The light would be best described as AN UNCONDITIONED STIMULUS.
An unconditioned stimulus refers to any stimulus which naturally evokes a response from the affected person. The response that is evoked is termed unconditioned response. In the question given above, the light is the unconditioned stimulus while the blinking is the unconditioned response.<span />
Answer:
Bacteria cells have no nucleus.
The two new strands are different from each other ,both of them have only one strand from the original DNA and the other strand is complementary . eg if a strand has the following base pairs .. AACCGGT ( consider this as the strands)
TTGGCCA
now they are going to be seperated AACCGGT TTGGCCA
TTGGCCT AACCGGT
as u can see the two NEW strands formed are similar but NOT IDENTICAL to each other .
I think the right answer is that it's "false"
The correct answer is: Layer 1, layer 2, and layer 4 in all three regions.
The index fossils are fossils that are commonly used for identifying a geological period of time, and these fossils are also very wide spread, as well as having a rapid evolutionary trends.
By this picture, we can easily see that even though we have rock strata from different regions, the same layers contain the same fossil, and it is a fossil that also is rapidly evolving so has a minor change in each layer.