The implementation of the kurikulum 2013 requires of innovative and creative learning with the integration of technology in learning process. Teachers should be creative in finding and gathering learning resources, as well as making teaching materials needed in learning that can help students in learning to achieve goals in the curriculum. So it is necessary to develop learning media based on My Android Biology App in schools in learning biology. Especially in the food digestive system material can be motivate the student and the result of learning. The aim of this study is  (1) to analyze the validity of the My Biology App according to media experts and material experts, (2) to analyze the feasibility of the my biology app according to teacher and student responses, (3) to analyze student learning motivation and (4) to  analyze the result of learning at student. The method of research is Research and Development (R & D). Pre-Posttest Control Group is the research design. The results of the validation from media experts and material experts indicate that the learning media My Biology App is very valid. It appears in teacher responses with an average of 97.62 and student responses with an average of 108 with a percentage of 90% suitable for use in learning activities. The effectiveness is determined from the motivation data and student learning outcomes. 63% of students are highly motivated and 37% are motivated. The results of the posttest in the experimental class with an average of 86.96 greater than the posttest in the control class with an average of 83.25. In addition, the n-gain in the experimental class 0.74 is greater than the control class with an n-gain of 0.70. It can be concluded based on the results of research that the learning media My Biology App can increase motivation and student learning outcomes in the food digestive system material.

Lack of awareness and limited information about the dangers of e-cigarettes among teenagers, especially high school students, make them assume that e-cigarettes are a safe alternative to reduce smoking habit. This can be circumvented through the development of teaching materials that are tailored to the needs of students. This study aims to develop teaching materials about the negative effects of e-cigarettes as a source of learning for high school students and analyze their validity, readability, and feasibility. This development research uses the plot of Thiagarajan et al., (1974), namely 4-D (Define, Design, Develop, Disseminate). The subjects of this research include material & media experts, students of class XI MIPA 3 and XI MIPA 4 SMAN 12 Semarang, and teachers who are members of senior high school biology teachers forum in Rembang Regency. The results showed the validation scores of material and media experts were 83% and 97.7%, respectively, with very valid criteria. Analysis of the readability of teaching materials from the results of student responses and the cloze test, respectively obtained an average score of 86.2% and 84% with very good and independent criteria. Analysis of the feasibility of teaching materials from the results of teacher responses at the senior high school biology teachers forum in Rembang, obtained an average score of 83.7% with very feasible criteria. Based on the results of the study, it can be concluded that teaching materials about the negative effects of e-cigarettes are valid, it has good readability, and feasible to use as a source of learning for high school students. The teaching material is expected to be able to add insight and knowledge about the negative effects of e-cigarette exposure and to contribute better in improving the quality of learning resources.

