IB Biology EE example: To investigate the effect of increasing concentration (volume/volume ratio) of malathion (0.1%,0.2%,0.3%,0.4%,0.5%) an insecticide, on the total chlorophyll content measured through a spectrophotometer at 630,691,664 and 647nm, total carotenoid content, measured at 470nm, and percentage inhibition on electron transport, measured by the rate of decolorization of DCPIP at 600nm, of Elodea canadensis.

Correct

Criterion A: The student outlines the topic of their study at the beginning of the essay, making its aim clear to the reader

Comment: The student clearly states the topic of the investigation on the title page. The aim is also clearly outlined at the beginning of the document, in section 1.2 Rationale of Study

Correct

Criterion A: The student outlines the topic of their study at the beginning of the essay, making its aim clear to the reader

Comment: The student clearly states the topic of the investigation on the title page. The aim is also clearly outlined at the beginning of the document, in section 1.2 Rationale of Study

Correct

Criterion A: The student establishes a clear context of the study, i.e it describes the relevant background information, purpose, and focus of the essay

Comment: The student's background information is clearly organized and easy to follow. The student does not provide unnecessary details or stray from the main point, which is to outline the properties of Elodea Canadensis, malathion, and carotenoids. This information helps the reader fully comprehend the results of the experiment and is necessary to establish a complete groundwork for the study.

Correct

Criterion A: The student establishes a clear context of the study, i.e it describes the relevant background information, purpose, and focus of the essay

Comment: The student's background information is clearly organized and easy to follow. The student does not provide unnecessary details or stray from the main point, which is to outline the properties of Elodea Canadensis, malathion, and carotenoids. This information helps the reader fully comprehend the results of the experiment and is necessary to establish a complete groundwork for the study.

Correct

Criterion A: The student establishes a clear context of the study, i.e it describes the relevant background information, purpose, and focus of the essay

Comment: The student's background information is clearly organized and easy to follow. The student does not provide unnecessary details or stray from the main point, which is to outline the properties of Elodea Canadensis, malathion, and carotenoids. This information helps the reader fully comprehend the results of the experiment and is necessary to establish a complete groundwork for the study.

Correct

Criterion A: The student establishes a clear context of the study, i.e it describes the relevant background information, purpose, and focus of the essay

Comment: The student's background information is clearly organized and easy to follow. The student does not provide unnecessary details or stray from the main point, which is to outline the properties of Elodea Canadensis, malathion, and carotenoids. This information helps the reader fully comprehend the results of the experiment and is necessary to establish a complete groundwork for the study.

Correct

Criterion A: The student establishes a clear context of the study, i.e it describes the relevant background information, purpose, and focus of the essay

Comment: The student's background information is clearly organized and easy to follow. The student does not provide unnecessary details or stray from the main point, which is to outline the properties of Elodea Canadensis, malathion, and carotenoids. This information helps the reader fully comprehend the results of the experiment and is necessary to establish a complete groundwork for the study.

Incorrect

Criterion A: The student poses a detailed and focused research question that they will attempt to answer with their study

Comment: The student's research question contains all necessary information, including the variables, units, and method of investigation, however, it is not in the form of a proper question. To improve, the student should have started with "How does (...)" and rephrased the sentence so that it could end with a question mark

Correct

Criterion A: The scope of the research question is appropriate to the availability of resources, time, and the word limit

Comment: The student selected a suitable number of variables that produced an adequate number of data points. The investigation method (using a spectrophotometer) was also achievable in lab conditions.

Correct

Criterion A: The research question is directly relevant to Biology and does not include topics, terms or concepts from other subjects

Comment: The student's research question concerns plant growth, which complies with the IB course content, specifically the "Plant Systems" section

Incorrect

Criterion A: The reader is presented with the research question at the beginning of the essay

Comment: The student has attached their research question on the title page, however, as mentioned previously, it is improperly formed. To improve, the student should have attached a proper question finished with a question mark

Correct

Criterion A: The reader is provided with the necessary biology-specific background, allowing them to fully understand the study

Comment: The student offers a comprehensive biological context for their research by presenting scientific background on all elements of the research question: heightened malathion usage, attributes of Elodea canadensis and chlorophyll, and the inhibition of the electron transport chain. Furthermore, the student includes multiple figures to visually represent the information. This detail aids in the reader's complete understanding of the experiment results and is essential for reaching a thorough conclusion.

