In this stage, interviews with biology teachers of grade XI are conducted to understand aspects related to the learning process, the use of learning media, and the difficulties encountered by students in the learning process at school.

In this stage, testing of the external bleeding cessation activity using ethanolic extract of sungkai leaves (Peronema canescens Jack.) is conducted. The results will be included in the learning video, along with an analysis of the sequence of learning stages in the circulatory system material.

The development of learning video is planned using the Canva application. This stage involves the analysis of learning objectives, creation of storyboards, scenario development, and completion of video production.

An assessment is conducted to determine the feasibility and validity of the learning video developed using the content validity coefficient method.

In this stage, revisions are made to the learning video based on the discussions with validators.

The last stage, which is product creation, the learning video is produced based on the previously validated design by validators.

The instruments used in this research are teacher interview sheets for the analysis of media development needs, instrument validation sheets, and learning media validation sheets. The media validation sheets used have been previously validated by validators using instrument validation sheets.

The data collected in this study comprises qualitative and quantitative data. Qualitative data is derived from interview findings and instrument validation outcomes, while quantitative data is sourced from learning media validation results. The qualitative data from interviews and instrument validation, including comments, suggestions, and inputs, are summarized and selected based on their relevance to the research objectives. The analysis of learning media validation data utilizes the Content-validity Coefficient (Aiken’s V) method as per (Aiken, 1985). The Aiken V index is a measure of rater agreement on the appropriateness of items to measure the intended indicators (Retnawati, 2016). The formula utilized is as follows:

Description:

V = validation score

S = r- Lo

r = the score given by the assessor Lo = the lowest assessment score

C = the highest assessment score n = the number of assessors

The final result of the calculation of Aiken’s V coefficient will determine the feasibility and validity of the learning video. The interpretation of the Aiken validity index used refers to (Nabil et al., 2022), as presented in Table 1.

External bleeding occurs when the body's surface is injured and blood is released (Sidrotullah, 2021). The cessation of bleeding is usually done by administering chemical hemostatic drugs such as tranexamic acid, but long-term and repeated administration can cause side effects (Purwoko et al., 2022). The use of medicinal plants can be an alternative to replace the use of chemical drugs because besides having fewer side effects, medicinal plants are easily obtainable and more affordable (Kumontoy et al., 2023).

Indonesian society has long utilized natural resources for survival, including for stopping external bleeding (Sidrotullah, 2021); (Sutopo et al., 2016) . The sungkai plant is one of the plant species utilized in traditional medicine or healthcare. Based on phytochemical test results, sungkai leaf extract contains flavonoid compounds, saponins, and tannins that have the potential as hemostatic agents because they can shorten bleeding time (Emilia et al., 2023) .

The cessation of bleeding is related to blood clotting, which is studied in the circulatory system material for grade XI high school students. According to research conducted by Wahyuni (2020), the circulatory system material is one of the subjects that are difficult for students to understand because it involves many abstract concepts and is closely related to daily life. One way to overcome this issue is by using learning media that can visualize the material and provide concrete examples, making it easier to understand, such as learning videos (Mashuri & Budiyono, 2020).

The development of learning videos on the circulatory system material for grade XI high school students based on the activity test of external bleeding cessation using ethanolic extract of sungkai leaves (Peronema canescens Jack.) can be carried out to assist students in understanding the material. In addition to visualizing the material, learning videos on the circulatory system material incorporating research findings have not been developed previously.

The information gathered in this study is sourced from the results of the activity test of external bleeding cessation using ethanolic extract of sungkai leaves (Peronema canescens Jack.) and the analysis of the learning objectives flow in the circulatory system material. The test results indicate that the ethanolic extract of sungkai leaves has proven to have external bleeding cessation activity, characterized by a shorter bleeding time compared to the other groups. These test results are then included in the learning video which is linked to the discussion on blood clotting.

The hemostatic activity of ethanolic extract from sungkai leaves is caused by the presence of flavonoids, tannins, and saponins. Flavonoids function to increase platelet count and have vasoconstrictive effects that accelerate platelet aggregation, where platelets adhere to the vessel wall and form a plug, thereby expediting the hemostasis process. Tanins function to accelerate the release of fibrinogen proteins, which are transformed into fibrin threads from cells and deposited on the cell's surface. The faster fibrin threads form, the quicker the wound is sealed, stopping the blood flow. Similar to flavonoids and tannins, saponins induce vasoconstrictive effects and accelerate protein deposition. This relates to the blood clotting process: when there is a wound and blood flows out, platelets come into contact with the rough wound surface and rupture, releasing thrombokinase. Thrombokinase, along with calcium ions (Ca 2+ ) and vitamin K, converts prothrombin into thrombin. Thrombin then transforms fibrinogen into fibrin threads that obstruct the flow of blood cells, leading to blood clot formation.

