Chapter 8: Hereditary & Environmental Interactions

Question 1

What is the interactionist approach?

Answer 1

The idea that hereditary and environmental factors interact to influence developmental change.

-eg. A baby’s genetic makeup determines its developmental potential, but reaching that potential is very much dependent on the environment in which the baby grows up.

Question 2

What is developmental change?

Answer 2

• It is continuous throughout our lifespan and has been described as a lifelong process of gains and losses.
• Individual development is continuous and follows predictable milestones, although the rate of change and timing of milestones vary between individuals.

Question 3

What is the human genome?

Answer 3

The full collection of our genes.

Question 4

What are genes/genetic inheritance?

Answer 4

• The basic unit of our genetic material.
• Includes biological characteristics one is born with.
• They carry out genetic information and instructions for biological functioning and hereditary characteristics.
• Half of our genes are from our biological mother and half from our biological father.

Question 5

What are some examples of genetic disorders?

Answer 5

• Down syndrome
• Fragile X syndrome
• Alzheimer’s disease

Question 6

What are genetic disorders?

Answer 6

Disorders that affect development and may contribute to one or more of the following: physical illness, mental illness, dementia, and mental retardation (impaired cognitive functions.)

Question 7

Elaborate on identical twin studies.

Answer 7

• Identical twins have all their genes in common, if they share a similar characteristic it is likely to be due to a genetic contribution.
• Problem with this assumption- likely to share the same environment with similar experiences- the same environmental factors impacting on the development of their characteristics.
• Look the same and more likely to be treated alike.

Question 8

Elaborate on non-identical twin studies.

Answer 8

• Share approx 50% of their genetic material w their twin, same amount as any set of brothers and sisters.
• Issue of sharing the same environment comes into play and is difficult to separate from genetic inheritance.

Question 9

Describe the case of the ‘Jim twins’

Answer 9

• Identical twins separated early in life, became important participants in the Minnesota Twins Study that highlighted genetic and environmental connections that underlie developmental change.
• Although reared apart, Jim Lewis and Jim Springer discovered amazing similarities in their lives.
• eg. As children, were both nail biters. As adults, both suffered from migraines, both married women named Linda, then remarried to women named Betty, both had the same job, and even smoked the same brand of cigarettes
• The study also found how identical twins raised together OR apart were far more similar on psychological tests than non identical twins and siblings raised in the same family.