Chapter 2 Evolutions, Genetics, Experience Flashcards
True-breeding lines
Breeding lines in which interbred members always produce offspring with the same trait, generation after generation.
Zygote
The cell formed from the amalgamation of a sperm cell and an ovum.
Chromosomes
Threadlike structures in the cell nucleus that contain the genes; each chromosome is a DNA molecule.
Heritability estimate
A numerical estimate of the proportion of variability that occurred in a particular trait in a particular study and that resulted from the genetic variation among the subjects in that study.
- Heritability estimates range from zero to one. A heritability close to zero indicates that almost all of the variability in a trait among people is due to environmental factors, with very little influence from genetic differences
- A heritability close to one indicates that almost all of the variability in a trait comes from genetic differences, with very little contribution from environmental factors.
- Estimates of heritability use statistical analyses to help to identify the causes of differences between individuals. Example – cancer, smoking
Convergent Evolution
The evolution in unrelated species of similar solutions to the same environmental demands.
is the process whereby organisms not closely related (not monophyletic), independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.
ex bat wings and human arm
Enhancers
Stretches of DNA that control the rate of expression of target genes.
Homozygous
Possessing two identical genes for a particular trait.
Hominini
The family of primates that includes at least six genera: Australopithecus, Paranthropus, Sahelanthropus, Orrorin, Pan, and Homo.
Epigenetics
The study of all mechanisms of inheritance other than the genetic code and its expression.
Genotype
The traits that an organism can pass on to its offspring through its genetic material.
Ethology
The study of the behavior of animals in their natural environments.
Nucleotide Bases
A class of chemical substances that includes adenine, thymine, guanine, and cytosine—constituents of DNA.
Heterozygous
Possessing two different genes for a particular trait.
Genetic Recombination
The meiotic process by which pairs of chromosomes cross over one another at random points, break apart, and exchange genes.
Evolve
To undergo gradual orderly change
Phenylketonuria (PKU)
A neurological disorder whose symptoms are vomiting, seizures, hyperactivity, hyperirritability, intellectual disability, brain damage, and high levels of phenylpyruvic acid in the urine.
Ribonucleic acid (RNA)
A molecule that is similar to DNA except that it has the nucleotide base uracil and a phosphate and ribose backbone.
Transfer RNA
Molecules of RNA that carry amino acids to ribosomes during protein synthesis; each kind of amino acid is carried by a different kind of transfer RNA molecule.
Sex-linked traits
Traits that are influenced by genes on the sex chromosomes.
Amphibians
Species that must live in water during their larval phase; adult amphibians can survive on land.
Monozygotic twins
Twins that develop from the same zygote and are thus genetically identical.
Proteins
Long chains of amino acids.
Autosomal chromosomes
Chromosomes that come in matched pairs; in mammals, all of the chromosomes except the sex chromosomes are autosomal.
Polygyny
A pattern of mate bonding in which one male bonds with more than one female; the most prevalent pattern of mate bonding in mammals.
Human proteome
A map of the entire set of proteins encoded for by human genes.
Ontogeny
The development of individuals over their life span.
Exaptation
A characteristic that evolved because it performed one function but was later co-opted to perform another.
Transgenerational epigenetics
A subfield of epigenetics that examines the transmission of experiences via epigenetic mechanisms across generations.
Amino Acids
The building blocks of proteins.
Brain Stem
The part of the brain on which the cerebral hemispheres rest; in general, it regulates reflex activities that are critical for survival (e.g., heart rate and respiration).
Monogamy
A pattern of mate bonding in which one male and one female form an enduring bond.
Fitness
According to Darwin, the ability of an organism to survive and contribute its genes to the next generation.
Analogous
Having a similar structure because of convergent evolution (e.g., a bird’s wing and a bee’s wing are analogous).
Replication
The process by which the DNA molecule duplicates itself.
Homologous
Having a similar structure because of a common evolutionary origin (e.g., a human’s arm and a bird’s wing are homologous).
Dominant Trait
The trait of a dichotomous pair that is expressed in the phenotypes of heterozygous individuals.
