Answer:
When a research is conducted and results are deduced, scientists tend to perform the experiments again and again to check if the results are similar each time. These multiple set of research again and again is important to check and prove that our results are authentic.
Sometimes, it might happen that there might be some other external factor due to which the results are occurring as seen. Re-checking of the results s important so that it might be made sure that no external factor is the reason of the shown results.
I can answer the third one:
Photosynthesis takes place in two stages<span>: light-dependent reactions and the Calvin cycle (light-independent reactions).</span>
Answer:
1) they would need a host or vessel to stay on and feed of of their body
2) they would need some for of reproduction in the host ( mitosis whatever the algae my use )
3) they would need to wisely choose there hosts and of what they feed on so there host doesn’t die quickly
I don’t know if this is what your looking for but these are 3 things that algae would need to live
Eukaryotic chromosomes contain both DNA and protein tightly packed together to form Chromatin.