Humans evolved 3 billion years ago after the earth was formed.<span />
Explanation:
In the majority of cases, the extra copy of chromosome 21 comes from the mother in the egg.
In a small percentage (less than 5%) of cases, the extra copy of chromosome 21 comes from the father through the sperm.
In the remaining cases, the error occurs after fertilization, as the embryo grows.
Willie on the bus with his classmates. Who is most likely to be diagnosed with psychopathology based on the criteria that his or her behavior impairs good daily functioning?
Elizabeth, who must walk up and down the bus steps 10 times before getting on
Answer: 5
Explanation:
Since 1 out of 200 people carry the defective gene that causes inherited colon cancer.
In a sample of 1000 individuals, we say
1 = 200
y = 1000
cross multiply
y x 200 = 1000 x 1
200y = 1000
y = 1000/200
y = 5
Thus, in a sample of 1000 individuals, approximately 5 will be carriers