Gametes
Egg cells and sperm cells.
Mutations
Accidental alterations in individual genes.
Alleles
The two genes that control the same trait.
Mitosis
The process of cell division that produces cells with the same number of chromosomes as the parent cell.
Species
A group of organisms that is reproductively isolated from other organisms; the members of one species cannot produce fertile offspring by mating with members of other species.
Phylogeny
The evolutionary development of species.
Histone Remodeling
An epigenetic mechanism wherein histones change their shape and in so doing influence the shape of the adjacent DNA. This can either increase or decrease gene expression.
Dichotomous traits
Traits that occur in one form or the other, never in combination.
Vertebrates
Chordates that possess spinal bones.
Nature-Nurture Issue
The debate about the relative contributions of nature (genes) and nurture (experience) to the behavioral capacities of individuals.
Mammals
A class of animals whose young are fed from mammary glands.
Spandrels
Incidental nonadaptive evolutionary by-products of some adaptive characteristic.
Natural Selection
The idea that those heritable traits that are associated with high rates of survival and reproduction are the most likely to be passed on to future generations.
Chordates
Animals with dorsal nerve cords.
Messenger RNA
A strand of RNA that is transcribed from DNA and then moves out of the cell nucleus where it is translated into a protein.
Transcription Factors
Intracellular proteins that bind to DNA and influence the operation of particular genes.
Polyandry
A pattern of mate bonding in which one female bonds with more than one male.
Histone
A protein around which DNA is coiled.
Meiosis
The process of cell division that produces cells (e.g., egg cells and sperm cells) with half the chromosomes of the parent cell.
Convolutions
Folds on the surface of the cerebral hemispheres.
Primates
One of 20 different orders of mammals; there are about a 16 families of primates.
Cerebrum
The portion of the brain that sits above the brain stem; in general, it plays a role in complex adaptive processes (e.g., learning, perception, and motivation).
Asomatognosia
A deficiency in the awareness of parts of one’s own body that is typically produced by damage to the right parietal lobe.
Phenylpyruvic acid
A substance that is found in abnormally high concentrations in the urine of those suffering from phenylketonuria.
Gene Expression
The production of the protein specified by a particular gene.
Zeitgeist
The general intellectual climate of a culture.
Phenotype
An organism’s observable traits.
Instinctive behaviors
Behaviors that occur in all like members of a species, even when there seems to have been no opportunity for them to have been learned.
Sex Chromosomes
The pair of chromosomes that determine an individual’s genetic sex: XX for a female and XY for a male.
Deoxyribonucleic acid (DNA)
The double-stranded, coiled molecule of genetic material.
RNA Editing
An epigenetic mechanism wherein messenger RNA is modified through the actions of small RNA molecules and other proteins.
Dizygotic twins
Twins that develop from two zygotes and thus tend to be as genetically similar as any pair of siblings.
Sensorimotor phase
The second of the two phases of birdsong development, during which juvenile birds progress from subsongs to adult songs.
Gene
A unit of inheritance; for example, the section of a chromosome that controls the synthesis of one protein.
Human Genome Project
The international research effort to construct a detailed map of the human chromosomes.
Cartesian dualism
The philosophical position of René Descartes, who argued that the universe is composed of two elements: physical matter and the human mind
Sensory phase
The first of the two phases of birdsong development, during which young birds do not sing but form memories of the adult songs they hear.
Ribosomes
A structure in the cell’s cytoplasm that translates strands of messenger RNA into proteins.
Conspecifics
Members of the same species.
Sensitive period
An interval of time during development when an experience can have a great effect on development if it occurs during that interval, and a weaker effect on development if it occurs outside that interval.
Recessive trait
The trait of a dichotomous pair that is not expressed in the phenotype of heterozygous individuals.
Codon
A group of three consecutive nucleotide bases on a DNA or messenger RNA strand; each codon specifies the particular amino acid that is to be added to an amino acid chain during protein synthesis.
DNA methylation
An epigenetic mechanism wherein a methyl group attaches to a DNA molecule, usually at cytosine sites in mammals. DNA methylation can either decrease or increase gene expression.
