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.
Lets say that the genotypes are:
Male affected:XbY
Male unaffected: XaY
Female affected: XbXb
Female carrier: XaXb
Female unaffected:XaXa
P: XbY x XaXa
F1: XaXb XaXb XaY XaY The middle square is female carrier.
P:XbY x XaXb
F1: XaXb XbXb XaY XbY The left square is affected female.
P:XaY x XbXb
F1: XaXb XaXb XbY XbY The right square is affected male.
They have more little impact because they are renewable
Answer:
algae. I just looked it up. algae are autotrophs meaning they make their own food. I hope this helps!
I think it is A
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