Answer: Because they have built up immunity from past medications.
Explanation: As people get sick and are given antibiotics the 99.9 % are removed but that one percent from the bacteria is able to overcome the antibiotics and make itself stronger and immune to the medicines, then the bacteria evolves and a new person will get infected and will need stronger antibiotics further more the cycle is repeated.
A mutation is a change in trait. For example people who are lactose intolerant are normal, but people that can can drink milk without a problem have mutated. Hopefully this makes sense and helped.
I think sister groups. Imagine them having the same parents.
Parent rocks.
( I got it wrong when I put Inorganic materials)
Of the total amount of glucose energy consumed by the body each day, about 20% is used by the brain and nerve cells.
The brain constitutes about 2% of the total body but it is one of the main consumers of energy derived from glucose.
The energy provided by glucose is used for the proper functioning of the brain. It generates ATP which is an energy source that is responsible for r neuronal and non-neuronal cellular maintenance and generates neurotransmitters.
Thus glucose-derived energy is critical for the health of the brain. Lack of energy can cause several brain diseases.
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