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.
5 is b because it makes more sense
Answer:
C) It involves interactions between biotic and
abiotic factors.
Explanation:
Ecosystems need energy imput, need both consumers and producers, and can exist on land, lakes, rivers and oceans.
Answer:
To facilitate DNA replication
Explanation:
The chromosomes must condense as to allow for DNA to replicate within the nucleus