Electric cigarettes are cigarettes that are used with battery power, but do not burn tobacco like ordinary cigarette products. Electric cigarettes were initially said to be safe for health because nicotine solutions contained in e-cigarettes only consist of a mixture of water, propylene glycol, flavor enhancing substances, the aroma of tobacco, and other compounds that do not contain tar, tobacco or other toxic substances common in tobacco cigarettes. Electric cigarettes contain free radical compounds that can cause oxidative stress. In conditions of oxidative stress, free radical compounds increase lipid peroxide. In normal enzyme activity, an increase in the concentration of substrate, namely the molecule hydrogen peroxide (H2O2) can increase enzyme activity. But when the active side of all enzymes binds to the substrate, the addition of the substrate cannot increase the speed of the next enzyme reaction, resulting in a decrease in enzyme activity. This study aimed to analyze the levels of GPx and catalase in rat blood exposed to electrocution cigarettes. The study was conducted on 30 male white rats of Wistar strain which were divided into 5 groups, namely K- (negative control), K + (positive control), KP1 (treatment 1), KP2 (treatment 2) and KP3 (treatment 3). The K + group is a positive control group with 3 cigarettes and KP1, KP2, KP3 electric cigarette treatment groups treated with e-cigarettes with a dose of nicotine 3 mg, 6 mg, 9 mg for 30 days. To find out the difference in GPx and catalase levels, each group was analyzed by using one way annova and LSD for parametric test, while for non-parametric tests using the kruskal wallis test and Mann Whitney test. The results of the analysis showed that all between groups K-, K +, KP1, KP2 and KP3 were significantly different, in the KP3 group had the level of Gpx (40.25 ± 2.03e) and catalase (2.46 ± 9.50e) which was the lowest due to exposure electric cigarette with the highest dose of nicotine which is 9 mg. Keywords: Electric cigarettes, GPx, catalase, Rokok elektrik, GPx, katalase   Rokok elektrik adalah rokok yang digunakan dengan tenaga baterai, namun tidak membakar tembakau seperti produk rokok biasa. Rokok elektrik pada awalnya dikatakan aman bagi kesehatan karena larutan nikotin yang terdapat pada rokok elektrik hanya terdiri dari campuran air, propilen glikol, zat penambah rasa, aroma tembakau, serta senyawa-senyawa lain yang tidak mengandung tar, tembakau atau zat-zat toksik lain yang umum terdapat pada rokok tembakau. Rokok elektrik mengandung senyawa radikal bebas yang dapat menyebabkan stress oksidatif. Pada kondisi stress oksidatif, senyawa radikal bebas meningkatkan peroksida lipid. Dalam aktivitas enzim yang normal, peningkatan konsentrasi subtrat, yaitu molekul hidrogen peroksida (H2O2) dapat meningkatkan aktivitas enzim. Namun pada saat sisi aktif semua enzim berikatan dengan substrat, penambahan substrat tidak dapat meningkatkan kecepatan reaksi enzim selanjutnya, sehingga terjadi penurunan aktivitas enzim. Penelitian ini bertujuan untuk menganalisis kadar GPx dan katalase pada darah tikus yang dipapar rokok elktrik. Penelitian dilakukan pada 30 ekor tikus putih jantan galur Wistar yang dibagi menjadi 5 kelompok, yaitu K- (kontrol negatif), K+ (kontrol positif), KP1 (perlakuan 1), KP2 (perlakuan 2) dan KP3 (perlakukan 3). Kelompok K+ merupakan kelompok kontrol positif dengan perlakuan rokok elektrik 3 batang dan kelompok KP1, KP2, KP3 merupakan kelompok perlakukan dengan rokok elektrik dosis nikotin 3 mg, 6 mg, 9 mg selama 30 hari. Untuk mengetahui perbedaan kadar GPx dan katalase setiap kelompok dilakukan analalisis data menggunakan uji one way annova dan LSD untuk parametrik sedangkan untuk non parametrik menggunakan uji kruskal wallis dan uji mann whitney. Hasil analisis menunjukkan semua antar kelompok K-, K+, KP1, KP2 dan KP3 berbeda nyata, pada kelompok KP3 memiliki kadar Gpx (40,25 ± 2,03e) dan katalase (2,46 ± 9,50e) yang paling rendah akibat dipapar rokok elektrik dengan dosis nikotin paling tinggi yaitu 9 mg. Keywords: Electric cigarettes, GPx, catalase, Rokok elektrik, GPx, katalase

Background and Objective: E-cigarettes (e-cig) produce smoke with high levels of free oxidants, which can be eliminated by endogenous antioxidants such as glutathione peroxidase (GPx) and catalase (CAT) in the human body. The GPx catabolizes hydrogen peroxide (H 2 O 2 ), while catalase counteracts free radicals by catalyzing H 2 O 2 into H 2 O and O 2 . However, oxidative stress is shown in the imbalance condition between free oxidants and endogenous antioxidants. The effect of e-cigarette smoking on the human body has not been discovered. Therefore, this research aimed to analyze the levels of GPx and CAT in the rat blood exposed to e-cig. Materials and Methods: The exposure to smoke with nicotine 3, 6 and 9 mg was applied to 30 rats divided into five groups for 30 days. The analysis results by one-way ANOVA showed significant differences in the GPx and CAT levels between the control and treatment groups. Nicotine at 9 mg gave the GPx level at 40.25±2.03 U mgG 1 and CAT at 2.46±0.50 nmol mLG 1 . Results: The results indicated that e-cigarette smoke reduced the levels of endogenous antioxidants in rat blood. Moreover, the body weight of rats increased and decreased due to the unstable metabolic rate. Conclusion: Exposure to e-cigarette smoke has an effect on reducing glutathione peroxidase (GPx) and catalase (CAT) levels in rat blood.