Biocaster : Jurnal Kajian Biologi

Studi Ekologi Komunitas Biotik Menggunakan Metode Relevé pada Berbagai Tipe Habitat di Kabupaten Polewali Mandar

2025-12-03T11:20:45+07:00

This study aims to analyze the structure and composition of biotic communities in various habitat types in Polewali Mandar Regency, West Sulawesi, using the relevé method. Observations were carried out in five sub-districts, namely Campalagian, Binuang, Tutar, Tapango, and Limboro. At each location, three plot sizes (1×1 m, 3×3 m, and 5×5 m) were set to compare species diversity based on the size of the sampling area. Data is collected by recording the presence of all organisms (plants and animals) present in the plot without counting the number of individuals in detail. The results showed that the number of species increased as the area of the plot increased, with a range of 3-7 species on a 1×1 m plot, 5-15 species on a 3×3 m plot, and 9-26 species on a 5×5 m plot. Several groups of organisms, such as pioneer herbaceous plants, shrubs, and generalist insects (e.g., Formicidae and Lepidoptera) were detected consistently across a wide range of plot sizes and habitats, indicating adaptability and wide distribution. Increased species richness on larger plots reflects the heterogeneity of microhabitats and the greater complexity of trophic interactions, thus supporting the principle of species-area relations in community ecology. This study provides basic data on biodiversity and biotic community structure in Polewali Mandar that can be used as a reference in conservation planning, sustainable natural resource management, and ecological policy development at the regional level.

Autofagi : Mekanisme Pemeliharaan Diri Sel dalam Kondisi Stres

2026-01-15T23:49:57+07:00

Autophagy is a cellular mechanism in the form of degradation and recycling of intracellular components that plays an important role in maintaining cell homeostasis, especially when cells are under stress conditions such as nutritional limitations, oxidative stress, organelle damage, or pathogen attacks. Through this process, cells are able to survive by eliminating damaged or dysfunctional structures, while simultaneously reusing the degradation products as a source of energy and building blocks for new molecules. This study aims to examine the mechanism of autophagy, the molecular regulations involved, and its role in the response to various forms of cellular stress using a literature review method. Reference sources in this study come from relevant scientific articles and are accessed through PubMed, Scopus, and Google Scholar databases with a publication year range of 2015-2024. Articles are selected based on the main inclusion criteria, namely discussions on the molecular pathway of autophagy, the process of autophagosome formation, and the role of lysosomes in cellular degradation mechanisms. The study results indicate that autophagy is an essential adaptive mechanism primarily controlled by the mTOR and AMPK pathways in response to cellular stress. Adaptive autophagy plays a crucial role in maintaining cell stability and survival, while autophagy dysfunction or uncontrolled activation is pathological and contributes to the development of various diseases, making autophagy a strategic therapeutic target. Furthermore, disruption of the autophagy process is known to be closely associated with the development of various degenerative and metabolic diseases, making autophagy a potential target in the development of biomedical therapeutic strategies.

Penerapan LKPD IPA Berbasis Peta Konsep untuk Meningkatkan Hasil Belajar Peserta Didik SMPN 1 Ende

2026-02-10T18:57:20+07:00

This research is motivated by the low learning outcomes of students due to learning strategies that tend to be one-way and less actively involve students. This study aims to determine the application of Student Worksheets (LKPD) based on concept maps on student learning outcomes on environmental pollution material in class VII of SMPN 1 Ende. This study uses a quantitative method with a true experimental design in the form of a randomized control group pretest-posttest design. The research subjects were 70 students consisting of 35 students in the experimental class and 35 students in the control class. The results showed that the average value of student learning outcomes in the experimental class increased significantly from 49.28 in the pre-test to 97 in the post-test, with an increase of 96.85%. While in the control class, the average value of learning outcomes increased from 50.6 in the pre-test to 64.11 in the post-test, with an increase of 26.71%. The t-test results showed a significance value of 0.000 ≤ 0.05, indicating a significant difference in learning outcomes between the experimental and control classes. Thus, the implementation of concept map-based student worksheets (LKPD) has been proven effective in increasing student activity, engagement, and learning outcomes.

