Just think about cancer.. it's uncontrolled cell growth, so mutations in genes can cause cancer by accelerating cell division. As the cells contribute to grow they then develop as a tumor.
Answer:
Brain stem
Explanation:
The cerebellum is key to maintaining balance and coordination, not involuntary actions such as breathing.
The frontal lobe of the brain is responsible for things like emotions, memory, and language. Not breathing and consciousness. Plus, the frontal lobe is at the front of your brain, and you hit the back of your head.
But the brain stem is responsible for breathing, swallowing, heart rate, consciousness, and other involuntary actions your body does.
What seems to fit in the blank would be "offspring,'' but that wouldn't be true.
As countries began to have better technology, people began to have less children. Before, almost as many children died as were born, but with better healthcare, most survived, lowering the necessity for many children.