Essential Idea:  The continued survival of living organisms including humans depends on sustainable communities.

• Outline answer to each objective statement for topic 4.1 (coming soon)
• Quizlet study set for this topic

At SHS, Topic 4.1 is taught in the following class unit(s):​​​​

• Concepts of Biology
• Speciation
• Communities and Ecosystems
• Energy Flow through Ecosystem
• Nutrient Cycles 

Statements & Objectives:

4.1.U1  Species are groups of organisms that can potentially interbreed to produce fertile offspring.​

• Describe limitations of the biological species concept.
• Define species according to the biological species concept.

4.1.U2  Members of a species may be reproductively isolated in separate populations.

• Define population.
• Outline how reproductive isolation can lead to speciation.

4.1.U3  Species have either an autotrophic or heterotrophic method of nutrition (a few species have both methods).

• Define autotroph and heterotroph.

4.1.U4  Consumers are heterotrophs that feed on living organisms by ingestion.

• Describe the feeding behaviors of consumers.
• List three example consumer organisms.​

4.1.U5  Detrivores are heterotrophs that obtain organic nutrients from detritus by internal digestion.

• Describe the feeding behaviors of detritivores.
• List two example detritivore organisms.

4.1.U6  Saprotrophs are heterotrophs that obtain organic nutrients from dead organisms by external digestion.​

• Describe the feeding behaviors of saprotrophs.
• List two example saprotroph organisms.

4.1.U7  A community is formed by populations of different species living together and interacting with each other.​

• Define species, population and community.
• Give an example of a community of organisms.

4.1.U8  A community forms an ecosystem by its interactions with the abiotic environment.

• Define abiotic and ecosystem.

4.1.U9  Autotrophs obtain inorganic nutrients from the abiotic environment.

• Define nutrient.
• List the common nutrients needed by organisms.
• Outline how nutrients enter living systems.

4.1.U10  The supply of inorganic nutrients is maintained by nutrient recycling.

• State that chemical elements can be recycled but energy can not.
• Outline the generalized flow of nutrients between the abiotic and biotic components of an ecosystem. ​

4.1.U11 Ecosystems have the potential to be sustainable over long periods of time.

• Define sustainability.​
• Give an example of an unsustainable practice.
• Outline three requirements of a sustainable ecosystem.

4.1.S1  Classifying species as autotrophs, consumers, detrivores or saprotrophs from a knowledge of their mode of nutrition.

• Use a dichotomous key to identify the mode of nutrition of an organism.​

4.1.S2  Testing for association between two species using the chi-squared test with data obtained from quadrat sampling.​

• Outline why sampling must be random.
• Explain methods of random sampling, including the use of a quadrat.
• State the null and alternative hypothesis of the chi-square test of association.
• Use a contingency table to complete a chi-square test of association.

4.1.S3  Recognizing and interpreting statistical significance.

• Calculate a chi-square statistic based on observed and expected values.  
• State the null and alternative hypothesis of statistical tests.
• Determine if the null hypothesis is supported or rejected given a critical value and a calculated statistic.
• State the minimum acceptable significance level (p value) in published research.
• Explain the meaning of a “statistically significant” result, including the probability of chance having a role in the result.

4.1.S4  Setting up sealed mecocosms to try to establish sustainability. (Practical 5)

• Define mesocosm.
• List three example mesocosms.
• Outline requirements of setting up a mesocosm.

4.1.NOS  Looking for patterns, trends and discrepancies- plants and algae are mostly autotrophic but some are not.

• State the trend found in the nutritional patterns of plants and algae.
• Describe the discrepancy in the nutritional pattern of parasitic plants and algae.