Chapter 2 Life-Span Development

Question 1

Natural selection

Answer 1

an evolutionary process by which individuals of a species that are best adapted are the ones that survive and leave the most fit offspring

Question 2

Adaptive behavior

Answer 2

behavior that promotes an organism’s survival in the natural habitat, because an organism possess characteristics needed for survival

Question 3

Evolutionary Psychology

Answer 3

emphasizes the importance of adaptation and reproduction to ensure survival
- offspring that adapts, develops behaviors, and possesses self-productive traits to survive

Evolutionary developmental psychology: Interest has grown in using the concepts of evolutionary psychology to understand human development

Psychology mechanisms are domain-specific: ex: we developed sets of problem-solving skills for recurring problems like finding food

Question 4

Evolutionary Psychology: Connecting evolution and life-span development:

Answer 4

• The benefits conferred by evolutionary selection decrease with age
• Natural selection primarily operates during the first half of life and during reproductive viability
• Older adults weaken biologically and need culture-based resources such as cognitive skills, literacy, medical technology and social support.

Question 5

Evaluating Evolutionary Psychology

Answer 5

Criticisms:
- Does not adequately value social/environmental factors
- Relies on after-the-fact explanations
- Cannot be tested scientifically

Evolution does not dictate behavior

Evolution occurs on a time scale that does not lend itself to empirical study
- Thus the ideas coming out of evolutionary psychology are best tested by studying genes in humans and other species, and their links to traits and behaviors.

Question 6

The Collaborative Gene

Answer 6

Human life begins as a single cell

The nucleus of each cell contains chromosomes

Chromosomes: threadlike structures made up of deoxyribonucleic acid

DNA: a complex double-helix molecule that contains genetic code or info

Genes: a unit of hereditary information composed of DNA
- help cells to reproduce themselves
- manufacture the proteins that maintain life

Each gene has its own location-its designated place on a particular chromosome,
Today researchers strive to discover the specific locations of genes that are linked to certain functions and developmental outcomes

Question 7

Genetic expression is affected by their environment…

Answer 7

hormones in the blood can turn genes “on” or “off”

Certain genes are turned on or off as a result of exercise, mainly through methylation:
- Tiny molecules attach themselves to the outside of a gene, making the gene less capable of receiving and responding to biochemical signals from the body
- Stress, exercise, nutrition, radiation, temperature, and lack of sleep can negatively influence gene expression.

Question 8

Genes and Chromosomes

Answer 8

All of the cells in the body, except the sperm and egg, have 46 chromosomes in 23 pairs

Mitosis: the cellular reproduction in which the cell’s nucleus duplicates itself into two new cells

Meiosis: Cell division forming eggs and sperm (or gametes)

Fertilization: the reproductive stage when egg and sperm, fuse to form a zygote
- Zygote: a single cell, formed through fertilization, in which 23 unpaired chromosomes from the egg and 23 unpaired chromosomes from the sperm combine

Question 9

Genes and Chromosomes: Source of Variability

Answer 9

Combining the genes of two parents in offspring increases variability in the population.
- the chromosomes are brought together in the zygote in a unique combination
- in identical twins (monozygotic), a single zygote splits into two genetically identical replicas and becomes two individuals
- in fraternal twins (dizygotic), two eggs fertilized by different sperm create two nonidentical zygotes as genetically similar as ordinary siblings

Question 10

Mutated gene

Answer 10

a permanently altered segmented of DNA

Question 11

Susceptibility genes

Answer 11

genes that make the individual more vulnerable to specific diseases or accelerated aging

Question 12

longevity genes

Answer 12

genes that make the individual less vulnerable to certain diseases and more likely to live to an older age

Question 13

genotype

Answer 13

a person’s genetic material

Question 14

phenotype

Answer 14

how an individual’s genotype is expressed in observable and measurable physical psychological characteristics

expression is influenced by environmental factors.
- a genetic potential for height may be stunted by a lack of access to proper nutrition

Question 15

Sex-linked genes

Answer 15

When a mutated gene is carried on the X chromosome, the result is called X-linked inheritance

Most X-linked inherited diseases manifest in males, who have only one X chromosome.

Question 16

Dominant-recessive gene principle:

Answer 16

one gene of a pair always exerts its effects, overriding the potential influence of the other gene

Question 17

Genetic Imprinting

Answer 17

occurs when the expression of a gene has different effects depending on whether the gene is passed on by mother or father
- a chemical process prevents one member of the gene pair from expressing itself

imprinting is normal and can go awry, disturbing development and leading to growth disorders or cancer.

