The event that gave rise to algae was the uptake of cyanobacteria that became chloroplasts. This process of engulfing microbes that then become parts of the eukaryotic cell is known as .

Endosymbiosis

Explanation:

Endosymbiosis is a theory developed to explain the origin of eukaryotic cells from a prokaryotic origin. Organelles of the eukaryotic cells such as mitochondria and chloroplast were thought to have developed from this process.

According to this theory, a proto-eukaryote eats up or engulf a proto-mitochondrion or protochloroplast (in form of microbes) to become eukaryotic organelles such as mitochondrion and chloroplast respectively.

the principle of segregation describes how pairs of gene variants are separated into reproductive cells. from his data, mendel formulated the principle of segregation. we now know that the segregation of genes occurs during meiosis in eukaryotes, which is a process that produces reproductive cells called gametes.