Answer:
Blood Brain Barrier(BBB)
Explanation:
This is a biological interface of special endothelial cells of astrocytes, pericytes , capillaries, neurons and other structures, acting as a physical barrier or gate separating the Central Nervous system from the peripheral blood circulations. Thus it formed a tight junction serving as a physical barrier to selectively regulate the entrance of substances from the cerebral blood flow into the brain, therefore maintaining homeostasis of the brain.
From above any substances absorbed into the blood stream irrespective of the mode of entry are transported through the BBB, and are selectively regulated to enter the brain cells by the BBB's interactions with the blood vessels, hormones etc.
Basically it allows the passage of nutrients, a few drug, hormones and resists certain toxins and pathogens for the brain homeostasis.
I'm going to guess that it's the second option, "New matter only enters the biosphere in the form of precipitation" because it bothers me that the writer said "new matter" and everything else seemed right to me.
The last two are definitely true. I'm a bit iffy about the first option because I know that autotrophs take the energy from the sun, then primary consumers eat them and then everything eats one another afterwards. So everything moves from the bottom of the food pyramid up. There are decomposers which take dead matter from any trophic level and bring it up, which, I guess, is still in the same direction on the food pyramid.
New matter can probably enter the biosphere in other ways like a meteor hitting the earth or something. The water from precipitation never left the biosphere, so that's where it's wrong.
I hope this helps.
Answer:
The funny thing is that the water that falls from the sky as rain today, might have fallen last week, last month, last year or thousands of years ago. It is the greatest recycler of all time! There are four main stages in the water cycle. They are evaporation, condensation, precipitation and collection.
Answer:
the root system in mesophytes possesses well-developed roots (generally grow deep inside the soil), providing anchorage to the plants. It also allows efficient water and mineral absorption from the surrounding soil.
Explanation:
i hope this helps<3
:)
Hello.
The answer is S<span>upernova.
A supernova happends at the end of the stars lifetime. So its baslical the death of a star but it could lead to causing a blackhole. </span><span>A supernova leaves the core of the star to collapse into a neutron star or black hole, but still most of the star is disrupted, not just the outer portion.
Have a nice day</span>
