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The photo below shows an early frog embryo after three mitotic divisions of a fertilized egg. This embryo has how many cells?

The photo below shows an early frog embryo after three mitotic divisions of a fertilized-example-1
User Klanm
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1 Answer

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This embryo has 8 cells.

Step-by-step explanation:

  • Just after fertilisation the embryo under goes cleavage.
  • In frog, the first division takes place at the vegetal pole .
  • Before the first division completes the second division begins at the animal pole, at right angles to the first division.
  • At this stage the embryo has four cells.
  • The third division occur at the equitorial plane, but slightly towards the animal pole.
  • this third division divides the embryo into two regions: a ) rapidly dividing dividing region of micromeres b) slowly dividing region of macromeres.
  • after third division there are 4 micromeres towards the animal pole and 4 macromeres at the vegetal pole.
User Philippe Grondier
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