Example of selective breeding: Cows that produce lots of milk. Selective breeding to create more useful varieties of animals and plants is a form of biotechnology that human beings have used for thousands of years. Biotechnology includes any use of science or technology to alter the characteristics of a particular breed or animal.
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:
because of factories and cars and smoking
Explanation: