Answer:
While it is difficult to determine exactly how many Natives lived in North America before Columbus, estimates range from a low of 2.1 million to 7 million people to a high of 18 million.
Explanation:
<span>The ischemic penumbra can maintain metabolic demand with marginal blood flow from collateral circulation for a maximum of 50% before increasing in size. A penumbra is the area where the flow of blood at about 25 - 50% can maintain normal metabolic demands for 6 - 8 hours only. When it continues to increase, the human cells will die and other neurological activity will be suspended causing the person to die slowly.</span>
Answer: Sickle cell disease is caused by a mutation in the hemoglobin-Beta gene found on chromosome 11. Hemoglobin transports oxygen from the lungs to other parts of the body. Red blood cells with normal hemoglobin (hemoglobin-A) are smooth and round and glide through blood vessels.
Explanation:
The correct answer is "limited prey is driving the bears to seek food in human settlements".
Due to the warming of the Arctic waters, the ice is melting, resulting in a serious decline of floating winter ice. Polar bears need these floating parts of ice to hunt, therefore this new situation limits the hunting opportunities of the bears. That is why polar bears are driven to human settlements to look for food.
A cell or Atom is something that can process life or can processed into an object. (The atom is in objects and life Such as animals and humans as a cells in just humans and animals
