There are all sorts of ways to reconstruct the history of life on Earth. Pinning down when specific events occurred is often tricky, though. For this, biologists depend mainly on dating the rocks in which fossils are found, and by looking at the “molecular clocks” in the DNA of living organisms.
There are problems with each of these methods. The fossil record is like a movie with most of the frames cut out. Because it is so incomplete, it can be difficult to establish exactly when particular evolutionary changes happened.
Modern genetics allows scientists to measure how different species are from each other at a molecular level, and thus to estimate how much time has passed since a single lineage split into different species. Confounding factors rack up for species that are very distantly related, making the earlier dates more uncertain.
These difficulties mean that the dates in the timeline should be taken as approximate. As a general rule, they become more uncertain the further back along the geological timescale we look. Dates that are very uncertain are marked with a question mark.
If iodine solution reacts with starch, it will change color into black.
Since the yellow-orange iodine solution stayed the same <span>color when it was put on the apple, it can be concluded that there is no starch in the apple. On the other case, the black color of the potato suggests that there is a great amount of starch in the potato. Anyway, this does not mean that there is no starch in the apple at all. As fruits ripen, starch slowly changes to sugar. Iodine cannot react with sugar, so the black color in the apple is missing.</span>
Answer: Breaks down, decomposes. Decomposers include bacteria and fungi.
No picture is shown in your question
Answer:
16/25
Explanation:
0.640 = 640
____, cancelling one zero, we have
1000
= 64
___, cancelling by 4, we have
100
= 16
___
25
