Answer:
the umbilical cord is considered both the physical and emotional attachment between mother and fetus.
Explanation:
this structure allows for the transfer of oxygen and nutrients from the maternal circulation into fetal circulation while simultaneously removing waste products from fetal circulation to be eliminated maternally.
There would be 40 units of energy left, because 10% is lost each time.
D.mutations
Im sure it cannot be anything else
The process by which forms of life having traits that betterenable them to adapt to specificenvironmental pressures, as predators, changes in climate, or competition for food or mates,will tend to survive andreproduce in greater numbersthan others of their kind, thusensuring the perpetuation of those favorable traits in succeeding generations.