Pengaruh Radiasi terhadap Struktur dan Fungsi Sel

2026-01-11T16:25:25+07:00

Ionizing and non-ionizing radiation are widely used in health, industry, scientific research, and communication technology, but their use also has the potential to pose biological risks to humans. Therefore, a comprehensive understanding of the mechanisms of radiation interaction with biological tissues and their health implications is crucial. This study aims to systematically examine the biological effects of ionizing and non-ionizing radiation on human health, as well as the safety principles applied in their use. The research method used is a literature review by examining scientific articles, reports from international institutions, and relevant publications that discuss radiation exposure, biological impacts, and aspects of radiation protection. The results of the study indicate that ionizing radiation, such as X-rays and gamma rays, has the ability to ionize atoms and molecules, thus potentially causing DNA damage that can trigger deterministic and stochastic effects, including an increased risk of cancer. Although radiation doses in medical diagnostic procedures are generally below the hazardous threshold, the application of radiation protection principles in the form of justification, optimization, and dose limitation remains a key factor in ensuring the safety of patients and healthcare workers. While non-ionizing radiation from telecommunications devices does not cause ionization, at high exposure levels it can cause thermal effects on biological tissue, although most epidemiological studies have not shown a consistent link with an increased risk of cancer. Exposure to cosmic radiation during commercial flights and at high altitudes has the potential to cause dose accumulation, which requires special attention. The conclusion of this study emphasizes that radiation use must be accompanied by adequate scientific understanding, long-term risk evaluation, and the implementation of strict safety policies to ensure that the benefits of radiation use outweigh the risks.

Persepsi Mahasiswa terhadap Model Pembelajaran Project Based Learning Berbasis Eksperimen dengan Produk Artikel Ilmiah pada Mata Kuliah Botani Tingkat Rendah

2026-02-27T02:09:18+07:00

Student perception is their view and assessment of the experience and learning process in the classroom. This is important to study because the success of a learning model is also determined by how students interpret and respond to its implementation. This study aims to determine student perceptions of the implementation of the Project Based Learning (PjBL) learning model based on experiments with scientific articles as products in lower-level botany courses. This study is a quantitative descriptive study with an ex post facto approach using a survey method. Sampling was carried out using a purposive sampling technique on students of the Biology Education Study Program, Faculty of Teacher Training and Education, Mulawarman University. The data analysis technique used descriptive statistical analysis. The results of the data analysis show that the average result of all observed aspects obtained a percentage value of 84.99% which is included in the "very good" category, so it can be concluded that students of the Biology Education Study Program have a positive perception of the implementation of the Project Based Learning (PjBL) learning model based on experiments with scientific articles as products in lower-level botany courses. Therefore, these findings emphasize that the implementation of this learning model is worthy of being maintained and further developed with improvements, particularly in technical aspects and structured academic mentoring to optimize the quality of the learning process and outcomes.

Resistensi Antibiotik Bakteri Escherichia coli dari Air Sumur di Peternakan Ayam Desa Suranadi, Lombok Barat

2026-03-02T01:27:57+07:00

Antimicrobial Resistance (AMR) has become a global health problem. Escherichia coli bacteria in water can act as a reservoir for the spread of antibiotic resistance. The study aimed to determine the resistance of Escherichia coli isolated from well water in chicken farms to antibiotics. The study design was an observational survey conducted from November to December 2022 at five chicken farms in Suranadi Village, Narmada District, West Lombok Regency. Five well water samples used in the study came from five wells in chicken farms located 10 meters from the chicken coop. 250 ml of well water samples were taken, put into sterile bottles, and then taken to the Health Laboratory Testing and Calibration Center of West Nusa Tenggara Province for isolation of Escherichia coli. Escherichia coli was isolated by planting on Eosin Methylene Blue Agar (EMBA) and identified using gram staining and biochemical tests. Antibiotic susceptibility testing of Escherichia coli was conducted using the disc diffusion method using five antibiotics: Gentamicin, Tetracycline, Amoxycillin, Chloramphenicol, and Ciprofloxacin. This study successfully isolated four Escherichia coli from five well water samples. The susceptibility test results showed that 75% of the Escherichia coli isolates were resistant to Amoxycillin, 50% to Ciprofloxacin, and 25% to Chloramphenicol. The Escherichia coli isolates were still sensitive to Gentamicin and Tetracycline.

