid every half an hour. This is equivalent to ingesting about 100% of the macrophage's plasma membrane. If the average volume of a macrophage is about 450 µm³ and its average surface area is about 750 µm², what is the average diameter of the early pinocytic vesicles in the cell? Assume spherical vesicles. The formulas for the volume (V) and surface area (S) of a sphere of radius r are V = 4/3 × ? × r³, and S = 4 × ? × r², respectively. Write down your answer in nanometers, with no decimals, e.g. 830 nm.

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Long-term tangible property owned by a business, intended for use in the production of income and not quickly converted into cash.

Plant Asset

Long-term tangible assets used in the operations of a business that are not intended for sale.

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The act of getting rid of an asset through sale, exchange, retirement, or destruction.

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