Correct

Criterion A: The reader is provided with the necessary biology-specific background, allowing them to fully understand the study

Comment: The student offers a comprehensive biological context for their research by presenting scientific background on all elements of the research question: heightened malathion usage, attributes of Elodea canadensis and chlorophyll, and the inhibition of the electron transport chain. Furthermore, the student includes multiple figures to visually represent the information. This detail aids in the reader's complete understanding of the experiment results and is essential for reaching a thorough conclusion.

Correct

Criterion B: The student states any technical or subject-specific terms alongside a clear explanation, demonstrating their knowledge and understanding of the topic

Comment: All subject-specific terms such as carotenoids, photosynthesis, chlorophyll or malathion are used correctly throughout the work and provided alongside a clear definition

Correct

Criterion A: The reader is provided with the necessary biology-specific background, allowing them to fully understand the study

Comment: The student offers a comprehensive biological context for their research by presenting scientific background on all elements of the research question: heightened malathion usage, attributes of Elodea canadensis and chlorophyll, and the inhibition of the electron transport chain. Furthermore, the student includes multiple figures to visually represent the information. This detail aids in the reader's complete understanding of the experiment results and is essential for reaching a thorough conclusion.

Correct

Criterion A: The reader is provided with the necessary biology-specific background, allowing them to fully understand the study

Comment: The student offers a comprehensive biological context for their research by presenting scientific background on all elements of the research question: heightened malathion usage, attributes of Elodea canadensis and chlorophyll, and the inhibition of the electron transport chain. Furthermore, the student includes multiple figures to visually represent the information. This detail aids in the reader's complete understanding of the experiment results and is essential for reaching a thorough conclusion.

Correct

Criterion B: The student states any technical or subject-specific terms alongside a clear explanation, demonstrating their knowledge and understanding of the topic

Comment: All subject-specific terms such as carotenoids, photosynthesis, chlorophyll or malathion are used correctly throughout the work and provided alongside a clear definition

Correct

Criterion A: The reader is provided with the necessary biology-specific background, allowing them to fully understand the study

Comment: The student offers a comprehensive biological context for their research by presenting scientific background on all elements of the research question: heightened malathion usage, attributes of Elodea canadensis and chlorophyll, and the inhibition of the electron transport chain. Furthermore, the student includes multiple figures to visually represent the information. This detail aids in the reader's complete understanding of the experiment results and is essential for reaching a thorough conclusion.

Correct

Criterion A: The reader is provided with the necessary biology-specific background, allowing them to fully understand the study

Comment: The student offers a comprehensive biological context for their research by presenting scientific background on all elements of the research question: heightened malathion usage, attributes of Elodea canadensis and chlorophyll, and the inhibition of the electron transport chain. Furthermore, the student includes multiple figures to visually represent the information. This detail aids in the reader's complete understanding of the experiment results and is essential for reaching a thorough conclusion.

Correct

Criterion B: The student states any technical or subject-specific terms alongside a clear explanation, demonstrating their knowledge and understanding of the topic

Comment: All subject-specific terms such as carotenoids, photosynthesis, chlorophyll or malathion are used correctly throughout the work and provided alongside a clear definition

Correct

Criterion A: An appropriate number of sources and/or methods selected have been listed to present a complete methodology

Comment: The research's Variables section includes segments that focus on identifying independent and dependent variables, specifying the controlled variables (along with the rationale for controlling them in Table 1). Next, the student offers a thorough and detailed explanation of the actual experimental method in section 2.

Correct

Criterion A: An appropriate number of sources and/or methods selected have been listed to present a complete methodology

Comment: The research's Variables section includes segments that focus on identifying independent and dependent variables, specifying the controlled variables (along with the rationale for controlling them in Table 1). Next, the student offers a thorough and detailed explanation of the actual experimental method in section 2.

Correct

Criterion A: An appropriate number of sources and/or methods selected have been listed to present a complete methodology

Comment: The research's Variables section includes segments that focus on identifying independent and dependent variables, specifying the controlled variables (along with the rationale for controlling them in Table 1). Next, the student offers a thorough and detailed explanation of the actual experimental method in section 2.