Question 18

polygenic inheritance

Answer 18

many different genes interacting, plus environmental influences, determine a characteristic or developing disease.

Question 19

gene-gene interaction

Answer 19

studies focusing on the interdependence of two or more genes in influencing characteristics, behavior, diseases, and development

Question 20

down syndrome

Answer 20

a form of intellectual disability caused by the presence of an extra copy of chromosome 21
- can cause intellectual and physical issues

chromosomal abnormalities known as sex-linked involve the presence of an extra X or Y chromosome or the absence of one X chromosome in females.

Question 21

Klinefelter syndrome

Answer 21

a sex-linked chromosomal disorder in which males have an extra X chromosome, making them XXY instead of XY

characteristics are underdeveloped testes, enlarged breasts and becoming tall

Question 22

fragile X syndrome (FXS)

Answer 22

a sex-linked disorder involving an abnormality in the X chromosome, which becomes constricted and often breaks
- can cause intellectual disability, learning disability, or short attention span

Question 23

turner syndrome

Answer 23

a sex-linked disorder in females in which either an X chromosome is missing or the second X chromosome is partially deleted
- can cause intellectual disability and sexual underdevelopment

Question 24

XYY Syndrome

Answer 24

a sex-linked disorder in which males have an extra Y chromosome
- can cause above-average height

Question 25

phenylketonuria (PKU)

Answer 25

a genetic disorder in which an individual cannot properly metabolize an amino acid called phenylalanine

Question 26

phenylketonuria (PKU)

Answer 26

a genetic disorder in which an individual cannot properly metabolize an amino acid called phenylalanine
- if left untreated, it results in intellectual disability and hyperactivity

Question 27

sickle-cell anemia

Answer 27

a genetic disorder that affects the red blood cells and occurs most often in people of African descent
- red blood cells become hook-shaped and cannot carry oxygen properly

Question 28

Dealing with genetic abnormalities

Answer 28

• each individual carried DNA variations that predispose the person to serious physical disease or mental disorder
• genes that are missing, nonfunctional, or mutated can contribute to disorders

identifying genetic flaws enables medical professions to
- predict an individual’s risk
- recommend healthy practices
- prescribe the safest and most effective drugs

Question 29

Prenatal Diagnostic Tests

Answer 29

a # of tests can indicate whether a fetus is developing normally

• ultrasound sonography
• brain-imaging techniques
• chorionic villus sampling
• amniocentesis
• material blood screening and cell-free DNA
• noninvasive prenatal diagnosis (NIPD)
• fetal sex determination

Question 30

infertility

Answer 30

the inability to conceive a child after 12 months of regular intercourse without contraception

Question 31

in vitro fertilization (IVF)

Answer 31

a process in which eggs and sperm are combined in a laboratory dish by experts
- one or more of the resulting by zygotes in transferred into the woman’s uterus
- multiple zygotes can increase health risks
- IVF success rate depends on the mother’s age and other factors

Question 32

adoption

Answer 32

is a social and legal process that establishes a parent-child relationship b/w persons unrelated at birth.

• U.S. couples are adopting a wide variety of children

Question 33

behavior genetics

Answer 33

the field that seeks to discover the influence of herdity and environment on individuals differences in human traits, development and behavior.

Question 34

twin study

Answer 34

the behavioral simililarity of identical twins is compared with the behavioral similarity of fraternal twins

Question 35

adoption study

Answer 35

seeks to discover whether behavioral and psychological characteristics or adopted children are more like those of their adoptive parents or biological parents

• adoptive parents provided the home environment
• biological parents contributed to their heredity.

Question 36

passive genotype-environment correlations

Answer 36

occur b/c biological parents provide a rearing environment for the child

Question 37

evocative genotype-environment correlations

Answer 37

occur b/c a child’s genetically-influenced characterisitcs elicit certain types of environments

Question 38

active (niche-picking) genotype-environment correlations

Answer 38

occur when children seek out environments that they find compatible and stimulating and suited for their genetically influenced abilities

Question 39

epigenetic view

Answer 39

development is the result of an ongoing, bidirectional interchange b/w heredity and environment

Question 40

gene x environment (G x E) interaction

Answer 40

the interaction of a specific measured variation in the DNA and a specific measured aspect of the environment
- the epigenetic mechanisms involve the actual molecular modification of the DNA strand as a result of environmental inputs in ways that alter gene functioning

Question 41

Conclusions about Heredity-Environment Interaction

Answer 41

• Genes produce proteins—or not— in many different environments throughout the life span
• complex behaviors are influenced by genes and environments in a way that gives people a propensity for a particular developmental trajectory
• we also can author a unique developmental path by changing the environment