Detail how the dorsal: ventral axis is established in amphibia, from the importance of the sperm entry point to the gene regulation in the dorsal area of the entryo

Explanation: Amphibian axis formation is an example of regulative development. The most important clue came from the fate map of this area of the egg, for it. Therefore, the specification of the dorsal-ventral axis begins at the moment of sperm entry.  The Siamois protein is critical for the expression of organizer-specific genes

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products

the contamination

we are putting to many trash.