Harry Harlow was an American psychologist, who through his study proof that children need love and affection to develop normally. He demonstrated this by using rhesus monkey babies, who are taken away from their mothers immediately after birth. In place of their real mother, Harry provided two surrogate mothers instead and allow the monkey to chose any one they prefer. The first surrogate mother was made of wire and monkeys can get food from her while the second surrogate mother was made of soft terry cloth but the monkey can not get any food from her. Harry observed that the monkeys prefer to stay with their terry cloth mother, which provide comfort and security than with the one made of wire. The monkeys only go to the wire mother when they are hungry.
The polymerase chain reaction relies upon unusual, heat-resistant __DNA polymerase molecules______ that were isolated from bacteria living in hot springs.