Ch 3

What is the term for the entire set of genetic instructions for building a human being?

The genome

What specific molecules make up the genome?

DNA (deoxyribonucleic acid)

How are DNA chains organized within the human genome?

Into 46 chromosomes

How many chromosomes does a human receive from each parent?

23

What are specific areas on a strand of DNA that carry coded instructions for particular traits or functions called?

Genes

Under what condition will the feature of a dominant gene appear?

It will appear every time the gene is present.

A recessive gene's feature only appears if it is paired with what?

Another recessive gene for that same trait

What does it mean for a human characteristic to be polygenetic?

The trait is controlled by many genes working together rather than a single gene.

Name two examples of human traits that are typically polygenetic.

Height and personality

How can prenatal stress, poor health, or poor nutrition affect a fetus's birth weight?

They can lead to low birth weight.

What are two potential long-term issues for a fetus exposed to poor maternal nutrition or stress?

Long-term health or behavioral issues

Harmful external substances that can cause birth defects, developmental delays, or behavioral problems.

What are teratogens?

Give three examples of teratogens.

Viruses, drugs, and alcohol

What specific behavioral and developmental problem is associated with prenatal alcohol exposure?

Fetal Alcohol Syndrome

Why are early postnatal experiences considered crucial for brain development?

They physically shape the brain's architecture.

What is the neurological effect of positive stimulation during early development?

It helps form neural connections.

How does early childhood neglect impact the physical structure of the brain?

It can lead to a lack of development in certain brain regions.

A lack of normal nutrition, comfort, or stimulation during development.

What is deprivation in the context of development?

What is a likely long-term developmental consequence of severe deprivation?

Permanent developmental delays

• (providing a stimulating and emotionally supportive environment) can lead to improved cognitive and social outcomes

What is enrichment in developmental terms?

How does enrichment during development typically affect cognitive and social outcomes?

It leads to improved cognitive and social outcomes.

Which field of study examines how chemical 'tags' on DNA turn genes on or off?

Epigenetics

In epigenetics, what acts as a 'switch' to determine which genetic instructions are followed?

Chemical tags on the DNA.

How does epigenetics allow the body to respond to environmental changes?

By altering gene expression without changing the genetic code.

What are histones?

Proteins around which DNA is tightly wrapped.

How does the tightening of DNA packaging around histones affect gene access?

It makes certain genes inaccessible to be 'read' by the cell.

What occurs when epigenetic changes cause DNA packaging to loosen?

Specific genes become accessible for the cell to read.

What is the difference between the genetic code and gene expression in epigenetics?

The genetic code is the static blueprint, while gene expression is which parts of the blueprint are actually used.

Name two environmental factors that can prompt changes to the human epigenome.

Diet and stress (or exposure to toxins)

How does normal maturation (aging) affect an individual's epigenetics?

It prompts changes to the epigenome over time.

In the context of the nature vs. nurture debate, what role do genes (nature) play?

They provide the potential for development.

What determines how an individual's genetic potential is actually expressed throughout life?

The environment (nurture) and epigenetic factors.

Why is it considered illogical to ask if nature or nurture is more important?

Because the two forces are inseparable in human development.

What can a diet high in processed foods add to one's DNA?

Chemical tags (epigenetic markers)

How might a high-stress neighborhood in childhood affect an adult's biological stress management?

By triggering epigenetic changes that influence how the body manages stress.

What are genes?

Specific areas on a strand of DNA.

True or False: Epigenetics changes the underlying DNA sequence.

False

What constitutes the 'blueprint' of a human being in the epigenetic metaphor?

The genetic code.

What constitutes the 'operation' of the human body in the epigenetic metaphor?

Gene expression.

How many total chromosomes form the organization of a human DNA chain?

46

What is the primary physical outcome of a recessive gene if no dominant gene is present?

The recessive feature will appear.

What is the result of many genes working together to influence a single trait like height?

Polygenetic inheritance.

Which prenatal factor is specifically linked to premature birth and low birth weight?

Stress, poor health, or poor nutrition.

What are external substances that harm the fetus categorized as?

Teratogens.

How does deprivation differ from enrichment in developmental outcomes?

Deprivation leads to delays, while enrichment leads to improved cognitive and social outcomes.

What physically forms neural connections in the brain early in life?

Positive stimulation.

What does epigenetic 'packaging' refer to?

The way DNA is wrapped around histone proteins.

What can exposure to toxins change in the body?

The epigenome.

How many chromosomes are inherited from the biological father?

23.

How many chromosomes are inherited from the biological mother?

23.

What kind of gene's feature appears every time it is present?

A dominant gene.

If a child has a recessive trait, what must be true about their genes for that trait?

They must have two recessive genes for that trait.

Which environmental factor specifically involves a lack of comfort and stimulation?

Deprivation.

What is the relationship between DNA and the genome?

The genome is the entire set of genetic instructions made of DNA chains.

What determines which genetic instructions are 'read' by a cell?

The accessibility of DNA based on histone packaging and chemical tags.

What is the genetic code?

The sequence of DNA that acts as a blueprint but does not change due to epigenetic factors.

Name one physical effect a teratogen can have on a developing fetus.

Birth defects (or developmental delays).

How does enrichment affect social outcomes in children?

It leads to improved social development.

Early neglect can lead to a lack of development in specific what?

Brain regions.

In epigenetics, chemical tags act as what for genes?

Switches.

Which factor provides the potential for human development?

Nature (Genetics).

Which factors determine how developmental potential is expressed?

Nurture (Environment) and Epigenetics.

What is the primary function of chemical tags in the epigenome?

To turn genes on or off without changing the DNA sequence.

Can diet influence how genes are expressed later in life?

Yes, through epigenetic changes.

What defines the postnatal environment's role in brain development?

Early experiences physically shape the brain's architecture.

Poor prenatal health can lead to what kind of birth?

Premature.

Which trait is an example of a polygenetic characteristic related to the mind?

Personality.

Which trait is an example of a polygenetic characteristic related to physical stature?

Height.

What happens to a gene when its DNA packaging is loosened around histones?

It becomes accessible for gene expression.

What happens to a gene when its DNA packaging is tightened around histones?

It becomes inaccessible (turned off).

What is the full name of the molecule DNA?

Deoxyribonucleic acid.

How do aging and environmental factors interact with the genome?

They prompt epigenetic changes to the epigenome over time.

Fetal Alcohol Syndrome is caused by which specific type of prenatal factor?

Teratogens (specifically alcohol).

What provides the coded instructions for traits within a DNA strand?

Genes.