Stars begin to form from clouds of gas in space. The cold temperatures and high densities (compared to elsewhere in space, but would be considered a vacuum on Earth) of these clouds allow gravity to overcome thermal pressure and start the gravitational collapse that will form a star.
The hypothesis that all modern humans descended from an African lineage is supported by the mitochondrial DNA evidence. The Eve hypothesis is the hypothesis that is based on the study of mirtochodrial DNA; that modern humans have a common female ancestor who lived in Africa around 200,000 years ago. It is also called African Eve hypothesis.
A descriptive observation may very well be a mixture of both quantitative and qualitative as it can utilize elements of both types. Qualitative deals with the kinds of observations that cannot be measured in numerical form. Quantitative data is just that.
Transport of blood under high pressure is done through the concerted efforts of the heart and arteries.
<h2>The circulatory system is the network of the heart, arteries, veins, and capillaries responsible for the movement of blood around the body.</h2>
Transporting blood under high pressure can be explained in the following steps:
- Contraction of the heart ventricles creates blood under high pressure
- High pressured blood is removed from the heart through the arteries. In addition, the arteries are able to contract and expand, thus are elastic
- The lumen of the arteries is narrow thus helping in maintaining high pressure
As a result of the above, the high pressure of blood is maintained and transported to the extremities of the body.
To learn more about the circulatory system see: brainly.com/question/3305440?referrer=searchResults
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