Derived from the inner cells of a human blastocysts , a very early human embryo.
At the blastocyst stage, five to 10 days after fertilization,
the embryo is a cluster of 100-200 cells
Answer:
option A
Explanation:
because plants give oxygen
False in order for an ecosystem to survive there has to be some sort of competition. for example, if there were no sharks to eat little fish the little fish would over populate and then the little fish would run out of food which then means that whatever the little fish ate is now extinct and so on hinting the food chain's name. If it wasn't for competition nothing would survive
