Chapter 3: Our Genes and Our Environment

heterozygous pairs of alleles

alleles in the pair of chromosomes that are different.

homozygous pairs of alleles

alleles in the pair of chromosomes that are the same.

epigenesis

how genetic material is turned on and off in different contexts; epigenetic processes include DNA methylation and DNA acetylation.

Maroun's parents spoke French to him as a baby, and now that he is in middle school, he has an excellent French accent as a result. Which genotype-environment correlation is this an example of?

passive

telomeres

structures that cap the ends of chromosomes, shorten as cells divide, and are necessary for cell life.

sex-linked traits

traits that are determined by the X chromosome only.

methylation

a biochemical process that involves the transfer of one carbon atom and three hydrogen atoms in order to turn on and off the biological switches that produce biochemical reactions that regulate various bodily systems.

mutation

a change in a DNA segment.

genotype

a person's heredity as produced by genetic code.

genotype-environment interaction

acknowledges that different people may respond differently to the same environment.

In college, Maroun had already had sufficient experience with English, French, and Spanish, so he chose Mandarin to fulfill his language requirement. Which genotype-environment correlation is this an example of?

active

niche-picking

also referred to as active genotype-environment correlation where the child actively seeks an environment or position that is best suited to their talents and interests.

Kevin has fetal alcohol syndrome, likely a result of his mother drinking alcohol while pregnant. Kevin's syndrome represents which type of non-environmental influence on development?

congenital

Rosie has HIV, likely a result of transmission while being born vaginally. Rosie's HIV represents which type of non-environmental influence on development?

congenital

Jayden's speech has been delayed, likely as a result of impaired neurological development associated with lead paint that is chipping in his family's apartment. Jayden's delayed speech represents which type of non-environmental influence on development?

constitutional

Jessica's telomere length has been shortened by her consumption of sugar-sweetened beverages, and shorter telomeres are associated with a greater risk of later diseases. Jessica's shortened telomeres represent which type of non-environmental influence on development?

constitutional

passive genotype-environment correlations

correlation where children play a passive role in choosing the type of environment in which they find themselves.

active genotype-environment correlation

correlation where the child actively plays a role in choosing their environment; also referred to as "niche-picking".

evocative genotype-environment correlation

correlation where the child's genetic predisposition evokes a response from the environment.

DNA

double helix shaped molecule containing the genetic code that contributes to each individual's development.

trisomy 21 is better known as

down's syndrome

In middle school, Maroun's teachers suggested he be accepted into the Spanish club after noticing how strong his language skills in Spanish were (likely as a result of learning more than one language when he was a baby). Which genotype-environment correlation is this an example of?

evocative

Karim has Sickle Cell Disease. Karim's disease represents which type of non-environmental influence on development?

hereditary

Sam has green eyes. Sam's eye color represents which type of non-environmental influence on development?

hereditary

the scare-rowe hypothesis states that

heritability is higher in privileged economic conditions.

which gene-linked disease is caused by a dominant gene and is associated with problems in planning, memory, and movement, ultimately resulting in dementia?

huntington's disease

Marcus has inherited one recessive gene for sickle cell disease and one unaffected dominant gene. He does not have the disease but does experience some symptoms of it during certain conditions. This is an example of

incomplete dominance

Riley is a survivor of childhood cancer, which she likely developed as a result of a gene mutation. Riley's cancer represents which type of non-environmental influence on development?

innate

Tomas had childhood leukemia, likely a result of a gene mutation due to exposure to pesticides. Tomas' disease represents which type of non-environmental influence on development?

innate

which type of environment has the most influence as we grow older?

non-shared

phenotype

observable characteristics; do not always match our genetic code.

embryonic stem cell

obtained from a zygote.

adult stem cell

obtained from tissue (such as bone marrow).

genotype-environment correlation

occur when different genotype are exposed to different environment, are either passive or evocative.

hereditary

of or passed down by inheritance from an ancestor; transmitted from parent to child.

allele

one of the two members of the pair of chromosomes; carries the same genetic information as the other.

range of reaction

possible phenotypic behavioral outcomes for a genotype interact with different types of environments- and in what way the range of one genotype's behavior outcomes differs from the range of another.

epigenetic theory

proposes that over the course of one's development, interactions among genetic activity, neural activity, behavior, and environmental influences produce development.

in vitro fertilization

reproduction in which multiple eggs are fertilized by sperm outside of a woman's body and then only the most healthy are transferred back to her uterus for potential pregnancy.

incomplete dominance

situation where the symptoms of a recessive-linked trait or disease manifest themselves only under certain conditions.

sex chromosomes

the 23rd pair of chromosomes. the only ones that differ between male and female. females have two x's and males have one x and one y.

chromosomes

the 46 structures in our cells that contain genetic information.

polygenetic inheritance

the interaction and product of multiple genes in developing human characteristics such as eye color, weight, height, etc.

autosomes

the other 22 pairs of chromosomes (not the sex chromosomes); similar in males and females.

heritability

the portion of the differences among people that is. due to genes.

norm of reaction

the way an individual's normative or average reaction varies with the specific environment.

genes

units of DNA which direct the development of one or more traits.