According to endosymbiosis, what is the best explanation about how eukaryotic cells evolved? Bacteria that were capable of photosynthesis engulfed smaller, heterotrophic bacteria.
Cells that did not fully separate during cellular division fused, forming larger organisms.
Chloroplasts and mitochondria were once prokaryotes that began to live within larger cells.
Two or more prokaryotes fused to form larger, multicellular organisms.

answer: - few nutrients

high pressure

low temperatures

explanation: 1. few nutrients:   open-ocean zone is located way far from the land, which is the main source of the essential nutrients.2. high pressure: pressure increases by 1 atmosphere for every 10 meters increase in depth.3. ample sunlight: a large fraction of the sunlight is reflected back to the atmosphere from the sea surface. 4. varying salinity: below the thermocline, the water is isolated from the atmosphere so the salinity remains stable over the year.5. low temperatures:   the temperature of open-ocean zone ranges from a low of -2°c to an average of 17°c

examples of nucleic acids are deoxyribonucleic acid (dna) and ribonucleic acid (rna).