Deck 2: A: Genetic Bases of Child Development

Question 1

The presence of a Y chromosome appears to be necessary for life.

Answer 1

False

Question 2

Genetic counsellors construct detailed family histories to determine the likelihood that someone is carrying an allele for a particular disorder.

Answer 2

True

Question 3

One problem with twin studies is that the experiences of identical twins may be more similar than the experiences of fraternal twins so that heredity appears to have a greater influence.

Answer 3

True

Question 4

If one identical twin is clinically depressed, the other twin has a 25 percent chance of becoming depressed.

Question 5

The presence of abnormal autosomes is a major cause for spontaneous abortions during the period of the zygote.

Question 6

About 80 percent of in vitro fertilization attempts succeed.

Question 7

Genes are made up of nucleotide bases.

Question 8

In adoption studies, if a behaviour has genetic roots, adopted children should behave more like their biological parents than their adoptive parents.

Question 9

About 50 percent of the differences in children's scores on intelligence tests are due to heredity.

Question 10

The risk of having a baby with Down syndrome decreases as the mother gets older.

Question 11

A homozygous individual has two alleles that are the same.

Question 12

If an allele for a disorder is dominant, then every person who receives the allele will have the disorder.

Question 13

Each sperm and egg contain 46 chromosomes.

Question 14

In twin studies, it is assumed that heredity influences a characteristic if fraternal twins are more alike than identical twins.

Question 15

In vitro fertilization involves combining the sperm and egg in a laboratory dish.

Question 16

Individuals with the sickle-cell allele are more resistant to malaria.

Question 17

Chromosomes consist of deoxyribonucleic acid (DNA).

Question 18

Most behavioural and psychological traits are polygenic traits.

Question 19

The autosomes determine the sex of the child.

Question 20

The extra 21st chromosome that is found with Down syndrome usually comes from the father's sperm.

Question 21

Heredity-environmental influences at any given point are affected by prior heredity-environmental exchanges.

Question 22

The same genotype for intelligence leads to the same phenotypes for intelligence. This is called reaction range.

Question 23

The traits controlled by single genes usually represent either-or phenotypes, while traits controlled by many genes typically represent an entire range of different outcomes.

Question 24

Although environmental factors are important, they usually affect each child in a unique way, which makes siblings differ.

Question 25

Heredity and environment interact dynamically throughout development.

Question 26

Experiences determine which phenotypes emerge, and genotypes influence the nature of experiences.

Question 27

The environment has no impact on when genes are activated-they follow a predictable and predetermined schedule based on maturation.

Question 28

The behavioural consequences of genetic instructions depend on the environment in which those interactions develop.