BIO1020 EXAM 4

nonliving components or factors in an environment

abiotic factors

Determined by the numbers of individuals in a different age group

age structure

“self-feeders” synthesize the organic compounds of their bodies from inorganic precursors

autotroph

Any of the various chemical cycles, which involve both biotic and abiotic components of ecosystem

biogeochemical cycle

any concentration of a toxin, such as pesticides, in the tissues of tolerant species at increasingly higher levels in a food chain

biomagnification

a characteristic terrestrial ecosystem that occurs on at least two different continents

biome

 all of the ecosystems on the planet and determine how they interact with each other

biosphere

living components or factors in an environment

biotic factors

producers at bottom have a limiting affect on individual higher organisms above

bottom-up effects

A situation in which the abundance of organisms at each trophic level is limited by nutrient supply or the availability of food at lower trophic levels; thus, the supply of nutrients controls plant numbers, which control herbivore numbers, which in turn control predator number

bottom-up effects

An organism that consumes animals for nutrition

carnivore

the maximum/sustainable number of individuals that the environment can support

carrying capacity

energy from inorganic oxidation reactions (prokayotes)

chemoautotroph

group of interacting population that are usually found in a specific space 

community

community that is the last one standing; occurs after inhibition occurs

climax community

uneven distribution of resources; common in nature

clumped dispersion

occurs when predators and prey or herbivores and plants interact over time.

coevolutionary arms race

benefits one species and is neutral to the other

commensalism

interaction that occurs when individuals of different species both use a resource that limits the survival and reproduction of each species

competition

The concept that when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population.

competitive exclusion

populations of different species but the same general types 

community

microbes that break up dead matter

decomposer

quantitative way of studying a population

demography

breaks down population into convenient units ( classes, gender, sexual mature vs immature) 

demography

sensitive to population size and only affect large populations 

density-dependent growth

Factors that affect the population and depend on population size

density dependent

have the same effect on small population as they would on a median or large population 

density-independent growth

Rate of growth of a population at any instant is limited by something unrelated to the size of the population

Density-independent effects

animals that eat decaying matter

detritivore

allows organisms to make their way away from where their native environment may be 

Dispersal mechanisms

behavioral interactions, resource competition

uniform dispersion

A natural or human-caused event that changes a biological community and usually removes organisms from it.

disturbance

such as fires and storms, play a pivotal role in structuring many communities.

disturbance

the study of the interactions between an organism and its environment

ecology

comprised of the predicted communities that should live equilibrium based on predictable factors of the environment such as sunlight or precipitation levels 

ecosystem

A function performed by an ecosystem that directly or indirectly benefits humans

ecosystem services

Growth of a population in an ideal, unlimited environment, represented by a J-shaped curve when population size is plotted over time.

exponential growth model

early successional species introduce local changes in the habitat; happens second

facilitation

number of offspring produced in a standard time

Fecundity

an area of low oxygen that can kill fish and marine life near the bottom of the sea

Gulf Dead zone

An animal that mainly eats plants or algae

herbivore

cannot synthesize organic compounds from inorganic precursors 

heterotroph

In population models, the per capita rate at which an exponentially growing population increases in size at each instant in time.

intrinsic growth rate

two different species that are competing for a similar resources at the same time 

interspecific competition

In Intrinsic Growth Rate, if birth rate is greater than death rate

positive result 

Three Possibilities of an Intrinsic Rate of Increase

1. Positive value: greater than 0 (positive r)
2. 2.Negative value: less than 0 (negative r)
3. 3.Equal to 0 (r=0)

Populations that have a +rate of intrinsic population increase

growing

Populations that have a -rate of intrinsic population increase

shrinking

Populations that have a 0 rate of intrinsic population increase

stays the same 

In Intrinsic Growth Rate, if immigration is greater than immigration rate

positive result 

In an Exponential Population Growth Model, when e = i, and there are no limits on population growth then

dN = riN

the number of individuals in the population

N

the rate of change over time

dN/dt 

the intrinsic rate of natural increase for the population = innate capacity for growth

ri

If two species are competing for a limited resource, the species that uses the resource more efficiently will eventually eliminate the other locally

