Although the actual questions are missing from your ask, here's how you can tell.
If the study will be messed up (added bias) through interaction with the subjects the study should be observational. For example if a biologists wanted to study the eating habits of wild birds in the tropics, they would need to do an observational study. if they did a controlled experiment, the birds will change their eating habits based on human interaction, thus making the study invalid.
If the study requires specific measurements, close monitoring, or contact and interaction with the subjects the study should be a controlled experiment. For example, if a scientist wanted to test out a new drug, the health of patients would need to be closely monitored.
<span>The question says,'decomposition of plants and animal matter present in the soil is largely due to soil micro organism. The statement is true. The soil microbes function by decomposing the organic matter in the soil to the forms usable to plants. The humus produce by these microbes is largely responsible for soil fertility. </span>
Answer:
This process would be the one truly responsible for the "evolution" of mitochondria and chloroplasts as we know them from their prokaryotic ancestors. The cell process that would have initiated endosymbiosis is endocytosis; the process of taking things inside the cell
A Venus flytrap produces new leaves from the step tip. <span>The life characteristic that this illustrates is A. Growth. </span><span>Venus Flytraps are composed only of leaves, and rather than sharing a root system, each leaf grows its own root or roots, and each root is a single structure, not dividing or </span>
Four new haploid cells are formed once the sister chromatids within the two daughter cells separate, forming four new haploid gametes.