POPULATIONS LESSON 1 Specification point 3.4.1: - A population is all the organisms of one species in a habitat. - Populations of different species form a community. - Within a habitat a species occupies a niche governed by adaptation to both biotic and abiotic conditions. - Population size may vary as a result of the effect of abiotic factors interactions between organisms: interspecific and intraspecific competition and predation.

Lets get started: Ecosystems  Look at the key terms. Match up the words to the definitions. Outcomes:  Define the terms population, habitat, community, niche.  Give examples of different abiotic and biotic conditions.  Explain the link between the terms adaptation, abiotic conditions, biotic conditions and niche.  Suggest ways in which ecosystems are affected by both abiotic and biotic conditions and identify these on population growth curves.

Abiotic and Biotic Conditions  Sort these environmental conditions into biotic and abiotic conditions: Air and water temperature Competition Predationrainfall soil fertility diseaselight intensityshelter water availabilityfood availability HumiditypH Outcomes:  Define the terms population, habitat, community, niche.  Give examples of different abiotic and biotic conditions.  Explain the link between the terms adaptation, abiotic conditions, biotic conditions and niche.  Suggest ways in which ecosystems are affected by both abiotic and biotic conditions and identify these on population growth curves.

Niches, Adaptation, Biotic factors and Abiotic factors  How do these words link? 1. no two species have the same niche 2. Some species appear similar but have different niches 3. Adaptations help organisms avoid competition and aid them in harsh physical conditions 4. Competition is an example of a biotic factor 5. Physical conditions are abiotic factors. Write a paragraph explaining how the relationship between the terms niche, adaptation, biotic and abiotic factors. Outcomes:  Define the terms population, habitat, community, niche.  Give examples of different abiotic and biotic conditions.  Explain the link between the terms adaptation, abiotic conditions, biotic conditions and niche.  Suggest ways in which ecosystems are affected by both abiotic and biotic conditions and identify these on population growth curves.

Population Growth Curves  Most populations will follow this growth curve pattern. TASK: Can you identify and explain the different stages here in this growth curve Outcomes:  Define the terms population, habitat, community, niche.  Give examples of different abiotic and biotic conditions.  Explain the link between the terms adaptation, abiotic conditions, biotic conditions and niche.  Suggest ways in which ecosystems are affected by both abiotic and biotic conditions and identify these on population growth curves.

Population Growth Curves 1. Population numbers are low. It takes time for small numbers to reproduce and increase population. Resources needed are plenty, no competition. 2. Period of rapid growth in population. Resources still plenty and population size doubles with each interval. 3. Rate of growth slows down and population becomes stable. Limiting factors have limited any net growth in population. Resources used up and competition increases. Abiotic conditions may have changed. 4. What eventually could happen? Outcomes:  Define the terms population, habitat, community, niche.  Give examples of different abiotic and biotic conditions.  Explain the link between the terms adaptation, abiotic conditions, biotic conditions and niche.  Suggest ways in which ecosystems are affected by both abiotic and biotic conditions and identify these on population growth curves.

HW: Due next week Research and report in detail on how each of these biotic and abiotic factors influence population sizes. 1. Temperature 2. Competition 3. Light 4. Predation 5. pH 6. Water availability I have seen far too often internet copied work. I have software that detects Plagiarism. Don’t do it! Outcomes:  Define the terms population, habitat, community, niche.  Give examples of different abiotic and biotic conditions.  Explain the link between the terms adaptation, abiotic conditions, biotic conditions and niche.  Suggest ways in which ecosystems are affected by both abiotic and biotic conditions and identify these on population growth curves.