Answer:
There is no actual way that the mantle could be...'exposed' or 'seen'. But scientists have managed to find multiple ways to analyze the mantle and it's actual existence by using multiple devices. The mantle is basically a 2,900 kilometers (1,802 miles) thick blocks of rocks and minerals underneath the crust(or the surface of the earth) , and makes up a whopping 84% of Earth's total volume.
During DNA Replication, the DNA molecule unzips itself so that there are two free strands of DNA. Both of those strands then create new complementary strands of DNA. Thus every subsequent generation of DNA uses one of the parent cell's strand of DNA as a template, which is why DNA replication is said to be semi-conservative. Hope this helped!
→ Darwin believed that the need to adapt, in similar words, the changes occruing in the environment caused evolution.
The main cause of evolution, according to Darwin, was natural selection. Natural selection is a process in which a group of organisms with certain characteristics survive and thrive, in comparison to other organisms with different characteristics. This idea basically means that having some characteristics makes you suited for an environment.
And how would that ↑ explain Evolution?
Well, evolution is the change in species that occurs during time. But for you to change, there must be a cause for that change, which is none other than the need to survive, reproduce, etc.
→ As mentioned before, not all characteristics are enough to surive, and hopefully the image pasted below will help you.
Hope it helped,
BioTeacher101
Ecosystem: a biological community of interacting organisms and their physical environment.
Answer: Less Negative/ More Positive
(Either will work)
Explanation:
If the membrane potential of a neuron decreases, the membrane potential <u>less negative/more positive</u>.