Answer:
it keeps them alive and unseen by their enemies. keeps them from getting eaten
Red blood cells carry oxygen; white blood cells fight disease.
Invertebrates are what they can be classified as
There are 6 levels of organisational structure of the human body...
1. Chemical level
2.Cellular level
3. Tissue level
4. Organ level
5. System level
6. Organismal level
Highest level is organismal.
This is true, Darwin spent over 20 years developing his theory of natural selection
