Bio Chap 53/54 Homework

6 September 2022
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Which of the following is an example of a population?
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all of the redwood trees that live in a forest This includes the individuals of one species in one place that presumably interact, use the same resources, and are influenced by the same environmental conditions.
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To determine the density of a rabbit population, you would need to know the number of rabbits and _____. To
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the size of the area in which they live Density is the number of individuals of population per unit area
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In wild populations, individuals most often show a _____ pattern of dispersion.
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clumped individuals are often found clumped because they are interacting are attracted to areas that provide the most favorable environmental conditions
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Which of the following conditions favors "big-bang" reproduction?
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low rates of offspring survival if the probability of any one offspring surviving is low, then parental fitness is enhanced by maximizing the offspring production
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In the models that describe population growth, r stands for _____.
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R = per capita population growth rate the growth rate of a population is represented by r, which is equal to the per capita birth rate minus per capita death rate
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Which of the following statements are true of logistic growth?
Which of the following statements are true of logistic growth?
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b. As the population approaches carrying capacity, it grows more slowly. d. When the population reaches carrying capacity, it stops growing.
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Which of the following statements are true of a population at carrying capacity?
Which of the following statements are true of a population at carrying capacity?
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- The population growth rate equals zero -the rate at which resources are used is equal to the rate at which they are supplied -the birth rate equals the death rate
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as a population approaches carrying capacity, environmental resistance ______
as a population approaches carrying capacity, environmental resistance ______
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increases
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Which of the following factors does not contribute to environmental resistance? birth rate environmental toxins competition for food competition for space weather conditions
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birth rate
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Which processes increase a population's size?
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births and immigration Immigration is the movement of individuals into a population, so births and immigration increase a populations size
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True or false? Factors that determine the per capita rate of increase of a population include the age of breeding and the number of offspring produced each year.
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true - the per capita rate of increase of a population is the difference between the *per capita birth rate* and the *per capita death rate* , and is determined by factors that include the age of breeding and the number of offspring produced each year
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Which factor does not affect a habitat's carrying capacity? Availability of food. Maximum number of individuals in a population. Intensity of predation. Number of nesting sites.
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the maximum number of individuals in a population that can be sustained in a habitat over a period of time is the carrying capacity of a habitat
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Which equation represents the logistic growth rate of a population?
Which equation represents the logistic growth rate of a population?
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?N?t=rmaxN(K?N)K this equation represents the logistic growth rate of a population
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Which of the following statements about density-independent growth is true?
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Density-independent growth is also known as exponential growth.
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Under which of the following conditions would a population most likely experience exponential growth?
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young populations with few individuals meaning - young populations with few individuals are more likely to experience exponential growth because they have not used up the supply of resources
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Which of the following statements about a population experiencing logistic growth is true?
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If N is greater than K, the population will shrink This statement is true, since K is the maximum number of individuals that can be supported in a particular habitat over a sustained period of time.
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a populations carrying capacity
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may change as environmental conditions change def; carrying capacity - largest number of individuals of a population that a given environment can support
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Scientific study of the population cycles of the snowshoe hare and its predator, the lynx, has revealed that
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multiple biotic and abiotic factors contribute to the cycling of the hare and lynx populations.
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A human eats a deer. Which of these terms applies to the relationship between the human and the deer?
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predation The human is the predator and the deer is the prey.
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Humans and sharks both eat fish. Which of these terms applies to the relationship between the human and the shark?
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competition The human and the shark are both competing for a resource (fish).
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commensalism
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one member of the species pair benefits and the other is unaffected
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mutualism -
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both members of the species pair benefit,
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Humans who have pets tend to be healthier than humans who do not have pets. Which of these terms applies to the relationship between a human and a pet?
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In mutualism, both members of the species pair benefit; in this case the human is healthier and the pet is getting room and board.
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Which of these terms applies to the relationship between a dog and a blood-sucking tick?
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parasitism the tick benefits at the expense of the dog , the dog is the host and the tick is the parasite
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An egret eats insects stirred up by grazing animals. Which of these terms applies to the relationship between the egret and the grazing animal?
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commensalism In commensalism, one member of the species pair benefits and the other is unaffected; in this case the egret is getting a meal and the grazing animals are unaffected.
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According to the principle of competitive exclusion, two species cannot continue to occupy the same _____.
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ecological niche the competitive exclusion principal states that when populations of two 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 species
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Of the choices below, which best describes the effect predation has on the predator/prey organisms involved in the relationship?
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benefit... harmed the predator eats ( a benefit ) and the prey is eaten ( a harm )
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Cellulose-digesting microorganisms live in the guts of termites and ruminant mammals. The microorganisms have a home and food, and their hosts gain more nutrition from their meals. This relationship is an example of _____.
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mutualism
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In an ecosystem, phytoplankton are _____.
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producers - Autotrophs, such as phytoplankton, are producers.
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An earthworm that feeds on the remains of plants and animals is acting as a _____.
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detritivore the earthworm is feeding on the rains of dead organisms - detritivore
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When a human eats a steak, the human is acting as a _____.
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secondary consumer - by feeding on a primary consumer the human is acting as a secondary consumer
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A cow eating grass is an example of a _____.
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By feeding on a producer, the cow is acting as a primary consumer.
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A human who just ate a hamburger is eaten by a shark while swimming. The shark is acting as a _____.
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The shark that ate the human that ate the cow that ate the grass is the tertiary consumer.
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An organism's "trophic level" refers to _____.
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its food source meaning , an organisms trophic level is determined by what it eats
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Keystone species are those species _____.
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whose absence would cause major disruption in a community - a keystone species makes an unusually strong impact on community structure -A species that is not usually abundant in a community yet exerts strong control on community structure by the nature of its ecological role or niche.
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Caribbean coral reef communities have been strongly influenced by an unknown pathogen that causes white-band disease. How can the effect of white-band disease best be described?
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a cascade event that shifts the entire make up of the community the removal of the coral shifts the food supply within the reef, resulting in a completely different species composition
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The principle of competitive exclusion states that
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two species that have exactly the same niche cannot coexist in a community
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The feeding relationships among the species in a community determine the community's
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trophic structure