This is the exact answer:
Bacteria are helpful because they produce oxygen, which our bodies need to breathe, and they help us to digest the food we eat. Bacteria are also helpful because they are used in medicine to help us overcome disease. Bacteria are harmful because they can cause tooth decay and illnesses that can be either common or quite serious.
Extinction of species reduces the number of different species in ecosystems, hence lowering the diversity of living things.
Answer:
Mass doesn't change no matter where you are or where you go.
Explanation:
Mass is what you or an object consist of. You cant change mass
That is correct, a good description of the HYPODERMIS. Hence many syringes get the name "hypodermic" needles.
