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Course: AP®︎/College Biology > Unit 2

Lesson 2: Cell size
Science
AP®︎/College Biology
Cell structure and function
Cell size
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Cell size

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Problem

An oocyte is an immature reproductive cell found in many sexually reproducing organisms. A crawfish oocyte has a radius of approximately 1mm, while a human oocyte is much smaller and has a radius of about 0.05mm.
Surface area of a sphere: A=4πr2
Assuming both cell types are perfectly spherical, how many times larger is the surface area of a crawfish oocyte compared to the surface area of a human oocyte?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
times