Biology 301 test South USC

Biology 301 test 3 April South USC

Terms in this set (...)

A genetic marker that consists of tandem repeats of non-protein-coding DNA sequences of 2, 3, or 4 nucleotides:
Ultimate source of all genetic variation:
A genetic marker that consists of DNA sequence variation occurring when a single nucleotide in the genome differs between members of a species:
Single Nucleotide Polymorphism (SNP)
Variation of any kind that has a genetic basis and is used to study population processes that influence patterns of genetic variation:
Genetic Markers
The genotype of mitochondrial and gametic portions of our genomes:
An American geneticist who stated in 1903 that if there was no selection, genotype frequencies remain constant from generation to generation:
William Castle
The mathematical proposition that the frequencies of alleles and genotypes remain unchanged from generation to generation in a population of infinite size in the absence of evolution (natural selection, mutation, genetic drift and assortative mating):
The occurrence of more than one distinct phenotype or genotype in a population:
A species that substantially affects the structure of communities, although species might not be particularly numerous:
Keystone Species
The distribution of organisms into specific zones according to various parameters such as altitude or depth:
A curve that plots the relative abundance of each species in a community in rank order from the most abundant species to the least abundant species:
Rank-Abundance Curve
Communities in which species do not depend on each other to exist:
This property of a rank-abundance curve has an inverse relationship with species evenness:
The number of species in a community:
Species Richness
The hypothesis that more species are present in a community that experiences occasional disturbances than in a community with either frequent or rare disturbances:
Intermediate Disturbance Hypothesis
A boundary created by sharp changes in environmental conditions over a relatively short distance, accompanied by a major change in the composition of species:
The most commonly observed relationship pattern noted across species between diversity and productivity:
The proportion of individuals in a community represented by each species:
Relative Abundance
This property of a rank-abundance curve has a direct relationship with species richness:
Run of the line along the X-axis
A comparison of the relative abundance of each species in a community:
Species Evenness
A normal, or bell-shaped, distribution that uses a logarithmic scale on the x-axis:
Log-Normal Distribution
An assemblage of species living together in a particular area:
Keystone species that affect communities by influencing the structure of a habitat:
Ecosystem Engineer
Communities in which species depend on each other to exist:
The most common type of endomycorrhizal fungi that infects a tremendous number of plants particularly apple trees, peach trees, coffee trees, and grasses:
Mutualist species that interact with one other species or a few closely related species:
Two species that provide fitness benefits to each other, but the interaction is not critical to the persistence of either species:
Facultative Mutualists
Fungi characterized by hyphal threads that extend far out into the soil and penetrate root cells between the cell wall and the cell membrane:
Endomycorrhizal Fungi
Mutualist species that interact with many other species:
Two species that provide fitness benefits to each other and require each other to persist:
Obligate Mutualists
Fungi characterized by hyphae that surround plant roots and enter between root cells but rarely enter the cells:
Ectomycorrhizal Fungi
Fungi that live inside a plant's tissue:
Endophytic Fungi
The final seral stage in the process of succession; generally composed of organisms that dominate in a given biome:
Climax Community
The development of communities in disturbed habitats that contain no plants but still contain organic soil such as plowed fields or forests uprooted by a hurricane:
Secondary Succession
A climax community that is not persistent; occurs when a site is frequently disturbed so a climax community cannot persist:
Transient Climax Communities
The earliest species to arrive at a site; typically are able to disperse long distances and arrive quickly at disturbed sites:
Pioneer Species
A mechanism in which one species increases the probability that a second species can become established:
A successional stage that persists as the final seral stage due to periodic fires:
Fire-Maintained Climax Community
Each stage of community change during succession:
Seral Stage
A mechanism in which one species decreases the probability that a second species will become established typically by competition, predation, or parasitism:
The time it takes after a disturbance for a community to return to its original state:
Community Resilience
The process by which the species composition of a community changes over time.
When the arrival of species at a site affects the colonization of other species; often occurs through inhibition:
Priority Effect
The amount a community changes when acted upon by a disturbance such as addition or removal of a species:
Community Resistance
A sequence of communities that exist over time at a given location:
A mechanism of succession in which the probability that a species can become established depends on its dispersal ability and its ability to persist under the physical conditions of the environment:
When a successional stage persists as the final seral stage due to intense grazing:
Grazer-Maintained Climax Community
The development of communities in habitats that are initially devoid of plants and organic soil, such as sand dunes, lava flows, and bare rock:
Primary Succession
Fungus and algae pair up to make these obligate muralist organisms:
Bacteria that assist legume plants:
This fish assists apheid shrimp with poor eyesight by warning of predators through fin flick and movement; in return the fish is allowed to live in the shrimp's burrow:
This fish cleans ectoparasites off larger fish:
This tree provides ants with homes in its thorns and nectar as food while the ants provide the tree with protection from various herbivores:
These benefits are provided to bacteria that have a mutualistic relationship with legume plants:
Root nodules (housing); Products of photosynthesis
These birds eat ticks found on grazing animals in Africa:
This species of plant requires a specific species of moth for pollination as the moth will lay its eggs within the flower and the moth larvae will eat some of the plant's seeds. The plant is able to selectively abort flowers that contain too many moth eggs so that it does not waste resources creating seeds that will only end up feeding larvae:
The Omphalocarpum procerum tree found in Africa has an extremely large fruit whose seeds will not germinate without passing through the gut of this animal:
This benefit is provided to legume plants that have a mutualistic relationship with bacteria:
Nitrogen Fixation
Termites house these within their gut as these organisms are able to break down wood particles that the termite may not otherwise be able to digest on its own:
Long, tubular flowers would have a mutualism with what animal as a pollinator?
The whitebark pine tree relies on this bird for dispersal of its offspring. The bird gathers seeds and hides them, but it hides so many that it does not ever eat them all therefore some are left to germinate:
This organism has a mutualism with other animals and acts as an indicator of beehive locations in order to receive the larvae and wax from the hive once other organisms have broken it open:
Greater Honeyguide
The most typical method of how plants attract dispersal agents:
Large flowers that tend to open at night would have a mutualism with animal as a pollinator?
A species that eats secondary consumers:
Tertiary Consumer
An indirect effect caused by changes in the traits of an intermediate species:
Trait-Mediated Indirect Effect
A linear representation of how different species in a community feed on each other:
Food Chain
A species that feeds at several trophic levels:
Indirect effects in a community that are initiated by a predator:
Trophic Cascade
A complex and realistic representation of how species feed on each other in a community:
Food Web
Within a given trophic level, a group of species that feeds on similar items; members of the group are not necessarily related:
When the abundances of trophic groups are determined by the amount of energy available from producers:
Bottom-Up Control
A level in a food chain or food web of an ecosystem:
Trophic Level
An interaction between two species that does not involve other species:
Direct Effect
When the abundances of trophic groups are determined by the existence of predators at the top of the food web:
Top-Down Control
A species that eats producers:
Primary Consumer
An interaction between two species that involves one or more intermediate species:
Indirect Effect
The ability of a community to maintain a particular structure:
Community Stability
A species that eats primary consumers:
Secondary Consumer
An indirect effect caused by changes in the density of an intermediate species:
Density-Mediated Indirect Effect