Answer:
C.
Explanation:
Nitrogen fixation is a process by which molecular nitrogen in the air is converted into ammonia or related nitrogenous compounds in soil. Atmospheric nitrogen is molecular dinitrogen, a relatively nonreactive molecule that is metabolically useless to all but a few microorganisms.
Competition requires instant succession within organism but parasitism can still be a gradual process due to its types exo and endo
THE ANSWER IS COMPETITION
Answer:
In North America, around June 21, Earth tilts on its axis toward the sun, which is Summer Solstice and when the Northern Hemisphere has the most daylight of any time of year. Winter solstice the Northern Hemisphere tilts the farthest away from the sun and when we have the least amount of daylight of any time of the year.
Explanation:
As Earth revolves around the Sun, it rotates on its axis. Sometimes Earth tilts toward the Sun which is when Summer occurs. In the Winter Earth tilts away from the Sun.
False
Sedimetary rocks can be formed from changes in igneous rock, and igneous rock can be from changes in sedimentary rock.
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.
