C4.1 Populations and Communities

Define population.

C4.1.1 - Populations as interacting groups of organisms of the same species living in an area.

A group of organisms of the same species who live in the same area at the same time and interbreed with each other.

State what isolates populations of the same species.

C4.1.1 - Populations as interacting groups of organisms of the same species living in an area.

Reproductive isolation.

Define sample.

​C4.1.2 - Estimation of population size by random sampling.

Define the purpose of sampling a population.

​C4.1.2 - Estimation of population size by random sampling.

Define sampling error.

​C4.1.2 - Estimation of population size by random sampling.

Describe the need for randomness in sampling procedures.

​C4.1.2 - Estimation of population size by random sampling.

Compare sampling methods for sessile vs motile organisms.

​C4.1.2 - Estimation of population size by random sampling.

Outline the use of quadrat sampling to estimate the population of sessile organism.

C4.1.3 - Random quadrat sampling to estimate population size for sessile organisms.

Describe the method of capture-mark-release-recapture sampling to estimate the population of motile organisms.

C4.1.4 - Capture–mark–release–recapture and the Lincoln index to estimate population size for motile organisms.

List assumptions made about the population when using mark-recapture methods to estimate population size.

C4.1.4 - Capture–mark–release–recapture and the Lincoln index to estimate population size for motile organisms.

Outline the use of Lincoln index to estimate population size from mark-recapture data.

C4.1.4 - Capture–mark–release–recapture and the Lincoln index to estimate population size for motile organisms.

Define carrying capacity.

​C4.1.5 - Carrying capacity and competition for limited resources. 

The maximum number of individuals that a particular habitat can support.

List examples of resources that may limit the carrying capacity of a population.

​C4.1.5 - Carrying capacity and competition for limited resources. 

Outline population size control as an example of a negative feedback loop.

C4.1.6 - Negative feedback control of population size by density-dependent factors.

Distinguish between density-dependent and density-independent factors that control population size.

C4.1.6 - Negative feedback control of population size by density-dependent factors.

List examples of density-dependent factors that maintain population carrying capacity.

C4.1.6 - Negative feedback control of population size by density-dependent factors.

Outline examples of density-independent factors that maintain population carrying capacity.

C4.1.6 - Negative feedback control of population size by density-dependent factors.

State that species have the ability to produce more offspring than the environment can support.

C4.1.7 - Population growth curves.

Outline conditions in which populations can grow exponentially.

C4.1.7 - Population growth curves.

Explain the reasons for the pattern of sigmoid population growth curve.

C4.1.7 - Population growth curves.

Sketch and annotate a graph of the sigmoid and exponential growth curves.

C4.1.7 - Population growth curves.

Outline the use of a logarithmic scale when plotting change in population over time.

C4.1.7 - Population growth curves.

Outline a method for monitoring the population of yeast or duckweed over time.

​C4.1.8 - Modelling of the sigmoid population growth curve. 

Use data of yeast or duckweed population over time to compare observe and expected population growth curves.

​C4.1.8 - Modelling of the sigmoid population growth curve. 

Define intraspecific relationship.

C4.1.9 - Competition versus cooperation in intraspecific relationships.

Outline cause and effect of competition in a population.

C4.1.9 - Competition versus cooperation in intraspecific relationships.

Outline cause and effect of cooperation in a population.

C4.1.9 - Competition versus cooperation in intraspecific relationships.

List examples of competition and cooperation in plant and animal populations.

C4.1.9 - Competition versus cooperation in intraspecific relationships.

Define community and give an example of a community of organisms.

C4.1.10 - A community as all of the interacting organisms in an ecosystem.

Outline the ecological interactions within biological communities and state an example.

C4.1.11 - Herbivory, predation, interspecific competition, mutualism, parasitism and pathogenicity as categories of interspecific relationship within communities.

Outline the mutualistic relationship within root nodules in Fabaceae (legume family).

​​​C4.1.12 - Mutualism as an interspecific relationship that benefits both species.

Outline the mutualistic relationship within mycorrhizae in Orchidaceae (orchid family).

​​​C4.1.12 - Mutualism as an interspecific relationship that benefits both species.

Outline the mutualistic relationship of zooxanthellae in hard corals.

​​​C4.1.12 - Mutualism as an interspecific relationship that benefits both species.

Define endemic and invasive species.

C4.1.13 - Resource competition between endemic and invasive species.

Describe the effect of invasive species on the realized niche of an endemic species.

C4.1.13 - Resource competition between endemic and invasive species.

Outline the competition for resources in an example of endemic and invasive species.

C4.1.13 - Resource competition between endemic and invasive species.

Explain the methodology and limitations of using a chi-square test to assess presence of interspecific competition in a community.

C4.1.14 - Tests for interspecific competition.

Explain the use of direct experimentation to assess the presence of interspecific competition in a community.

C4.1.14 - Tests for interspecific competition.

State the null and alternative hypothesis of the chi-square test of association between species in a community.

C4.1.15 - Use of the chi-squared test for association between two species.

Use a contingency table to complete a chi-square test of association between species in a community.

C4.1.15 - Use of the chi-squared test for association between two species.

Explain the typical dynamic equilibrium of populations of predator and prey.

C4.1.16 - Predator-prey relationships as an example of density-dependent control of animal populations.

Describe an example of an oscillating cycle of predator and prey population sizes.

C4.1.16 - Predator-prey relationships as an example of density-dependent control of animal populations.

Compare and contrast top-down and bottom-up control of populations in communities.

C4.1.17- Top-down and bottom-up control of populations in communities.

Define allelopathy.

​​​​C4.1.18 - Allelopathy and secretion of antibiotics.

Outline an example of allelopathy.

​​​​C4.1.18 - Allelopathy and secretion of antibiotics.

Define antibiotics.

​​​​C4.1.18 - Allelopathy and secretion of antibiotics.

Outline an example of the natural production and function of antibiotics.

​​​​C4.1.18 - Allelopathy and secretion of antibiotics.