Final answer:
An observational study observes subjects and measures variables without manipulation, while an experimental study actively manipulates the variables and measures the effects compared to a control group. Observational studies are generally more cost-effective and ethical for certain research questions, but they need careful handling to avoid observer bias.
Step-by-step explanation:
Differentiating between observational and improvisational studies is significant in understanding research methodologies in biology. An observational study does not manipulate the variables but rather observes subjects as they are. This can range from simple opinion polls to complex studies observing the effects of smoking on lung cancer without actively subjecting participants to smoke. Observational studies are known to be more cost-effective and can encompass a larger subject pool than an experimental study. On the other hand, an experimental study involves the deliberate manipulation of variables, such as administering a new drug to a group and observing the outcomes, while comparing them with a control group.
There are also specific types of observational studies, such as cross-sectional, case-control, and cohort studies, each with its advantages and disadvantages. The main challenge in observational research is to avoid observer bias, ensuring that data collection is objective and consistent. In contrast to experimental research, where the conditions are set by the researchers, observational studies document naturally occurring phenomena and are crucial when experiments are unethical or impractical.