Pengaruh Variasi Intensitas Cahaya terhadap Laju Fotosintesis pada Tanaman Caladium melalui Metode Floating Leaf Disk Assay

2025-11-17T18:35:59+07:00

Photosynthesis is the process of converting light energy into chemical energy which is greatly influenced by light intensity and leaf pigment content. This study analyzed the effect of three light intensities (dark, shade, and bright) on the photosynthesis rate of Caladium plants using the Floating Leaf Disk Assay (FLDA) method. This method measures the photosynthesis rate based on the leaf disk floatation time as an indicator of oxygen formation from the water photolysis process. The study was conducted at the Biology Laboratory, Faculty of Teacher Training and Education, Lambung Mangkurat University, using a quasi-experimental design with 3 repetitions. The results showed that bright conditions provided the fastest floatation time, which was an average of 3.8 minutes with bubble production of 18-22 bubbles/minute. Shade conditions showed a moderate response with a floatation time of 8.6 minutes and 7-10 bubbles/minute. In dark conditions, neither floatation nor oxygen production occurred. Caladiums with full green leaves exhibited higher photosynthetic rates (3.5-4.0 minutes) than variegated ones (5.2-6.1 minutes), reflecting differences in chlorophyll content. These findings confirm that the combination of light intensity and leaf pigment content is a major factor in determining photosynthetic efficiency. The research findings are expected to provide a basis for optimal lighting management in ornamental plant cultivation and serve as contextual teaching materials in biology learning.

Pengaruh Model Pembelajaran Guided Inquiry Berbantuan E-LKPD terhadap Kemampuan Berpikir Kritis dan Hasil Belajar Peserta Didik pada Materi Sistem Pernapasan di Kelas XI SMA Negeri 17 Samarinda

2026-03-05T01:35:15+07:00

This research is motivated by the lack of variety of learning models that cause students' critical thinking skills and learning outcomes to be still low. Therefore, the guided inquiry model assisted by E-LKPD is used as an alternative to facilitate the investigation process in a directed manner. This study aims to determine the effect of the guided inquiry learning model assisted by E-LKPD on students' critical thinking skills and learning outcomes in the respiratory system material of grade XI at SMA Negeri 17 Samarinda. This research is a quantitative study with a quasi-experimental type, using a non-equivalent control group design. Data collection techniques used pretest and posttest. The research sample consisted of 25 students per class. The experimental class used the guided inquiry model assisted by E-LKPD, while the control class used the Student Teams Achievement Divisions (STAD) model. The results of the t-test (independent sample t-test) showed sig. (2-tailed) of 0.000 < 0.05 and tcount > ttable, namely 4.448 ˃ 2.010 for critical thinking skills, and 4.903 ˃ 2.010 for student learning outcomes. The results of the study indicate that the guided inquiry learning model assisted by E-LKPD has a significant effect on improving critical thinking skills and student learning outcomes in the respiratory system material.

Kajian Etnobiologi pada Makanan Khas Suku Karo di Kecamatan Sibiru-biru Kabupaten Deli Serdang

2026-01-21T15:08:25+07:00

This study aims to document and analyze the traditional food of the Karo Tribe in the seven-monthly ceremony (Mbesur-mbesuri) in the Karo Tribe community in Sibiru-biru District, Deli Serdang Regency. This study was conducted in two villages, namely Biru-biru Village and Rumah Gerat Village, Sibiru-biru District, Deli Serdang Regency. This type of research is descriptive qualitative and quantitative using emic and etic research approaches. Data collection techniques were carried out by participatory observation, interview techniques, documentation techniques, Focus Group Discussions (FGD), plant identification, and animal identification. The results of the study show that the traditional food of the Karo Tribe contained in the seven-monthly ceremony (Mbesur-mbesuri) consists of seven types of mandatory foods that utilize 19 types of plants belonging to 12 families, and 1 type of animal from the Phasianida family. The dominant plant family used in the traditional food of the seven-monthly ceremony (Mbesur-mbesuri) is Zingiberaceae. The most frequently used part of the plant is the fruit, namely 6 types. In terms of plant habitus, herbs are the most dominant species used in the seven-monthly ceremony (Mbesur-mbesuri), with 13 species.

