Bio 370 Exam 2 Question and answers
rated A+ 2025/2026
Populations: - correct answer ✔group of interacting individuals of the same species living a particular
area in time.
Age structure: - correct answer ✔relative frequency of individuals in different age classes
Cohort: - correct answer ✔group of individuals of the same age
Life tables - correct answer ✔help us determine the age structure of a population and predict changes
in the population size. Two types
Cohort life table: - correct answer ✔follows the fate of a group of individuals in the same cohort
through time.
Survival rate (Sx ): - correct answer ✔chance that the individuals of age x will survive to age x+1
Survivorship tables - correct answer ✔First presentation review and do practice problems
Survivorship (I x ): - correct answer ✔proportion of individuals that survive from birth to age x.
Births (bx ): - correct answer ✔total number of offspring produced by females at age x. Note: can only
use if you know the number of offspring
Fecundity (Fx ): - correct answer ✔average number of offspring produced per surviving female at age x.
, Net reproductive rate of population (R0 ): - correct answer ✔mean number of offspring produced by an
individual in its life time.
R0 = I x * Fx - correct answer ✔R0 < 1 : population is decreasing R0 = 1 : population is stable R0 > 1 :
population is growing
Generation time (G): - correct answer ✔average age of the parents of all the offspring produced within
the cohort.
Static life table: - correct answer ✔survival and reproduction of individuals of different ages in a
population at a single time period
Type I: - correct answer ✔most individuals survive to old age
Type II: - correct answer ✔chance of survival remains constant throughout lifetime
Type III: - correct answer ✔low survival for young, the few that reach adulthood survive long
Review - correct answer ✔Life tables show how survival and reproductive rates vary with age, size, or
life cycle stage. There are two types of life tables: cohort and static Populations can have different
survivorship curves depending on the environmental conditions they experience Survivorship curves can
also reflect general life history strategies (r-selected versus K-selected) Practice the life table exercises
on Moodle
Population change is distilled to: - correct answer ✔Nt+1 = Nt + B - D + I - E
Births (B)
Immigration (I)
Emigration (E)
Deaths (D)
rated A+ 2025/2026
Populations: - correct answer ✔group of interacting individuals of the same species living a particular
area in time.
Age structure: - correct answer ✔relative frequency of individuals in different age classes
Cohort: - correct answer ✔group of individuals of the same age
Life tables - correct answer ✔help us determine the age structure of a population and predict changes
in the population size. Two types
Cohort life table: - correct answer ✔follows the fate of a group of individuals in the same cohort
through time.
Survival rate (Sx ): - correct answer ✔chance that the individuals of age x will survive to age x+1
Survivorship tables - correct answer ✔First presentation review and do practice problems
Survivorship (I x ): - correct answer ✔proportion of individuals that survive from birth to age x.
Births (bx ): - correct answer ✔total number of offspring produced by females at age x. Note: can only
use if you know the number of offspring
Fecundity (Fx ): - correct answer ✔average number of offspring produced per surviving female at age x.
, Net reproductive rate of population (R0 ): - correct answer ✔mean number of offspring produced by an
individual in its life time.
R0 = I x * Fx - correct answer ✔R0 < 1 : population is decreasing R0 = 1 : population is stable R0 > 1 :
population is growing
Generation time (G): - correct answer ✔average age of the parents of all the offspring produced within
the cohort.
Static life table: - correct answer ✔survival and reproduction of individuals of different ages in a
population at a single time period
Type I: - correct answer ✔most individuals survive to old age
Type II: - correct answer ✔chance of survival remains constant throughout lifetime
Type III: - correct answer ✔low survival for young, the few that reach adulthood survive long
Review - correct answer ✔Life tables show how survival and reproductive rates vary with age, size, or
life cycle stage. There are two types of life tables: cohort and static Populations can have different
survivorship curves depending on the environmental conditions they experience Survivorship curves can
also reflect general life history strategies (r-selected versus K-selected) Practice the life table exercises
on Moodle
Population change is distilled to: - correct answer ✔Nt+1 = Nt + B - D + I - E
Births (B)
Immigration (I)
Emigration (E)
Deaths (D)