In the analysis of the learning objectives flow stage, information is gathered regarding achievements, objectives, and learning material content. Based on the analysis results, the learning achievements consist of two elements: understanding biology and process skills. Furthermore, there are nine learning objectives for the learning material content, which include blood, organs of the circulatory system, School Biology Education mechanisms of circulation, blood types, blood transfusion, lymphatic system, the role of the circulatory system in the transport and exchange of substances, and circulatory system disorders.

After collecting information, the next step is to design the learning video using the Canva application. The learning video contains material on the circulatory system and the results of the activity test of external bleeding cessation using ethanolic extract of sungkai leaves (Peronema canescens Jack.), which is linked to the discussion on blood clotting. At the beginning of the video, there is a cover section shown in Figure 1 and the learning objectives shown in Figure 2.

Figure 1 illustrates that the cover page features the title of the learning video, "Circulatory System," targeted for use in Biology instruction for 11th-grade senior high school students or equivalent. It also includes the creator's identity, comprising the full name and institution, as well as information regarding the completeness of the video’s content, specifically highlighting the results of testing related to external bleeding cessation activities.

Figure 2 illustrates the learning outcomes for 11th-grade senior high school students according to the Merdeka Curriculum, categorized under Phase F. The learning outcomes consist of two elements: biological understanding and process skills.

Learning outcomes in the element of biological understanding at the end of phase F are that students have the ability to describe cell structures and bioprocesses such as membrane transport and cell division; analyze the relationship between organ structures in organ systems and their functions, as well as disorders or abnormalities that occur in these organ systems; understand enzyme functions and recognize metabolic processes that occur in the body; and have the ability to apply concepts of inheritance, growth and development, evaluate new ideas about evolution, and biological technology innovations.

The learning outcomes in the element of process skills consist of: 1) Observing, which involves the ability to select appropriate tools for measurement and observation, and to pay attention to relevant details of the observed object; 2) Questioning and predicting, which involves formulating scientific questions and hypotheses that can be investigated scientifically; 3) Planning and conducting investigations, where students plan and select appropriate methods based on references to collect reliable data, considering risks and ethical issues in the use of these methods. Students select and use tools and materials, including the use of appropriate digital technology to systematically and accurately collect and record data.

The content section of the developed learning video consists of five sessions. The first session covers the topic of blood, the second session discusses the organs of the circulatory system and the mechanism of circulation, the third session covers blood types and blood transfusions, the fourth session addresses the mechanism of blood clotting and the lymphatic system, and the fifth session discusses the role of the circulatory system in substance transport and circulatory system disorders. Each session is taught within a two-hour class period. Each session is distinguished by a divider, followed by learning objectives, learning materials, and the results of the activity test of external bleeding cessation using ethanolic extract of sungkai leaves (Peronema canescens Jack.). The content section of the learning video is shown in Figure 3.

Figure 3 illustrates the content structure of the learning video, which includes sections delineating the divisions between meetings labeled “Meeting 1”, differentiating between the first through fifth sessions. It outlines the learning objectives corresponding to the material covered in each session, for example students are able to analyze the components that make up blood and their functions. The learning video presents varied instructional content for each meeting for example material about blood that discusses the meaning of blood and blood characteristics. The learning video also includes the results of activity test of external bleeding cessation using ethanolic extract of sungkai leaves (Peronema canescens Jack).

In accordance with the objectives of developing the learning video, the objects

displayed are chosen to provide a realistic visualization according to their original form. The selection of objects used in the learning video is shown in Figure 4. Additionally, the learning video also presents concrete examples based on research findings, namely the cessation of external bleeding associated with the discussion of blood clotting, as shown in Figure 5.

