Unit 3 Test tInsurance Flashcards
List 3 characteristics of K-selected species
- reproduce many times
- heavy parental care
- long lifespan
Provide 2 examples of K-selected species
koalas, elephants
List 3 characteristics of R-selected species
- many offspring
- reproduce once
- no parental care
Provide 2 examples of r-selected species
salmon & ladybugs
Define biotic potential
The reproduction rate, the maximum reproductive capacity of an organism w/ optimum conditions
Discuss the biotic potential of salmon and whales
The biotic potential of salmon is high because they are an r-selected species that can produce many offspring. The biotic potential of whales is much lower because they are k-selected species that produce few offspring
Describe whether invasives species are generally k-selected or r-selected
Invasive species are generally r-selected species because their populations grow quickly and they develop adaptations faster because of their faster generation time.
Explain why invasive species follow the trend you indicated above
K-selected species reproduce much slower and their population sizes grow much less quick, so they are not the best invaders.
Explain why k-selected species are more negatively impacted by invasive species than r-selected species.
K-selected species are more negatively impacted by invasive species than r-selected species because their population sizes don’t grow as quickly.
Define the term age cohort
The term age cohort is a group of the same-aged individuals from a particular population
Define the term survivorship curve
line that shows the survival rate of a cohort
Describe each of the three survivorship curves (I, II, and III)
Type I: mostly k-selected which has a high survivorship until old age
Type II: medium animals which have a steady line of survivorship throughout life
Type III: mostly small organisms with low survivorship in the beginning and a slow decline the rest of their lives.
Provide an example of a species that follows each of the three survivorship curves
Type I: bears
Type II: lizard
Type III: ants
Explain why K-selected species generally follow survivorship curve I
K-Selected species tend to have more parental care, so offspring mostly survive when they’re young and they are able to defend themselves well once they get larger.
Explain why r-selected species generally follow survivorship curve III
R-Selected species generally don’t have any parental care so offspring are in greater risks of dying.
Define carrying capacity (k)
The carrying capacity is the maxmimum amount of organisms that an environment can sustain due to its resources
Describe how an ecosystem would change if a predator dies off? How would this influence genetic diversity of prey?
If predators die off, the population sizes of the prey would increase without predators there to hunt them. The prey may be able to flourish in numbers, but one could dominate over the other because there is only so many resources.
Describe overshoot using the example of deer in a temperate forest ecosystem
An overshoot would be the population size of the deer increasing too much and overating all of teh vegetation in the forest. This would mean the carrying capacity is reached by deer.
Explain the term dieback (or die off) using the example of deer in the temperate forest ecosystem 🦌🌳
A die-off would be when the population size of the deer overshoots and they overeat the vegetation. Since there is not enough for all the deer to eat, some of the deer would die.
Define limiting resource.
A limiting resource is a resource that has low quantities and is needed for a population to survive/reproduce.
Provide 3 examples of a limiting resource for a moose population in a boreal forest ecosystem
Mates, Vegetation, habitats
Define the term mortality
Death
Describe how decreasing resources impact the carrying capacity for a given population
Decreasing resources impact the carrying capacity because there are less resources. That means that less organisms can be sustained because there is not enough resources.
Explain why would food be considered a Density Dependent factor?
Food would be a density-dependent factor because the available food is dependent on the population size. With a greater population size, there are less resources available for the population to grow.
Explain the significance of the base (0-14 age cohorts) of an age structure diagram
The 0-14 age cohorts demonstrate the current population growth and the future populaiton growth. Whether it is declining, growing, or staying stable.
Explain the term population momentum
Population momentum is when the population size keeps growing after growth reduction measures have been implemented to decrease growth.
Explain why a larger age 15-44 population would cause a country to be concerned.
A larger 15-44 age population would mean that there is less children being produced which is a decline in population size. This means that the population size is becoming smaller.
Define total fertility rate
The total fertility rate is the average amount of children that a woman in her childbearing age is expected to have.
List 2 factors that influence total fertility rate
- access to contraceptives
- access to education
Define replacement level fertility rate
Replacement level fertility is the total fertility rate that is needed to keep the population size stable (after deaths).
Explain why replacement level fertility rate is higher in developing nations than in developed nations
The replacement level fertility rate is higher in developing nations