Principle of competitive exclusion

one organism consuming another

Predator-Prey Relationship

predator or another organism that keeps everything together 

keystone species

usually have adjusted a population to avoid density dependent factors from becoming too prevalent 

K-selection

show probability of survival and reproduction through a cohort’s life

life table

Complete life cycle of an organism

life history

An element that must be added for production to increase in a particular area.

limiting nutrient

Population growth that levels off as population size approaches carrying capacity

logistic growth model

when one has suitable habitats and there’s a gap of unsuitable habitats but the organisms are close to each other in order to enable gene flow 

metapopulations

benefits both species

mutualism

death rate in a standard time

mortality

the gross primary productivity (GPP) less the respiration of the primary producers

net primary productivity

the total of all the ways an organism uses the resources of its environment

niche

The basis for analyzing behavior as a compromise between feeding costs and feeding benefits.

optimal foraging

benefits one species at the expense of another organism; harms the other

parasitism

light as energy source

photoautotroph

Groups of organisms of the same species

population

an animal that naturally preys on others

predator

an animal that is caught and killed by another for food

prey

productivity of the primary producers

primary productivity

there was no community existing there before this process started 

primary succession

the representation of total living biomass or organic matter present at different trophic levels in an ecosystem

pyramid of biomass

shows graphically the population, or abundance, in terms of the number of individual organisms involved at each level in a food chain

pyramid of numbers

where one is likely to encounter organism that makes up the population 

range

most species have __ geographic range

limited

individuals do not interact strongly with one another; not common in nature

random dispersion

The proportional abundance of different species in a community

relative abundance

The division of environmental resources by coexisting species such that the niche of each species differs by one or more significant factors from the niches of all coexisting species

resource partitioning

the scientific study supporting the practice of ecological restoration

restoration ecology

those that produce a large number of offspring and contribute few resources to each individual offspring

r-selection

what happens when an existing community is disturbed and what comes after it 

Secondary succession

the scientific study supporting the practice of ecological restoration

species richness

Express some aspects of age distribution 

survivorship curve

the reflection of the number of individuals who are in a population

survivorship curve

An ecological relationship between organisms of two different species that live together in direct and intimate contact

symbiosis

early successional species are characterized by r-selected species tolerant of harsh conditions; happens first

tolerance

all species that are arriving at the start of succession 

tolerance

A situation in which the abundance of organisms at each trophic level is controlled by the abundance of consumers at higher trophic levels; thus, predators limit herbivores, and herbivores limit plants.

top-down effects

process by which effects exerted at one level flow to influence two or more levels

trophic cascade

which level an organism “feeds” at

trophic level

 

What is the difference between abiotic and biotic factors in ecology?

ABIOTIC

* Climatic: Temperature, sunlight, precipitation(rainfall or snowfall) 
* Geological: plants that are growing in a certain type of soil, specific type of pH or mineral in the soil
* Physical: very exposed area in terms of wind, aquatic environment( light penetration lessens as you go deeper), pressure, terrestrial organism( elevation) 

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BIOTIC( 3 THINGS)

* Competition for limited resources
* Predation: eat something or become eaten 
* Disease: pathogens that may cause individuals to become sick 

do abiotic and biotic factors interact

yes, for example, rock and soil provide resources for plants, and plants cycle the nutrients through so they can end up back in rock/soil

What is the Butterfly effect in ecology?

a small change at one place in a complex system can have large effects elsewhere

What evidence supports the butterfly effect

the Chornobyl accident, while it happened in Ukraine the effects of the high radiation can be seen worldwide.

Describe graphically the exponential and logistic population growth models.

EXPO:  describes a population with unlimited resources, which keeps growing bigger and faster over time ; represented by a J shaped line

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LOGIS: describes a population that has limited resources or other limits to growth, which grows more slowly as it gets larger ; represented by a sigmoid curve

describe formulaically the exponential and logistic population growth models

EXPO: dN = riN → As time increases, population size increase; in theory as time increases, population size increase

* N:number of individuals in the population
* dN/dt: the rate of change over time
* ri: innate capacity for growth

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LOGIS: *dN/dt* = *rN* (*K – N*)*/K →* N/K Ratio: If N is really large and K is really small then we’ll find that the effect will be bigger

* As N approaches K, the rate of population growth begins to slow
* If N = K the population growth rate is zero