Answer:
False
Explanation:
Humans all around the world has a body temperature similar, humans like all the mammals are endothermic (the body temperature is regulated for itself) animals, this means that our temperature doesn't change according to the climate.
Also the flow of the blood in our body changes according to the heart rate, while more bits per second our heart does, more blood flows in our extremities.
So it's false that human evolved in colder have more blood flowing into their extremities, and at a hotter temperature, than people living in warmer climates.
A controlled variable is a commonly used term in the field of scientific research, where finding evidence to support a theory is rarely straightforward. In the case of the natural sciences, some research features are constant, but the majority of these have inconsistencies. These inconsistencies are known as variables.
Having a karyotype done is important to detect crucial diseases such as Trisomy 13, Trisomy 21, Klinefelter's Disease, and Turner syndrome.