<h2>540 million years ago
</h2>
Paleozoic.
Era immediately follows Precambrian It lasted about 4.5 billion years.
When did abundant fossil evidence first appear in the geologic record.
540 million years ago.
Answer: true
Explanation: In gel electrophoresis, the smaller the size/molecular weight of DNA the faster it moves across the gel and vise versa. This is as a result of the pore size of the gel which is usually prepared 1g of agarose in 100ml of distilled water. So a DNA fragment with 1000 base pairs will "struggle" its movement across the gel pore making it mive less faster and further. Movement and molecular weight of DNA are inversely proportional.
Answer:
They were not around at that time or either from it being so hot they just disappeared/melted.
Explanation:
Answer:
The correct answer is "a well-developed notochord".
Explanation:
The missing options for this question are:
A) paired fins
B) jaws
C) a well-developed notochord
D) a rasping tongue
The correct answer is option C) "a well-developed notochord".
Lampreys and hagfishes are two species of jawless fish that are uncommon to see, but they have more than 30 different species for each one of them. Both lampreys and hagfishes have a well-developed notochord, during their larvae and adult forms. The notochord provides support to their body as it has the function of a cartilaginous skeleton.