Correct

Criterion A: An appropriate number of sources and/or methods selected have been listed to present a complete methodology

Comment: The research's Variables section includes segments that focus on identifying independent and dependent variables, specifying the controlled variables (along with the rationale for controlling them in Table 1). Next, the student offers a thorough and detailed explanation of the actual experimental method in section 2.

Correct

Criterion A: An appropriate number of sources and/or methods selected have been listed to present a complete methodology

Comment: The research's Variables section includes segments that focus on identifying independent and dependent variables, specifying the controlled variables (along with the rationale for controlling them in Table 1). Next, the student offers a thorough and detailed explanation of the actual experimental method in section 2.

Correct

Criterion A: An appropriate number of sources and/or methods selected have been listed to present a complete methodology

Comment: The research's Variables section includes segments that focus on identifying independent and dependent variables, specifying the controlled variables (along with the rationale for controlling them in Table 1). Next, the student offers a thorough and detailed explanation of the actual experimental method in section 2.

Correct

Criterion A: The document clearly states the hypothesis or hypotheses that will be tested through the study

Comment: Achieved through the inclusion of the Hypothesis section, where three versions of the hypothesis are correctly stated and outlined, along with their alternative versions

Correct

Criterion A: The student makes their initiative and engagement evident in terms of planning the study, conducting the literature research, and selecting the most appropriate biological approach for collecting data

Comment: The student describes the preliminary trials conducted before the study in section 2.2. The changes resulting from the trials are clearly outlined, for example, the fact that the concentration needed to be lowered to avoid extreme blanching

Correct

Criterion A: The relevance of the methodology design and the choice of materials used is explained by the student

Comment: The student correctly justifies the methodology design through section 2.4 Methodology of exposure chosen, where the rationale behind choosing the procedure is justified: "(...) as typically horticulture crops are exposed to insecticides for this duration, after which they are harvested and consumed, hence this provided a good simulating model"

Correct

Criterion A: If experimental work is conducted, the methodology section includes enough details for the reader to recreate the study

Comment: The correct listing of the apparatus and materials should provide the reader with enough information, in theory, to replicate the same experiment using the same materials. The student's provided methodology is clear and encompasses all the essential steps.

Correct

Criterion A: If experimental work is conducted, the methodology section includes enough details for the reader to recreate the study

Comment: The correct listing of the apparatus and materials should provide the reader with enough information, in theory, to replicate the same experiment using the same materials. The student's provided methodology is clear and encompasses all the essential steps.

Correct

Criterion A: If experimental work is conducted, the methodology section includes enough details for the reader to recreate the study

Comment: The correct listing of the apparatus and materials should provide the reader with enough information, in theory, to replicate the same experiment using the same materials. The student's provided methodology is clear and encompasses all the essential steps.

Correct

Criterion A: If experimental work is conducted, the methodology section includes enough details for the reader to recreate the study

Comment: The correct listing of the apparatus and materials should provide the reader with enough information, in theory, to replicate the same experiment using the same materials. The student's provided methodology is clear and encompasses all the essential steps.

Correct

Criterion A: If experimental work is conducted, the methodology section includes enough details for the reader to recreate the study

Comment: The correct listing of the apparatus and materials should provide the reader with enough information, in theory, to replicate the same experiment using the same materials. The student's provided methodology is clear and encompasses all the essential steps.

Correct

Criterion A: If experimental work is conducted, the methodology section includes enough details for the reader to recreate the study

Comment: The correct listing of the apparatus and materials should provide the reader with enough information, in theory, to replicate the same experiment using the same materials. The student's provided methodology is clear and encompasses all the essential steps.

Correct

Criterion A: The student has successfully obtained a sufficient amount of relevant data (both primary and secondary)

Comment: The student has conducted six trials for five variables, yielding thirty data points, which is a sufficient amount to process. Additionally, all secondary data obtained and information provided aim to further the research into the study of the impact of the insecticides on water plants

Correct

Criterion B: The student only incorporates source material in their essay that is relevant and appropriate to the posed research question

Comment: The sources that explain the topic chosen and the specific species investigated, malathion and the electron transport chain, are suitable. The student utilizes secondary data to provide additional explanation for the research question and, in the latter part of the Extended Essay, to address it. Drawing from the source material, the student is able to develop the hypotheses and thoroughly analyze the results.