Figure 4 demonstrates that the objects used in the learning video provide a realistic visualization consistent with their actual forms. For instance, red blood cells (erythrocytes) are depicted as concave or biconcave in shape, white blood cells (leukocytes) appear irregular and lighter in color, platelets (thrombocytes) are shown as irregularly shaped and colorless, and the heart is accurately represented within the body, positioned centrally in the chest, specifically on the left side of the torso.

Figure 5 presents a concrete example of research findings on the cessation of external bleeding using ethanolic extract of sungkai leaves (Peronema canescens Jack.). The study involved severing the tail of a rat that had previously been treated with the extract. The results illustrate the progression of external bleeding and its subsequent cessation, influenced by the components within the ethanolic extract of Sungkai leaves. These findings are then correlated with the blood coagulation process studied in the circulatory system module.

The developed product was initially validated to determine its suitability as an learning media (Matsun et al., 2019) . The validation process involves 5 validators. Learning media is validated using a validation sheet created beforehand. The validation sheet consists of four aspects: format aspect with two indicators, content aspect with three indicators, language aspect with three indicators, and presentation aspect with three indicators. The validation results are then analyzed using the Aiken V content validity coefficient method. The validation results of the learning video on the circulatory system material for grade XI high school students based on the activity test of external bleeding cessation using ethanolic extract of sungkai leaves (Peronema canescens Jack.) indicated a very high validity, as demonstrated by a validation score of 0.95. The validation results are shown inTable 2.

Table 2 presents the results of the learning video validation, which achieved an average score of 0.95, categorized as "very valid". This evaluation is based on four aspects: format, which includes two indicators; content, with three indicators; language, comprising three indicators; and presentation, containing three indicators. The discussion of the validation results for each aspect is presented as follows.

The format aspect consists of two indicators: systematic presentation and ease of understanding the overall content of the learning video. The first indicator, systematic presentation, obtained an average score of 1 with a category of very valid. This indicates that the content of the learning video is wellorganized, aligns with the learning activities, and presents the material from general to specific. This is in line with the findings of (Harefa et al., 2023) and (Zulfariyanti et al., 2022), who suggest that learning videos should be systematically structured and present the material sequentially to facilitate understanding by students. Similarly, according to (Luzyawati & Lissa, 2020), the material should be presented from general concepts to more specific ones to facilitate students in understanding the essence of the material.

The second indicator, which is the ease of understanding the overall content of the learning video, obtained an average score of

The second indicator, which is the ease of understanding the overall content of the learning video, obtained an average score of 0.93 with a category of very valid. This is because the segments of the learning video, the conveyed material, and the presentation of research findings are easily understood. However, the learning video does not yet include the division of material for each session, so this aspect was added during the design revision. According to (Wangkanusa et al., 2023) and (Zulfariyanti et al., 2022), learning videos should be easy to use and understand by anyone, especially students.

The content aspect consists of three indicators: alignment of the presented material with the learning outcomes and objectives, clarity of the conveyed concepts, and completeness of the presented material. The first indicator, alignment of the presented material with the learning outcomes and objectives, obtained an average score of 1, indicating a very valid category. This suggests that the material presented aligns with the nine learning objectives. Effective learning videos are structured according to the learning outcomes and objectives, facilitating focused learning (Zulfariyanti et al., 2022). Furthermore, they provide comprehensive material to aid students in directed learning (Gustinasari et al., 2017).

The second indicator, clarity of the conveyed concepts, received an average score of 0.93, indicating a very valid category. Overall, the concepts presented in the learning video are conveyed clearly. However, there is one topic in the video, the lymphatic system, which was considered unclear. Therefore, the explanation of this concept was improved during the design revision. According to (Gustinasari et al., 2019), clarity of concepts is crucial for enabling independent learning among students. Additionally, (Harefa et al., 2023) state that suitable learning media exhibit clear concepts, whether in written or graphical form.

The third indicator, completeness of the presented material, obtained an average score of 0.93, also falling under the very valid category. Although very valid, the score obtained for this indicator is not perfect, indicating that some material was not included in the learning video. Initially, the material covered included blood, the organs of the circulatory system, circulation mechanisms, blood types, blood transfusions, the lymphatic system, and circulatory system disorders. However, in alignment with the Merdeka Curriculum content, additional discussions on the role of the circulatory system in transport and exchange of substances were added. Material presented in learning media should be comprehensive to enable students to study directionally (Gustinasari et al., 2017) and to achieve the established learning objectives (Harefa et al., 2023)(Hasni et al., 2022).

