Virus-Bacteria Diagnostic Test (VBD-Test) is three-tier diagnostic instrument for identification virus and bacteria topics. The purpose of this study was to determine the empirical validity of the VBD-Test and identify misconceptions of virus and bacteria topics in biology teachers in Malang using VBD-Test. The development research model used was the Treagust development model, namely (1) Defining content, (2) Obtaining information, and (3) Developing a diagnostic test. The empirical validity on the VBD-Test was carried out with the Pearson correlation test using Excel, while the reliability on the VBD-Test was carried out with a spearman brown split-half method using Anatest 4.0.2. There are six valid questions and eight invalid questions on the virus topic, while in bacteria topics, there are nine valid questions and six invalid questions. The results of the identification of the teacher’s concept of the virus topic were 33.33% understood the idea, 13.66% false positive, 35.53% false negative, 17.01% did not understand the concept, and 4.39% guessed. While the results of the identification of the teacher’s concept of bacteria topic were 30.13% understood the concept, 9.07% false positive, 227.63% false negative, 23.05% did not understand the concept, and 10.09% guessed. Based on these results, if identification misconception is not made to the teacher, then the misconception will not be known by the teacher on any material, and the learning material submitted by the teacher will remain a misconception so that students will have misconception.

Tannins are one polyphenol antioxidants which have higher molecular weight and having two ring aromatic group containing -OH. Antioxidant polyphenols in plants are potentially beneficial to human health as antibacterial, astringent, antidiarrheal, and antioxidant. The aim of this study was to identify tannins from 4 Pterydophyta species from Baluran National Park. This type of research is qualitative. The research sample consisted of rhizom and frond extracts of Pseudocyclosorus ochthodes, Dyopteris hirtipes, Phymatodes sp., and Pteris vittata. The extraction process was carried out using maceration method using 96% methanol and phytochemical screening was tested followed by TLC test. The results showed all samples were positive tannins and their Rf range were 0.62-0.86.

This research aims to find out the constraints of understanding students' concepts in IPA learning at the junior high school level. This research is a qualitative descriptive study. The study used a survey method using live interviews to science teacher subjects over the phone. The research was conducted in March 2019. Data analysis is done descriptively with the stages of data collection, data reduction, data presentation and withdrawal of conclusions. The results showed that there were changes in concepts that occurred before and after the study was implemented. Concept changes in students can be easy and difficult due to the student's early knowledge factors, learning motivation and learning materials. Misconceptions in learning can also occur in difficult category materials for students.

Open-ended test is one of the diagnostic tests that can be used to measure misconceptions in students. The use of open-ended tests will give students the freedom to write their reasons for choosing answers to multiplechoice options. The purpose of this study is to identify misconceptions of 21st century biology learning material for prospective biology teacher students in Malang State University. The development model used is the ADDIE development model. The sample used was 26 students of prospective biology teacher at Universitas Negeri Malang in the 7th semester. The results of the open-ended test analysis for innovative biology learning materials, life-based learning, and 21st-century learning characteristics experienced misconceptions of 23%, 19%, and 18%. The misconceptions experienced by these students are still relatively low because the percentage of misconceptions is still in the range of 0-30%. Based on the results of the analysis it can be seen that there are still students who have a different understanding from the general concept of experts. Students are expected to be able to increase their understanding of concepts by creating learning tools that have been assigned in the form of concept maps/mind maps/resumes.