The four limitations are
1.It's often impossible to repeat trials on the same subjects.
2-Subjects may report an inaccurate medical history.
3-It can be difficult to control all possible variables.
4-It's impossible to come up with testable scientific questions for human subjects.
Research involving human beings is ultimately necessary for improvements in human health and welfare. Any results about healthy physiology, illness causes, treatment effectiveness, learning, or behavior must be verified by carefully controlled investigations involving human participants. Sadly, not all human research have been valid and beneficial. It is possible to harm people in the name of research. The most well-known instances happened in Nazi Germany. Investigations conducted after the war found several crimes, including experiments in which participants were submerged in extremely cold water to determine how long it would take them to pass away from hypothermia.
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The answer is; the skeletal system and the nervous system
The skeletal system (muscle and bone) give you rigidity and enable your legs to support your weight. The muscles also act on the bone as a fulcrum allowing it possible for them to contract and make motion possible.
The nervous system is important in the coordination of movement. The brain is the center for locomotor action. This ensures you are able to place one foot in front of the other in sequence and moving your arm in concert.
Cell wall won’t be found in a animal cell since it’s only there in a plant cell.
Hey bud, this is not a question someone can answer. Try giving us the drop down menu stuff?
