Biology 30 Unit 8 Terms- Population and Community Dynamics

Population

Population

A group of individuals of the same species living in the same area.

Genes

Units of heredity that are passed from parents to offspring and determine traits.

Allele

Different forms of a gene that occupy the same position on homologous chromosomes.

Gene pool

The total collection of genes and their alleles in a population.

Genotype frequency

The proportion of individuals in a population that have a particular genotype.

Phenotype frequency

The proportion of individuals in a population that exhibit a particular phenotype.

Allele frequency

The proportion of a particular allele in a population's gene pool.

Hardy-Weinberg principle

States that the frequencies of alleles and genotypes in a population will remain constant from generation to generation in the absence of other influences.

Hardy-Weinberg equation

A mathematical equation used to calculate the frequencies of alleles and genotypes in a population. p+q=1

Genetic equilibrium

The state in which the frequencies of alleles and genotypes in a population remain constant over time.

Microevolution

Small-scale changes in allele frequencies within a population over generations.

Genetic diversity

The variety of different alleles and genotypes present in a population.

Mutation

A random change in the DNA sequence of a gene, which can introduce new alleles into a population.

Gene flow

The movement of genes from one population to another through migration or interbreeding.

Non-random mating

When individuals in a population choose mates based on specific traits, rather than mating randomly.

Genetic drift

Random changes in allele frequencies in a population due to chance events.

Founder effect

When a small group of individuals establishes a new population, leading to reduced genetic diversity.

Bottleneck effect

When a population undergoes a drastic reduction in size, leading to reduced genetic diversity.

Natural selection

The process by which individuals with advantageous traits are more likely to survive and reproduce, leading to changes in allele frequencies over time.

Homozygote advantage

When individuals with two copies of the same allele have a higher fitness than individuals with two different alleles.

Population density

The number of individuals of a species per unit area or volume.

Growth rate

The rate at which a population's size changes over time.

Per capita growth rate

The average rate of population growth per individual.

Biotic potential

The maximum rate at which a population can grow under ideal conditions.

Exponential growth pattern

A pattern of population growth in which the population size increases at an accelerating rate.

Carrying capacity

The maximum number of individuals of a species that an environment can support.

Density-dependent factors

Factors that influence population growth and are affected by the population's size and density.

Environmental resistance

The combination of all factors that limit population growth.

Density-independent factors

Factors that influence population growth regardless of the population's size and density.

r-selected strategies

Reproductive strategies that prioritize high population growth rates, often in unstable or unpredictable environments.

k-selected strategies

Reproductive strategies that prioritize the survival and reproduction of a few offspring, often in stable or predictable environments.

Intraspecific competition

Competition between individuals of the same species for limited resources.

Interspecific competition

Competition between individuals of different species for limited resources.

Predators

Organisms that hunt and kill other organisms for food.

Prey

Organisms that are hunted and killed by predators.

Protective collaboration

A type of interaction between species in which one species provides protection to another.

Symbiosis

A close and long-term interaction between different species.

Mutualism

A type of symbiotic relationship in which both species benefit.

Parasitism

A type of symbiotic relationship in which one species benefits at the expense of the other.

Succession

The process of change in the species composition of a community over time.

Primary succession

The colonization of an area that has not been previously inhabited by living organisms.

Pioneer community

The initial group of species that colonize a newly formed or disturbed habitat.

Climax community

The stable and mature community that develops after a series of successional changes.

Ecological disturbance

A discrete event that disrupts an ecosystem, such as a fire or a storm.

Secondary succession

The process of ecological succession that occurs after a disturbance in an existing ecosystem.

Sustainability

The ability to maintain ecological balance and meet the needs of the present generation without compromising the ability of future generations to meet their own needs.

Age pyramid

A graphical representation of the age distribution of a population, typically displayed as a pyramid-shaped graph.