<span>The formation of the fertilization envelope (slow-block to polyspermy) requires an increase in the availability of </span>calcium ions.
Slow-block to polyspermy is also called cortical reaction. In this reaction, the sperm will be permanently blocked by cortical granules. The release of calcium ion will trigger this reaction.
2 or more different atoms are combined in definite proportions in any compound.
The answer is "Tolerance only for cold climates". Hope it helped!
Answer:
An elephant and a tree are both living things. According to cell theory, what can you conclude about these two very different organisms?
The lancelets consist of approximately 32 types of
fish-like maritime chordates in the order of Amphioxiformes,
with an international dissemination in tropical seas and low temperate, they are commonly found half-buried in sand. The lancelets show 4 of the major
characteristics of the phylum chordata.
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