unit II Flashcards
What is behavior genetics?
A field of study that examines the role of genetic and environmental factors in shaping behavior, cognition, and personality.
What is the nature of behavior genetics?
It focuses on the interaction between genes and the environment, how heritability affects behavioral traits, genetic expression, and epigenetics.
What is gene-environment interaction?
The concept that both genetic predispositions and environmental factors influence behavior. Genetics can be enhanced or suppressed by environmental experiences.
Example of gene-environment interaction study?
Caspi et al. (2003) study on depression, showing that individuals with a specific serotonin transporter gene variant (5-HTTLPR) were more prone to depression when exposed to stressful life events.
What is heritability?
The proportion of variance in a trait within a population that can be attributed to genetic factors, expressed as a percentage.
Example of heritability study?
Twin studies by Bouchard et al. (1990) found that intelligence (IQ) heritability is about 50-80%, indicating a significant genetic component while also acknowledging environmental influence.
What is epigenetics?
The study of changes in gene expression that do not involve changes to the DNA sequence but are influenced by environmental factors.
What is Turner syndrome?
A chromosomal disorder where a female is born with only one X chromosome (monosomy). It affects development and leads to symptoms like short stature, heart defects, and infertility.
What is the inheritance pattern of PKU?
PKU follows an autosomal recessive inheritance pattern.
Example of epigenetics study?
Michael Meaney’s rat studies (2004) showed that maternal care (licking and grooming) affected the stress responses in offspring by altering gene expression, leading to calmer adult behavior.
What are chromosomes?
Structures made of DNA that carry genetic information. Humans have 23 pairs, including 22 pairs of autosomes and 1 pair of sex chromosomes.
What are autosomes?
Chromosomes that control the inheritance of traits, excluding those related to sex. Humans have 22 pairs of autosomes.
What is phenylketonuria (PKU)?
A metabolic disorder caused by a deficiency of the enzyme phenylalanine hydroxylase, leading to a buildup of phenylalanine, causing intellectual disability if untreated.
How is Turner syndrome diagnosed and treated?
Diagnosed using a karyotype test. Treatments include growth hormone therapy, estrogen replacement, and reproductive technologies.
What are sex chromosomes?
Chromosomes that determine an individual’s sex (X and Y chromosomes). Females typically have two X chromosomes, while males have one X and one Y chromosome.
What are the types of chromosomal mutations?
Nondisjunction: Failure of chromosomes to separate properly during cell division.
Trisomy: Presence of an extra chromosome.
Monosomy: Missing one chromosome.
Translocation: Part of a chromosome breaks and attaches to another.
What is Down syndrome?
A genetic disorder caused by trisomy 21, where an individual has an extra copy of chromosome 21. It results in developmental delays and physical features like a flat facial profile.
What are the types of Down syndrome?
Nondisjunction: Most common type.
Translocation: Part of chromosome 21 attaches to another chromosome.
Mosaic Down syndrome: Some cells have an extra chromosome 21, while others do not.
What is the function of neurons?
Neurons are the basic signaling units of the nervous system, transmitting information through electrical and chemical signals.
What are glial cells?
Cells that provide support, protection, and nutrition to neurons, and regulate the neural environment. Types include astrocytes, oligodendrocytes, and microglial cells.
What is the role of astrocytes in the brain?
Astrocytes regulate ion transport, provide structural support to neurons, and maintain the blood-brain barrier.
What is the blood-brain barrier?
A selective barrier that protects the brain from harmful substances in the bloodstream, maintained by astrocytes.
