chapter 9 glossary Flashcards
Gene pool
the complete set of alleles present within a particular population
all alleles at all loci in a particular population (a particular habitat)
Gene
a selection of DNA that carries the code to make protein
Population
a group of individuals of the same species living in the same location `
Allele frequency
the proportion of certain alleles in gene pool
Genotype
the genetic composition of an organism at a particular gene locus
Phenotype
the physical or biochemical characteristics of an organism that are the result of the gene expression and the environment
Genetic diversity
the variation in genetic makeup or alleles within a population
Mutation
a change to a DNA sequence
Mutagen
an agent that can cause mutations in DNA
Deleterious mutation
a change in DNA that negatively effects an individual
Germline
a cell involved in the generation of gametes in eukaryotes
Somatic cell
any cell in an organism that is not a germline cell
Point mutation
a mutation that alters a single nucleotide in a DNA sequence
Block mutation
a mutation that effects a large chunk of DNA, or an entire gene
Silent mutation
a mutation in which a nucleotide is substituted for another, changing the codon, but still coding for the same amino acid. therefore there is no effect of the protein structure
Missense mutation
a mutation in which a nucleotide is substituted for another, changing the codon and coding for a different amino acid. therefore, there can potentially be an effect on protein structure
Nonsense mutation
a mutation in which a nucleotide is substituted for another, changing the codon to a stop codon, prematurely ceasing translation of the gene’s mRNA therefore, there is an effect on protein structure
Frameshift mutation
a mutation that involves the insertion or deletion of one or two nucleotides, altering every codon from that point forward
Degenerate
a property of the genetic code which means that a
Reading frame
the order in which nucleotide triplets or codons are divided into a consecutive, non-overlapping sequence
Environmental selection pressure
a factor in the environment that impacts an organisms ability to survive and reproduce
Competition
interactions between organisms in which both are negatively impacted when vying for the same limited resource. can exist within or between species
Natural selection
a mechanism through which organisms are better adapted to their environment have an increased chance of surviving and passing on their alleles
Biological fitness
the specimen’s ability to reproduce and generate viable offspring. Essentially, the fitness of the individual is based on its ability to pass genetic information on to the next generation, as opposed to any physical characteristic or trait.
Selective advantage
an organism conferred a beneficial allele, which increases its chances of survival against a specific environmental selection pressure
Evolution
the change in the genetic makeup of a population over successive generations
Genetic Drift
a dramatic event that dramatically alters a population’s gene pool
chance events that create an unpredictable change in alleles frequencies from generation to generation in small populations
- bottleneck effect
- founder effect
Bottleneck effect
the reduction in genetic diversity that occurs when a large proportion of the population is removed due to a chance event
the size of a population id severely reduced (ie.flood famine) and the few survivors are, by chance, unrepresentative of the original population, dramatically changing the allele frequencies and limiting the genetic diversity.
Founder effect
the reduction in genetic diversity that occurs when a population in derived from a small unrepresentative sample sample of the original population.
rare alleles occur in high frequency in population isolated from the general population as a result of a small sample of founding individuals who were, by chance, not represented in the original population.
Unrepresentative sample
a small selection of individuals from a larger group that does not reflect the characteristics of the larger group
Inbreeding
sexual reproduction of two related individuals
Adaptive potential
the ability fir a population to adjust to new environmental selection pressures
Interbreeding
when two individuals living in different populations mate and have offspring
Immigration
the movement into a population
Emigration
the movement of a population
Gene flow
the flow of alleles in and out of a population due to the migration or interbreeding individuals between two populations
Species
a group of individuals who are able to breed with each other and produce viable fertile offspring
Allopatric speciation
the geographic separation of a population from a parent population resulting in the formation of a new species
Sympatric speciation
the divergence of a species from an original species without the presence of a geographical barrier
Viable
able to survive
Fertile
the ability to produce an offspring
Geographical barrier
a physical factor that prevents gene flow, and thereby stops two population
Polyploidy
when an organism contains additional sets of chromosomes in its genome
Aneuploidy
Having missing or extra chromosomes
Selective breeding
the changing of a populations gene pool due to humans altering breeding behaviour of animals and plants to develop a selected trait , also known as artificial selection
Artificial selection
selective breeding , the changing of a population’s gene pool due to humans humans altering the breeding behaviour of animals and plants to develop a selected trait
Antimicrobial agent
an agent that kills or slows the growth of microorganisms. includes antiseptics, disinfectants, disinfectants, antifungals, antivirals, and antibacterials
Antimicrobial resistance
the ability of a microorganism to survive exposure to an antimicrobial agent
Bacterial conjugation
the process in which bacteria exchange genetic material by direct cell-cell contact
Virulence
the potential of a pathogen or disease to cause serious illness or harm
Antigenic drift
small and gradual mutations in the genes encoding for viral surface antigens
Antigenic shift
sudden and significant mutations in the genes encoding for viral surface antigens.
Viral recombination
the combination of surface antigens from two or more different strains of a virus to form a completely new virus subtype
Epidemic
a dramatically increased occurrence of a disease in a particular community at a particular time
Pandemic
an epidemic that has spread across multiple countries and/or continents
