Experiments Results: Sea Urchin, Sea star and Frog.
- Sea urchin and Sea star have holoblastic cleavage. As the number of cells increases, the size of cells decreases.
- The jelly coat of an echinoderm egg slowly dissolves in water and releases molecules that allow spem to penetrate and fertilization begins.
- Sea star and urchin have equal size of cells because yolk is evently distributed and have isolecithal eggs.
- Amphibians have moderately telolecithal eggs and holoblastic cleavage.
- A yolk plug forms in the blastopore.
- Neurulation forms a dorsal hollow nerve cord.
- They have unequal size of cells, the ones containing more yolk are larger.