During the initial development stages of cleavage, what are the individual cells called?
1) gametes
2) blastopores
3) blastomeres

The correct answer is option 3, that is, blastomeres.

Explanation:

A kind of cell formed by cleavage of the zygote post-fertilization is called a blastomere, it is an important constituent of blastula formation. The formation of blastomere starts instantaneously post-fertilization and is carried through the initial week of the development of embryo. The division of zygote after fertilization is regarded as the first mitotic outcome of the fertilized oocyte. These mitotic divisions take place spontaneously and lead to a grouping of cells known as blastomeres.

poor water quality affects most estuarine organisms, including commercially important fish and shellfish. the pollutants that have the greatest impact on the health of estuaries include toxic substances like chemicals and heavy metals, nutrient pollution (or eutrophication), and pathogens such as bacteria or viruses.