Populations - Limiting Factors and the Sigmoid Curve

✓ Engaging powerpoint
✓ Recaps previous linked learning
✓ Graph exam technique focus
✓ Past paper questions and mark scheme

This lesson on Populations is designed for KS4 Science students enrolled in the CIE Cambridge IGCSE Biology 0610 (2023-25) course. This is the third and last lesson in the topic 19 Organisms and Their Environment.

The lesson recaps previous learning from other linked topics to ensure students have a strong foundation before diving into the material. It also includes concise and easy-to-understand information and a variety of quick assessment for learning tasks to help students solidify their understanding of the topic. Just glance through the PowerPoint presentation and you are ready to go! There are also lots of example exam questions taken from past papers to deepen students understanding of the topic.

Objectives

• Describe a population as a group of organisms of one species, living in the same area, at the same time
• Describe a community as all of the populations of different species in an ecosystem
• Describe an ecosystem as a unit containing the community of organisms and their environment, interacting together
• Identify and state the factors affecting the rate of population growth for a population of an organism, limited to food supply, competition, predation and disease
• Identify the lag, exponential (log), stationary and death phases in the sigmoid curve of population growth for a population growing in an environment with limited resources
• Interpret graphs and diagrams of population growth
• Explain the factors that lead to each phase in the sigmoid curve of population growth, making reference, where appropriate, to the role of limiting factors

This lesson would also be adaptable for all GCSE students (whether AQA, Edexcel, OCR) and great for KS3 Science or as a GCSE revision resource.