Answer:
the petrified log looks like the original tree.
Explanation:
A tree to be petrified first needs to be buried. An element laying on the surface can not be petrified because it is exposed to many different factors (such as<em> organisms, microorganisms, climatic conditions</em>, etc.), that affect the petrification process. So, in the case of a fallen tree, first, it needs to be covered by many sedimentary layers. Once it is underground, it also needs the presence of underground water and minerals. Water replaces the original organic material with minerals (silica, calcite, and pyrite). This replacement process results in the conversion of the woody material into a fossil of the original material. Very often, the tree details are so preserved that the fossil looks exactly like the original trunk.
Depending on the preservation degree, a fossil can be useful for different studies about the past.
Electricity is added to recharge a battery. A third phosphate group is added to ADP to form ATP.
ATP or Adenosine triphosphate contains adenine, ribose and 3 phosphate groups.
ADP is converted to ATP by the following reaction:
ADP+Pi+energy⇄ATP
The analogy between battery and ATP can be explained as ATP is higher energy form and ADP is lower energy form like charged and uncharged form of the battery. When the terminal or third phosphate is removed from the ATP it becomes ADP and releases energy like a battery. The additional phosphate group when added to ADP forms the ATP molecule like the energy spent by the batteries are recharged by putting in additional energy. Here the additional energy is provided by the third phosphate group.
Answer:
Immunity to Small Pox
Explanation:
Over the years, Europeans had built up an immunity to smallpox because many had contracted the disease and still survived. As the population grew children were born with some immunity to the disease. When the Europeans arrived in the Americas, and smallpox spread around the native peoples, the Europeans did not contract the disease because they were immune. However, since the natives were not immune, they slowly died of due just to the disease as well as some parts of the war between the europeans.