Biology Extended Essay Exemplar: To what extent does capsaicin… | RevisionDojo

Loading document preview...

IB Biology HL Extended Essay Example

To what extent does capsaicin extracted from different chilli pepper species (Green Chilli, Bedgi Chili, Gundu Chilli, Bullet Chilli & Picador Chilli) inhibit lipase activity, measured by the mass of fatty acids produced from milk via NaOH titration and pH change over 30 minutes?HL

Official IB Result

IB Grade: B

Criteria A: Focus and Method

4/6

Criteria StrandsPro

A.1Topic communication and explanation

Good

A.2Research question formulation and focus

Moderate

A.3Methodology appropriateness and completeness

Moderate

Criteria Feedback

The student communicates the overall biological investigation clearly, so the reader can follow what they are testing and why.
The student's research question is explicit and gives the study a clear experimental direction.
The student includes a relevant range of methods and controls, including repeated trials, a no-extract control, and attention to variables and uncertainty.

The investigation is only partially focused because it claims to test capsaicin, but the method actually uses crude chilli extracts rather than measured capsaicin.
Some explanatory material drifts away from the research focus, which weakens the clarity of the line of inquiry.
Several methodological choices are not fully justified or controlled, such as the use of SHU as a proxy, the ethanol step, and the starting pH differences.

Criteria B: Knowledge and Understanding

4/6

Criteria StrandsPro

B.1Application of source material

Moderate

B.2Use of terminology and concepts

Moderate

Criteria Feedback

The student uses a good range of biological terminology accurately in many places, including lipase, triglycerides, fatty acids, inhibition, control, and standard deviation.
The student's explanation of the core lipase reaction is relevant and helps ground the investigation in appropriate biological knowledge.
The student makes a genuine effort to connect source material to the investigation and to support the background and procedure with research.

Some biology is described inaccurately, such as treating digestion as anabolic rather than catabolic.
The student sometimes presents mechanistic claims too confidently, especially where the evidence does not securely establish capsaicin as a proven inhibitor in this system.
The student's use of source material is only partly effective because some claims are extended beyond what the sources can directly support.

Criteria C: Critical Thinking

8/12

Criteria StrandsPro

C.1Research analysis

Moderate

C.2Discussion and evaluation

Poor

C.3Argument development

Moderate

Criteria Feedback

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.
Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Criteria D: Presentation

3/4

Criteria StrandsPro

D.1Structure appropriateness

Good

D.2Layout and formatting

Good

Criteria Feedback

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.
Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Loading scores...

Official IB Result

IB Grade: B

Criteria A: Focus and Method

4/6

Criteria StrandsPro

A.1Topic communication and explanation

Good

A.2Research question formulation and focus

Moderate

A.3Methodology appropriateness and completeness

Moderate

Criteria Feedback

The student communicates the overall biological investigation clearly, so the reader can follow what they are testing and why.
The student's research question is explicit and gives the study a clear experimental direction.
The student includes a relevant range of methods and controls, including repeated trials, a no-extract control, and attention to variables and uncertainty.

The investigation is only partially focused because it claims to test capsaicin, but the method actually uses crude chilli extracts rather than measured capsaicin.
Some explanatory material drifts away from the research focus, which weakens the clarity of the line of inquiry.
Several methodological choices are not fully justified or controlled, such as the use of SHU as a proxy, the ethanol step, and the starting pH differences.

Criteria B: Knowledge and Understanding

4/6

Criteria StrandsPro

B.1Application of source material

Moderate

B.2Use of terminology and concepts

Moderate

Criteria Feedback

The student uses a good range of biological terminology accurately in many places, including lipase, triglycerides, fatty acids, inhibition, control, and standard deviation.
The student's explanation of the core lipase reaction is relevant and helps ground the investigation in appropriate biological knowledge.
The student makes a genuine effort to connect source material to the investigation and to support the background and procedure with research.

Some biology is described inaccurately, such as treating digestion as anabolic rather than catabolic.
The student sometimes presents mechanistic claims too confidently, especially where the evidence does not securely establish capsaicin as a proven inhibitor in this system.
The student's use of source material is only partly effective because some claims are extended beyond what the sources can directly support.

Criteria C: Critical Thinking

8/12

Criteria StrandsPro

C.1Research analysis

Moderate

C.2Discussion and evaluation

Poor

C.3Argument development

Moderate

Criteria Feedback

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.
Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Criteria D: Presentation

3/4

Criteria StrandsPro

D.1Structure appropriateness

Good

D.2Layout and formatting

Good

Criteria Feedback

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.
Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.