The linguistic aspect encompasses three indicators: adherence to the General Spelling Guidelines of the Indonesian Language, clarity of sentence structures, and avoidance of linguistic ambiguity. The first indicator, compliance with grammar rules, received an average score of 0.8, indicating it falls within the valid category, as there were some errors in capitalization and italicization in the learning video. However, the video used standard terms, appropriate punctuation, and communicative language. These errors were later rectified during the design improvement phase. Effective learning media should adhere to proper linguistic conventions to aid students' comprehension (Panjaitan et al., 2022)(Salamah et al., 2020).

The second indicator, clarity of sentence structures, achieved an average score of 1, signifying it falls within the very valid category. This suggests that the sentences employed are effective, with complete sentence components and suitable vocabulary choices. Language utilized in learning media is considered proficient if it is straightforward, transparent (Panjaitan et al., 2022), and apt for explaining concepts and illustrations (Juniawati & Trimulyono, 2016).

The third indicator, avoidance of linguistic ambiguity, attained an average score of 1, also categorized as very valid. This indicates that the words utilized possess unambiguous meanings, and the language employed is devoid of confusion, minimizing the likelihood of misunderstanding. According to (Gustinasari et al., 2017) and (Panjaitan et al., 2021), appropriate media are those wherein sentence usage lacks linguistic ambiguity, thereby facilitating effortless comprehension by students.

The design aspect encompasses three key indicators: color, text, and image compatibility; font type and size selection; and the clarity of the narrative within the learning video. The first indicator, color, text, and image compatibility, scored an average of 1, indicating it falls within the very valid category. This suggests that the chosen colors contrast well, and the arrangement of text and images is harmonious, as depicted in Figure 6. The second indicator, font type and size selection, attained an average score of 0.87, also classified as very valid. This indicates that the chosen font types are visually appealing, although in some instances, legibility might be compromised. This aligns with the findings of (Dewi et al., 2024) and (Harefa et al., 2023), emphasizing the importance of selecting appropriate font styles and sizes for readability, incorporating attractive colors, and integrating relevant and well-designed graphics and illustrations.

Figure 6 illustrates the selection of contrasting colors between the background and the objects presented, ensuring clear visibility of the objects. The learning video's background predominantly features yellow and blue colors. Additionally, Figure 6 demonstrates that the layout of images and text is well-coordinated, which aids in material delivery and enhances the visual appeal of the learning video. The material presented in Figure 6 is the organs of the circulatory system which shows images of the heart and blood vessels, as well as the types of anemia, namely pernicious anemia, nutritional anemia, and aplastic anemia.

The third indicator, clarity of the narration in the learning video, attained an average score of 1, falling into the very valid category. This indicates that the narrator's voice is clear, with engaging intonation and suitable pacing, and that the narrator's voice and background music are well-balanced. This aligns with (Hakim, 2017) and (Indrayani et al., 2021) assertion that a suitable learning video features clear narration, facilitating students' understanding of the presented material.

After the learning video was validated, the next step involved making improvements based on the discussion with the validator to address any errors and deficiencies in the initial product design. Suggestions and feedback received were used as guidance to enhance the learning video on the circulatory system topic for 11th-grade high school students, aiming to create a better product. The revisions are shown in Table 3.

Table 3 shown that the revision made to the learning video includes adding sections that were previously absent and improving existing content. Additions include adding content divisions for each session and including discussions on the role of the circulatory system in transport and exchange of substances. Additionally, improvements were made in the use of capital letters in spelling chemical names and italicized words in writting scientific names, as well as clarifying concepts in the discussion of the lymphatic system.

The validated design is then transformed into a product in the form of an learning video. The learning video developed has a duration of 46 minutes and 34 seconds. It is designed for instruction over five sessions, covering nine content areas: blood, the circulatory system organs, the blood circulation mechanism, blood types, blood transfusion, the blood coagulation mechanism, the lymphatic system, the role of the circulatory system in substance transport, and circulatory system disorders. The video is equipped with learning objectives and goals for each content area. In addition to the instructional material, the video includes results from activity test of external bleeding cessation using ethanolic extract of sungkai leaves (Peronema canescens Jack.), which is connected to the discussion on blood coagulation.

The video features text and images that support the instructional content. Overall, the video is primarily unidirectional; however, it includes one segment where students are prompted to answer questions related to blood typing.