Answer:
So there's a simple explanation for the Great Oxidation Event. It was the cyanobacteria, pumping out unwanted oxygen, that transformed Earth's atmosphere. ... That means the cyanobacteria were busy pumping out oxygen for at least half a billion years before oxygen started appearing in the air.
Explanation:
The Rat’s whiskers are highly sensitive to touch, they brush over the ground, obstacles, food, and other rats. When they bend, it’s follicles send messages to the rat’s brain.
The Rat’s incisors are the four long, sharp front teeth, they use them for gnawing and for grinding food prior to swallowing it.
I would say D narrow temperature. Most other planets are too hot or cold to sustain life.
Answer:
5%
Explanation:
The adrenal cortex in both males and females produce a small amount of weak androgens. One of the major weak androgen secreted by adrenal cortex is dehydroepiandrosterone (DHEA).
Levels of dehydroepiandrosterone secretion exhibit changes with age. The dehydroepiandrosterone secretion increases till the age of 20-24 years and falls off with increasing age after the age of 30 years in both males and females. The DHEA production at the age of 80 years is about 5% of its secretion at the age of 30 years.