Individual and public health are affected by environmental and genetic factors is a statement which reflects reality. Firstly, susceptibility to certain diseases usually or often runs in a family so that if there is say, diabetes in the father and grandmother for example, the son or daughter has more chances of getting it so this is a genetic susceptibility.. Also, some families are more prone to cancer so that given the right circumstances, cancer can develop. So it is usually a combination of both genetic and environmental causes that results in a disease. An example of public health could be when smallpox was deliberately introduced to the First Nations people in British Columbia, Canada back in the 1800's to decimate them and remove their resistance to the gold mining hordes. Since the First Nations had no anti-bodies to counteract such a disease unlike the white men who introduced it to them, then they easily fell prey to it and died within days of contracting it.
<span>A cell with a large surface area or with microvilli (which increase surface area) are specialized for absorption. Many cells have different protein markers on their surface to accept certain specific hormones and allow them into the cell, like muscle cells reacting to adrenaline. Muscle cells are long and able to contract, allowing for overall muscle contraction and body movement. </span>
<span>I guess the hormone part I mentioned applies to chemicals; endocrine cells produce hormones that other cells would not. </span>
<span>For organelles, muscle cells don't have many of the organelles that other cells do because of their very specialized functions. </span>
<span>I hope this helps, it would literally take volumes of text books to answer this question completely.</span>
They could discover which organisms are closely related to the mammoth, and which one is the most closely related.
