UNIT 8 Ecological Systems

Unit Outline

IB Roadmap: A3, C4

Unity and Diversity (A)

Common ancestry has given living organisms many shared features while evolution has resulted in the rich biodiversity of life on Earth.

Interaction and Interdependence (C)

Systems are based on interactions, interdependence and integration of components. Systems result in the emergence of new properties at each level of biological organization.

Part 1: Populations

Syllabus Statements

A3.1.1 Variation between organisms as a defining feature of life

A3.1.2 Species as groups of organisms with shared traits

A3.1.3 Binomial system for naming organisms

A3.1.4 Biological species concept

A3.1.12 AHL Difficulties applying the biological species concept to asexually species and to bacteria that have horizontal gene transfer

A3.1.13 AHL Chromosome number as a shared trait within a species

A3.1.14 AHL Engagement with local plant or animal species to develop a dichotomous key

A3.1.15 AHL Identification of species from environmental DNA in a habitat using barcodes

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

C4.1.2 Estimation of population size by random sampling.

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

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

C4.1.7 Population growth curves.

C4.1.8 Modelling of the sigmoid population growth curve.

C4.1.9 Competition versus cooperation in intraspecific relationships.

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

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