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.
Answer: C
one grade level because they made up many groups of students
An ecosystem is a self supporting system in which there is a flow of materials and energy.
<h3>What is an ecosystem?</h3>
An ecosystem is a self supporting system in which there is a flow of materials and energy.
Let us now see the role of each organism in the small ecosystem.
- flower - producer
- butterfly - primary consumer
- bird - secondary consumer
- earthworm - decomposer
Learn more about ecosystem: brainly.com/question/13979184
Veins provide support for the leaf and transport both water and minerals (via xylem) and food energy (via phloem) through the leaf and on to the rest of the plant.
there are 88 constellations in total
