It’s due to stem cells. The genes in dna turn on and off to give a cell a specific job, so stem cells can be “programmed” as any cell the body needs. (Muscle cell, skin cell, etc)
Answer:
Darwin's theory consisted of two main points; 1) diverse groups of animals evolve from one or a few common ancestors; 2) the mechanism by which this evolution takes place is natural selection. This SparkNote will first take a look at Origin of the Species, and then more closely examine Darwin's theories.
The answer should be Non banded grains
Portals of entry are the sites where micro-organisms can enter a host and reproduce, causing diseases or infections. There are various portals of entry in the human body. This can include the skin, our mucous membranes, and even our respiratory and gastrointestinal tracts. Portals of exit are where these micro-organisms leave and spread to other individuals. Portals of exit include coughing, sneezing, and some of our bodily fluids.
