A relatively small blood pressure gradient is generally insufficient to move blood through the veins under given conditions, thus venous return must be facilitated by valves within veins and two "pumps." ... As skeletal muscles contract, veins are squeezed to help propel the blood toward the heart.
Yea they actually can and l<span>iving things that are composed of one cell are known as unicellular organisms. Examples of unicellular organisms include amoebas, bacteria and certain fungi. Unicellular organisms are either prokaryotes or eukaryotes.</span>
Answer:
Anatomy
<h2>
What did the Human Genome Project accomplish?</h2>
In essence, it served as a standard for how a human genome appears. One of the first stages in determining if a mutation causes an illness is realizing that there IS a mutation. In order to compare it to "regular" human DNA sequences, we completed the human genome project. Similar to this, a human genome sequence is required in order to compare a human genome or gene to that of a dog or a fruit fly. It essentially changed us from doing genes one at a time to performing them in bulk. You can quickly trace a novel mutation or gene back to the reference genome to determine its location, typical sequence, etc.
Neanderthal genome sequencing is a nice illustration of this. In the absence of a reference genome to match it to, it was just a collection of random sequences. They were able to align and compare the reference human genome to determine precisely how humans vary from Neanderthals. That's a fascinating and significant piece of study that would not have been possible without the creation of a high-quality human reference genome.