Chapter 8 Understanding Populations
An example of a population is
all maple trees in a forest
Which of the following statements is correct?
an organism's habitat is a location
A population's ______ is the number of its members or unit area or per volume
density
If a pair of mice finds a place to live with plenty of food and no predators, the population of mice will probably undergo ________ growth
exponential
Over a long period of time, two species can develop adaptations that increase the benefit of their relationship in the process of ______
coevolution
A robin that does not affect the tree in which it nests is an example of _______
commensalism
In which of the following relationships is neither species harmed?
commensalism
Deaths that are caused by a disease spreading through a population are ______ dependent
density
The number of wild horses per square kilometer in a prairie is the horse populations
density
A population's _____ is usually described as even, clumped, or random
dispersion
The average age at which members of a species reproduce is that species' _______
generation time
If two species use the same food source at different times, they are ___ competitors
indirect
Unlike a predator in relation to its prey, a parasite does not usually _______ its host
kill and eat
The amount of food available for wolves in an area determines the ecosystem's carrying capacity for wolves and is a ________ resource for wolves
limiting
A true statement about parasitism is that parasites
may cause their hosts to become more vulnerable to predators
The organisms in a cow's stomach have a constant source of food; the organisms help the cow break down and use the grass it eats. This type of relationship is an example of ______
mutualism
The relationship between acacia trees and the ants that live on them is an example of
mutualism
A population has a ______ growth rate when the death rate is higher than the birth rate
negative
A species' ______ includes that species' physical home, the environmental factors necessary for that species' survival, and all its interactions with other organisms
niche
Which of the following is one of the main properties used to describe a population?
number of individuals
A liver fluke is a _______ that harms its host as it obtains food
parasite
A ______ usually only weakens its host, while a _______ usually kills its prey
parasite, predator
The relationship between a Canadian lynx and a snowshoe is an example of
predator and prey
The type of interaction between cats and mice is ______
predator-prey
Which of the following is not an example of exponential growth?
reindeer of the Pribilof Islands after eating most of the lichens
If over a long period of time, each pair of adults in a population had only two offspring and the offspring lived to reproduce, the population would
remain the same
Which of the following has the greatest effect on reproductive potential?
reproducing earlier in life
The maximum number of offspring that each number of a population can produce is the population's ______
reproductive potential
Niche ______ is when each species uses less of the niche than it is capable of using, in order to reduce competition for resources with other species
restriction
The three main properties used to describe a population are _____, _______, and ________
size, density, dispersion
Which of the following populations has a random dispersion?
solitary snakes in a desert
The carrying capacity of an environment for a particular species at a particular time is determined by the
supply of most limited resources
A relationship in which two organisms live in close association, such as mutualism and commensalism, is called _____
symbiosis
Which of the following statements is not correct?
symbiosis is a relationship in which two organisms live apart
Members of a species compete indirectly for resources by competing for a ________ and for social dominance
territory
Which of the following reproductive situations will limit a population's biotic potential?
the maximum number of offspring each individual can produce
A female dog's niche includes all of the following except
the neighbor's enclosed yard
The density of a population is
the number if individuals per unit area
Which of the following statements explains why the growth of orchids on the high branches of tropical trees is an example of commensalism?
the trees are neither benefited nor harmed
The difference between a predator and a parasite is that a predator
usually kills and eats its prey
WHich of the following would most likely cause a large number of density-independent deaths in a population?
winter storms
A species of plant has exponential growth after it is introduced into an area where it has never lived. Which statement best describes exponential growth?
within few years the population increases dramatically
Each of the following is an example of a parasite except
a cow in a pasture
Which of the following organisms has the highest reproductive potential?
bacteria
Thick fur is not an example of coevolution. Why?
because thick fur evolved in response to a cold climate, not in response to other organisms
Competition for food cannot occur
between animals from two different ecosystems
A population's growth rate is its _____ rate minus its ______ rate
birth, death
The _________ of an ecosystem for a particular species is the maximum population that the ecosystem can support indefinitely
carrying capacity
A type of interaction between two species in which both species are harmed is ______
competition