Answer:
This means that the two separate rocks were once part of one piece of rock. These layers got separated most probably by continental drift as a result of tectonic plate movements. An example of such a fossil is the Mesosaurus, a freshwater crocodile-like reptile, that is found in Southern Africa and Eastern South America continents- that means they were once one land mass.
The environment in these two separate layers would most likely be different. As the layers drift apart from each other , they drift across latitudes that are determinants of climate in a region. Therefore, even the organisms in these two rock layers will evolve differently (even though they will share a common ancestor) in adaptation to respective environments – this is called allopatric speciation.
Answer:
The return of blood to the heart is assisted by the action of the skeletal- muscle pump. As muscles move, they squeeze the veins running through them. Veins contain a series of one-way valves, and they are squeezed, blood is pushed through the valves, which then close to prevent backflow.
Answer:
Hi, um. Sorry to tell you this but..
Explanation:
I don't think anyone is willing to do your project you have to do. After all, You are a middle schooler and have the ability yourself, so please, Braily is for simple questions not projects. Now, if you would mind, please finish the project..YOURSELF,and then ask other questions if needed. Tysm xx Casey
Caffeine works as an adenosine receptor antagonists, this essentially means that it works in the opposite manner or works against the receptor. Think of antagonist in the term of literature it goes against the agonist. Adenosine when bond to the receptor causes tiredness, this is the reason why people drink caffeine to stay wake and to prevent cognitive decline from exhaustion. So caffeine doesn’t really effect learning or memory to a large extent like other stimulants do. So basically caffeine increases wakefulness which in turn allows a person to focus longer, slight increase in memory, and more of a sorted out thought process.
