Answer:
It is normal for there to be veins visible underneath the tongue, partly because the mucous membrane is so thin and translucent in this region, but where these vessels become dilated and tortuous, they may appear round and black like caviar.
number 2 is for question 1
number 1 is for question 3
number 4 is for question 2
number 3 is for question 4
Explanation:
In humans, the brain accounts for ~2% of the body weight, but it consumes ~20% of glucose-derived energy making it the main consumer of glucose (~5.6 mg glucose per 100 g human brain tissue per minute.
Ask google, it’ll tell you