Answer :There was enough oxygen in the atmosphere to support a major burst of life on Earth
Explanation:
The Great Oxygen Event marks the time, approximately 2.5 billion years ago, when there was enough oxygen in the atmosphere to support a major burst of life on Earth
For the first half of the Earht's history, there was no oxygen in the atmosphere. It was inhabited only by single-celled organisms.Of those simple life forms, the cyanobacteria may have. evolved a way to take energy from sunlight, and used it to make sugars out of water and carbon dioxide. They used the same chemical process we know as photosynthesis. This released vast quantities of oxygen into the atmosphere and triggered the evolution of complex life.
It results in the a narrowing of the arteries which slow blood flow
It’s A the immune system & lymphatic Hope this helps!
Answer:
B) sympathetic nervous system
Explanation:
The sympathetic nervous system controls the way the body quick involuntary response to harmful or stressful situations. A rush in hormones rapidly occur to quicken the body's alertness and heart rate to release extra blood to the muscles
It's route of Expression starts with the amygdala sending a distress signal to the hypothalamus which sends activation signals to the sympathetic nervous system via the autonomic nerves to the adrenal glands which help pump the hormone epinephrine (also known as adrenaline) into the bloodstream.