CHAPTER 5 - Genetics and Evolution

DNA

The molecule that stores genetic information in the cells of organisms

DNA four bases

• Adenine

• Thymine

• Cytosine

• Guanine

Chromosomes

Thread-like structures found within the nucleus of cells that carry genetic information in the form of DNA and proteins.

Genes

A segment of DNA that controls the development of specific traits in an organism.

Alleles

Two forms of the same gene (Dominant and recessive)

homozygous

both dominant or both recessive

heterozygous

has one dominant and one recessive

Genotype

An organism's complete set of genes (ex: Pp pp PP)

Phenotype

The observable characteristics of an organism, including its physical traits, behavior, and metabolism.

Nature vs. nurture argument (why do humans like social groups?)

• Nature believes in ultimate causes are  influenced by genes, evolution, and adaptation

• Nurture believes in Proximal causes influenced by learning, experiences, and socialization

DNA Sequencing

The process of figuring out the specific order of nucleotide bases (adenine, thymine, cytosine, and guanine) in a DNA sequence.

Human Genome Project

An large-scale, international, multi billion-dollar project whose goal was to map and sequence the human genome.

Genetic engineering

A process that uses laboratory-based technologies to alter the DNA makeup of an organism.

Genetically modified organisms (GMOs)

A plant, animal, or microorganism that has had its genetic material (DNA) intentionally altered

Transgenic organisms

Living things that have had their DNA altered by adding genes from another species.

Knockout mice

A laboratory mouse, genetically engineered by inactivating or "knocking out" a specific gene—either by replacing it or disrupting it with an artificial piece of DNA— to study the gene's function and its impact on behavior, physiology, and disease.

Behavioral genetics

Aims to understand the extent to which genetic factors contribute to individual differences in behavior, temperament, and cognitive abilities. Often uses studies of twins.

Monozygotic twins (identical)

Twins conceived from a single  sperm and fertilized egg (zygote) that splits into two, resulting in two embryos with the same genetic material and nearly always the same sex

Dizygotic twins (fraternal)

• Twins conceived from a two separate sperm and two seperate eggs (ova).

Heritability

A measure of how well differences in people's genes account for differences in their traits.

Concordances

Probabilities that related people will develop neuropsychiatric disorders.

Darwin’s Theory of Natural Selection and Evolution

• Postulate 1. Variation within the population:

• Postulate 2. Over reproduction

• Postulate 3. Competition

• Postulate 4. Advantage

• Postulate 5. Modification through descent

Postulate 1. Variation within the population:

A population of interbreeding members shows variation in just about all aspects.

Postulate 2. Over reproduction

All organisms produce more offspring than can survive, yet populations stay relatively stable.

Postulate 3. Competition

Organisms compete for resources.

Postulate 4. Advantage

Nature selects those that survive and reproduce.

Postulate 5. Modification through descent

As the environment changes descendants change through generations.

Eugenics

Started with misrepresenting the theory of natural selection. The practice/advocacy of controlled selective breeding of human populations (as by sterilization) to improve the populations' genetic composition.

Positive eugenics

promoting reproduction in humans with “good” genes

negative eugenics

removal of “bad” genes for human populations

Which of the following is NOT one of the four bases of DNA?

1. Cytosine

2. Adenine

3. Guanine

4. Thymine

5. Acetylcholine

5. Acetylcholine

Which term best fits the description: “two forms of the same gene”?

1. Homozygous

2. Alleles

3. Phenotype

4. Nurture

2. Alleles

1. Proximal causes of behavior are those causes influenced by genes, evolution and adaptation.

   1. True

   2. False

2. False

Biofeedback can be used to do which of the following?

1. Control elements of the autonomic nervous system

2. Reduce effects of some psychiatric disorders

3. Lower heart rate and blood pressure

4. All of the above

5. None of the above

4. All of the above