Module 14 Reading Check

Which of the following must be males?

• dizygotic twins

• monozygotic twins

• Down syndrome children

• Klinefelter's syndrome children (XXY)

• Turner's syndrome children (XO)

If a class of 20 students is equally divided between boys and girls, in how many students would you find Y chromosomes?

• 5

• 15

• 10

• 20

• 0

Which of the following factors increases a person's likelihood of experiencing heart disease or diabetes?

• parents with heart disease or diabetes

• 47 chromosomes instead of 46

• no Y chromosome

• a sibling with the same genes

• There is no correlative/predictive factor

Fraternal twins develop when...

• one sperm fertilizes one egg.

• one sperm fertilizes two eggs.

• two sperm fertilize one egg.

• two sperm fertilize two eggs.

• three sperm fertilize two eggs.

Similar behaviors from identical twins who grew up in different homes provide evidence for the influence of...

• economic background.

• schooling.

• heredity.

• environment.

• nurture.

Genes are...

• identical in siblings who have the same parents.

• passed along from parent to child.

• not thought to influence a person's behavior.

• identical in dizygotic twins.

• similar in monozygotic twins.

Most researchers today believe that human behavior is determined by...

• nature.

• nurture.

• a combination of some nature, but mostly nurture.

• natural forces unlocked by nurturing forces.

• neither nature or nurture.

Explain how epigenetics may provide an explanation for why separated identical twins look different as they age.

Why are twin studies special in psychology? What unique insights can only these studies provide?