Gambaran Hasil Pemeriksaan Pewarnaan Diff-Quik pada Swab Mukosa PSK

2026-03-14T09:02:28+07:00

High-risk commercial sex workers (CSWs) are highly susceptible to sexually transmitted infections (STIs), which often manifest in the oral mucosa. Therefore, a rapid, accurate, and affordable oral health screening method at the primary healthcare level is needed to detect cellular changes early. The purpose of this study was to describe the morphology of epithelial cells and the quality of oral mucosal swabs obtained using Diff-Quik staining in CSWs. This study used a descriptive observational study of 20 CSW respondents, with a total of 80 samples taken using the buccal mucosal swab technique and stained using the Diff-Quik method. The results showed that 81.25% of the samples had good staining quality, with clear nuclear and cytoplasmic details. Although the cell morphology was generally normal, pathological findings in the form of cellular damage (vacuolization and pyknosis) and inflammatory cell infiltration (PMN leukocytes) were found in 27.5% of the samples. The conclusion of this study is that Diff-Quick staining is very effective for rapidly assessing oral cytology, which indicates inflammation and cell damage in CSWs in the region.

Pengaruh Konsentrasi Ekstrak Bawang Merah (Allium cepa L.) sebagai Zat Pengatur Tumbuh terhadap Pertumbuhan Krisan (Chrysanthemum morifolium) Secara In Vitro

2026-03-14T23:06:19+07:00

Chrysanthemum (Chrysanthemum morifolium) is a major ornamental plant commodity in Indonesia with a production level of up to 459 million stems. The success of in vitro propagation is largely determined by the use of appropriate Plant Growth Regulators (PGRs). This study aimed to evaluate the performance of shallot (Allium cepa L.) extract as a natural PGR, while determining the optimal dose to support chrysanthemum growth in vitro. The study was conducted at the Laboratory of the Horticulture Main Center (BIH) Gedung Johor, Medan, from October 2025 to January 2026, using a Completely Randomized Design (CRD) that included six concentration levels (K0=0; K1=5; K2=10; K3=15; K4=20; and K5=25 mL L⁻¹), with 10 replications. Data analysis was performed using ANOVA-DMRT for parametric data and Kruskal-Wallis–Dunn for non-parametric data. The study results indicated a significant effect (p < 0.01) on all growth parameters. A concentration of 20 mL L⁻¹ was most effective for organogenesis, producing 15.60 leaves, 7.85 roots, and 3.15 shoots; while 5 mL L⁻¹ was superior for elongation, with plantlets reaching 8.99 cm in height. Concentrations above the optimal dose actually inhibited growth due to the accumulation of phytotoxic compounds. These findings provide a more cost-effective and sustainable chrysanthemum propagation protocol as a substitute for synthetic plant growth regulators.

Analisis Tingkat Pemahaman Siswa pada Materi Perubahan dan Pelestarian Lingkungan di Kelas X SMA Negeri 1 Tilango

2026-03-09T22:49:46+07:00

This study aims to analyze the level of student understanding of environmental change and conservation in grade X of SMA Negeri 1 Tilango. The study used a descriptive quantitative approach, involving 25 grade X3 students. The method used was a multiple-choice test based on seven indicators of understanding: identifying, explaining, interpreting, classifying, comparing, summarizing, and understanding. The results showed that all indicators improved from the pretest, which was generally in the low category, to the posttest, which reached an average of 77.81%, categorized as high. This improvement reflects that the applied learning process was able to improve students' conceptual mastery of environmental change and conservation, while simultaneously strengthening their analytical thinking skills. A comparison of pretest and posttest scores indicates that the instrument used was effective in measuring students' conceptual understanding and that the applied learning positively influenced learning outcomes.