Biology 152 Exam 5 Questions and Answers (Graded
A)
/Ecology - Answer-The study of interactions among organisms and their environment
/.Key population features - Answer-Distribution, growth, and size/density
/.Random distribution - Answer-When individuals in a population have an equal
probability of occurring anywhere, with no pattern. Ex: dandelions
/.Random distribution causes - Answer-Caused by neutral interactions between
individuals and the local environment
/.Uniform Distribution - Answer-Individuals are evenly spaced throughout the
environment. Ex: penguins
/.Uniform Distribution causes - Answer-Caused by antagonistic interactions between
individuals OR the local depletion of resources
/.Clumped distribution - Answer-Individuals live in areas of high local abundance
separated by areas of low abundance. Most common type. Ex: elephants or other herd
animals
/.Clumped distribution causes - Answer-Caused by attraction between individuals OR
attraction of individuals to a common resource
/.Allelopathy - Answer-Production of secondary compounds by plants that prevent
growth of other organisms around them, often seen in uniform distribution
/.Factors affecting population size - Answer-Births and immigration add, deaths and
emigration subtract
/.delta-N = N2 - N1 = (B - D) + (I - E) - Answer-The formula for population size change
/.r = (delta-N/delta-t)/N1 - Answer-Growth per Capita (intrinsic rate of growth) Formula
/.Nt = N1(1 + r)^t - Answer-Formula for the Size of a Population after a Set amount of
Time
/.Exponential growth - Answer-A pattern of data that shows greater increases with
passing time, creating a j-shaped curve
/.Delta-N/Delta-t = rN - Answer-the Exponential Growth Formula
, /.Exponential Curve - Answer-
/.Things that slow population growth - Answer-Diseases, competition over resources,
resource limitation, and predation. These are affected by population size.
/.Logistic growth - Answer-Population growth that is controlled by limited resources,
plateauing at the carrying capacity to create an s-shaped curve
/.Carrying capacity (K) - Answer-the max population size of a species that the
environment and resources can sustain indefinitely
/.When population N is small - Answer-The expression (K-N)/K becomes (K/K), or 1,
giving us an exponential growth equation instead of logistic, so populations grow
exponentially until they become larger.
/.Delta-N/Delta-t = rN([K - N]/K) OR = rN(1 - N/K) - Answer-the Logistic Growth Formula
/.Logistic Growth Curve - Answer-
/.(K-N)/K values in logistic growth - Answer-When close to 0, the growth rate slows and
is near carrying capacity. When 0.5, the growth rate switches from exponential to
logistic, and is right in the middle of the curve. When close to 1, the growth rate is
exponential
/.Factors that determine range/area of a species - Answer-The ability to find a mate,
their capacity to acclimate to climate, their ability to find food and avoid predation, and
the underlying genetic variability of the population.
/.Demography - Answer-The statistical study of population dynamics and population
changes over time
/.Population size (N) - Answer-the total number of individuals
/.Population density - Answer-the number of individuals within a specific area/volume
/.Sex ratio - Answer-the ratio of males to females in a population. This can influence
things such as birth rates.
/.Age structure - Answer-The proportion of population members at specific age ranges
/.Life expectancy - Answer-The length of time individuals typically live. This impacts
local resources, reproduction, and the overall health of the population
A)
/Ecology - Answer-The study of interactions among organisms and their environment
/.Key population features - Answer-Distribution, growth, and size/density
/.Random distribution - Answer-When individuals in a population have an equal
probability of occurring anywhere, with no pattern. Ex: dandelions
/.Random distribution causes - Answer-Caused by neutral interactions between
individuals and the local environment
/.Uniform Distribution - Answer-Individuals are evenly spaced throughout the
environment. Ex: penguins
/.Uniform Distribution causes - Answer-Caused by antagonistic interactions between
individuals OR the local depletion of resources
/.Clumped distribution - Answer-Individuals live in areas of high local abundance
separated by areas of low abundance. Most common type. Ex: elephants or other herd
animals
/.Clumped distribution causes - Answer-Caused by attraction between individuals OR
attraction of individuals to a common resource
/.Allelopathy - Answer-Production of secondary compounds by plants that prevent
growth of other organisms around them, often seen in uniform distribution
/.Factors affecting population size - Answer-Births and immigration add, deaths and
emigration subtract
/.delta-N = N2 - N1 = (B - D) + (I - E) - Answer-The formula for population size change
/.r = (delta-N/delta-t)/N1 - Answer-Growth per Capita (intrinsic rate of growth) Formula
/.Nt = N1(1 + r)^t - Answer-Formula for the Size of a Population after a Set amount of
Time
/.Exponential growth - Answer-A pattern of data that shows greater increases with
passing time, creating a j-shaped curve
/.Delta-N/Delta-t = rN - Answer-the Exponential Growth Formula
, /.Exponential Curve - Answer-
/.Things that slow population growth - Answer-Diseases, competition over resources,
resource limitation, and predation. These are affected by population size.
/.Logistic growth - Answer-Population growth that is controlled by limited resources,
plateauing at the carrying capacity to create an s-shaped curve
/.Carrying capacity (K) - Answer-the max population size of a species that the
environment and resources can sustain indefinitely
/.When population N is small - Answer-The expression (K-N)/K becomes (K/K), or 1,
giving us an exponential growth equation instead of logistic, so populations grow
exponentially until they become larger.
/.Delta-N/Delta-t = rN([K - N]/K) OR = rN(1 - N/K) - Answer-the Logistic Growth Formula
/.Logistic Growth Curve - Answer-
/.(K-N)/K values in logistic growth - Answer-When close to 0, the growth rate slows and
is near carrying capacity. When 0.5, the growth rate switches from exponential to
logistic, and is right in the middle of the curve. When close to 1, the growth rate is
exponential
/.Factors that determine range/area of a species - Answer-The ability to find a mate,
their capacity to acclimate to climate, their ability to find food and avoid predation, and
the underlying genetic variability of the population.
/.Demography - Answer-The statistical study of population dynamics and population
changes over time
/.Population size (N) - Answer-the total number of individuals
/.Population density - Answer-the number of individuals within a specific area/volume
/.Sex ratio - Answer-the ratio of males to females in a population. This can influence
things such as birth rates.
/.Age structure - Answer-The proportion of population members at specific age ranges
/.Life expectancy - Answer-The length of time individuals typically live. This impacts
local resources, reproduction, and the overall health of the population
