DoD Annual TrainingAnswer Key

A Sharp Decline In A Population

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QUESTION 1

stable population

ANSWER

a species whose population size fluctuates slightly above and below its carrying capacity

QUESTION 2

irruptive population

ANSWER

surge then crash. commonly in short lived reproducing organisms such as algae

QUESTION 3

cyclic fluctuations

ANSWER

boom and bust cycles found in lynx's, lemmings

QUESTION 4

top down, predation

ANSWER

t__d___ population regulation through ____

QUESTION 5

bottom up

ANSWER

b___ u____ population regulation size of the predator and prey populations is controlled by the scarcity of one or more resources

QUESTION 6

population crash

ANSWER

a sharp decline that occurs due to an overshoot unless the species can switch to a new resource move to an area with more resources

QUESTION 7

population density

ANSWER

the number of individuals in a population found in a particular area or volume

QUESTION 8

predation, parasitism, infectious disease, competition for resources

ANSWER

density dependent population controls have a greater effect as the population's density increases

QUESTION 9

bubonic plague

ANSWER

a plague that occurred in Europe during the 14th century that killed 25 million people because of unsanitary conditions

QUESTION 10

ecological succession

ANSWER

types and numbers of species in biological communities and ecosystem change in response to changing environmental changes

QUESTION 11

secondary succession

ANSWER

increase the biodiversity of an ecosystem by increasing the species richness and interactions among species, increase the complexity of food webs and nutrient cycling

QUESTION 12

facilitation

ANSWER

one set of species makes an area suitable for species with different niche requirements, but less suitable for itself

QUESTION 13

inhabitation

ANSWER

some early species may hinder the establishment and growth of other species

QUESTION 14

tolerance

ANSWER

plants in earlier stages are unaffected by plants that came in during earlier stages because the later plants are not in direct competition with earlier plants for resources

QUESTION 15

traditional view

ANSWER

succession proceeds in an orderly sequence along an expected path until a certain stable type of climax community occupies an area

QUESTION 16

current view

ANSWER

ever changing mosaic of patches of vegetation, ongoing struggles by different species for enough light, water, nutrients, food

QUESTION 17

stability

ANSWER

capacity to withstand external stress and disturbance, maintained only by constant changes in response to environmental changes

QUESTION 18

inertia persistence

ANSWER

ability of a living system to survive moderate disturbances

QUESTION 19

resilience

ANSWER

ability of a living system to be restored through secondary succession after a moderate disturbance

QUESTION 20

clumping

ANSWER

when species tend to cluster where resources are available

QUESTION 21

coevolution

ANSWER

species evolve together

QUESTION 22

parasitism

ANSWER

occurs when one species (parasite) feeds on another organism (the host) that benefits while the host is harmed

QUESTION 23

commensalism

ANSWER

an interaction that benefits one species but has little effect on the other

QUESTION 24

mutualism

ANSWER

two species behave in ways that benefit both by providing each with food, shelter, or some other resource

QUESTION 25

gut inhabitant mutualism

ANSWER

bacteria in guts of organisms help to digest food and the organism provides a place for the organism to live and get food

QUESTION 26

population

ANSWER

group of interbreeding individuals of the same species

QUESTION 27

births, deaths, immigration, emigration

ANSWER

4 ways population size is governed by

QUESTION 28

age structure

ANSWER

main factor in how populations can grow, shrink, or remain stable

QUESTION 29

water, light, space, and nutrients

ANSWER

ways that the size of populations are controlled by limiting factors

QUESTION 30

range of tolerance

ANSWER

variations in physical and chemical environment. temperature, amount of sunlight

QUESTION 31

limiting factor principle

ANSWER

too much or too little of any physical or chemical factor can limit or prevent growth of a population. even if all other factors are at or near the optimal range of tolerance

QUESTION 32

environmental resistance

ANSWER

all factors that act to limit the growth of a population. largely determines an area's carrying capacity

QUESTION 33

carrying capacity

ANSWER

the maximum population a given habitat can sustain

QUESTION 34

exponential growth

ANSWER

a population that has few, if any, limitations on its resource supplies can grow exponentially at a fixed rate. it starts slowly then accelerates to carrying capacity when meets environmental resistance. J shaped curve

QUESTION 35

Logistic growth

ANSWER

a decreased population growth rate as population size reaches carrying capacity. s shaped curve

QUESTION 36

resource partitioning

ANSWER

adaptations that allow species to reduce or avoid competition with other species for resources, especially when the resource is limited or scarce

QUESTION 37

interspecific competition

ANSWER

two or more species interact to gain access to the same limited resources such as food, light, and space

QUESTION 38

predation

ANSWER

occurs when a member of one species competition for similar scarce resources evolve specialized traits that allow them to share resources

QUESTION 39

chemical warfare

ANSWER

when an organism ejects a noxious chemical spray as a way to avoid predators

QUESTION 40

mimicry

ANSWER

ex: a viceroy butterfly is not distasteful to predators, but it gains protection bc they look like the monarch which isn't wanted

QUESTION 41

warning colorations

ANSWER

warns predators that they are dangerous that helps to keep predators away

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