The living dead: transformative experiences in modelling natural selection

This study considers how students change their coherent conceptual understanding of natural selection through a hands-on simulation. The results show that most students change their understanding. In addition, some students also underwent a transformative experience and used their new knowledge in a leisure time activity. These transformative experiences appear in different categories where students find value both towards biological content, societal value and individual identity. Finally there is a discussion on how to transfer characteristics from the setting of this study to other educational settings in biology and science in general.     

Connecting ecology to daily life: how students and teachers relate food webs to the food they eat

This study used sociocultural learning theory to better understand how middle and high school environmental science and biology students and pre- and in-service science teachers connect the daily life activity of eating to the food web model learned in school. We sought to understand how student and teacher perceptions of the environment and their experiences influenced their responses to interview questions regarding this topic. Findings, based on transcribed interviews with 54 study participants, indicate that three quarters of teachers and students were unable to connect the food they eat with ecosystem food webs. Even so, many respondents particularly those from elite public schools, did not demonstrate common food web misconceptions identified by other researchers, instead showing a sophisticated understanding of food web interactions. These findings indicate that even though participants were proficient in their school science understanding of food web interactions, they did not readily think about how their everyday out of school activities, like eating, relate to those interactions. This may be representative of a more general disconnect between formal ecology instruction and daily life activities. We provide several recommendations for how this disconnect can be remedied in our classrooms.     

A study of absorption of energy of the extremely high frequency electromagnetic radiation in the rat skin by various dosimetric methods and approaches

Using experimental and theoretical methods of dosimetry, the energy absorption of extremely high-frequency electromagnetic radiation (EHF EMR) in the skin of laboratory rats was analyzed. Specific absorption rate (SAR) in the skin was determined on the basis of both microthermometric measurements of initial rates of temperature rise in rat skin induced by the exposure and microcalorimetric measurements of specific heat of the skin. Theoretical calculations of SAR in the skin were performed with consideration for dielectric parameters of rat skin obtained from the measurements of the standing wave ratio upon reflection of electromagnetic waves from the skin surface and for the effective area of stationary overheating measured by infrared thermography. A numerical method was developed to determine electromagnetic wave energy reflected, absorbed, and transmitted in the model of flat layers. The algorithm of the method was realized in a computer program and used to calculate SAR in the skin on the basis of the complex dielectric constant of rat skin. The SAR values obtained from experimental measurements, theoretical calculations and numerical analysis are in good mutual correspondence and make about 220-280 W/kg at a frequency of 42.25 GHz and a power of 20 mW at the radiator output. The results obtained can be used for dosimetric supply of biomedical experiments on studying the physicochemical mechanisms of the biological effects of EHF EMR.     

Effect of low intensity pulse-modulated electromagnetic radiation on activity of alkaline phosphatase in blood serum

The change in alkaline phosphotase activity in vitro with frequencies modulation at low intensity of pulse-modulated electromagnetic radiation was experimentally shown (EMR, 2375 MHz, intensity: 0.8, 8.0; 40.0 microW/cm2; range modulation: 30-310 Hz; time of interaction: 1-3 min). Revealed effects could be regarded as an evidence of informative character of interaction of modulated EMR.     

Modifications of Motor Asymmetry in Rats under the Influence of Low-Intensity Extra High-Frequency Electromagnetic Radiation in the Norm and under Stress Conditions

We studied modifications of motor asymmetry in rats with different motor lateralization (dextrals, sinistrals, and ambidextrals) induced by low-intensity extra high-frequency (EHF) electromagnetic radiation (EMR), hypokinetic stress, and their combination. It was found that the development of hypokinetic stress in rats induced by limitation of their mobility results in a considerable decrease of the coefficient of motor asymmetry (up to inversion of its sign); this can be related to a decrease in the resistivity to stressing and adaptability of the organism to the influence of external factors. The influence of EHF EMR on the animals under conditions of both normal and limited motor activity resulted in an increase in the index of motor lateralization in animals of all phenotypic groups under study; probably, this helped to increase the adaptive capabilities of the organism. Neirofiziologiya/Neurophysiology, Vol. 37, No. 2, pp. 164–168, March–April, 2005.     

Science Classroom Inquiry (SCI) Simulations: A Novel Method to Scaffold Science Learning

Science education is progressively more focused on employing inquiry-based learning methods in the classroom and increasing scientific literacy among students. However, due to time and resource constraints, many classroom science activities and laboratory experiments focus on simple inquiry, with a step-by-step approach to reach predetermined outcomes. The science classroom inquiry (SCI) simulations were designed to give students real life, authentic science experiences within the confines of a typical classroom. The SCI simulations allow students to engage with a science problem in a meaningful, inquiry-based manner. Three discrete SCI simulations were created as website applications for use with middle school and high school students. For each simulation, students were tasked with solving a scientific problem through investigation and hypothesis testing. After completion of the simulation, 67% of students reported a change in how they perceived authentic science practices, specifically related to the complex and dynamic nature of scientific research and how scientists approach problems. Moreover, 80% of the students who did not report a change in how they viewed the practice of science indicated that the simulation confirmed or strengthened their prior understanding. Additionally, we found a statistically significant positive correlation between students’ self-reported changes in understanding of authentic science practices and the degree to which each simulation benefitted learning. Since SCI simulations were effective in promoting both student learning and student understanding of authentic science practices with both middle and high school students, we propose that SCI simulations are a valuable and versatile technology that can be used to educate and inspire a wide range of science students on the real-world complexities inherent in scientific study.     

Inquiring into Familiar Objects: An Inquiry-Based Approach to Introduce Scientific Vocabulary

Learning science vocabulary is an often tedious but important component of many curricula. Frequently, students are expected to learn science vocabulary indirectly, but this method can hinder the success of lower-performing students (Carlisle, Fleming, and Gudbrandsen 2000). We have developed an inquiry-based vocabulary activity wherein students explore how new words apply to familiar objects, piquing their interest in the words’ meanings, prior to direct instruction. Groups of students were asked to apply new vocabulary words to familiar objects set up at various rotation stations. The students were encouraged to play with the objects, discuss answers with their group, and write down the vocabulary words they thought best described each object. Since the words were new to the students, there was no credit for correct answers, making the students comfortable exploring a new topic. After the rotation stations, we led students in a discussion of their answers and followed up with direct instruction on the words’ definitions. Here we give three examples of this activity used in our physical science classroom—one each for energy, simple machines, and force vocabulary—but this activity can easily be modified for biology and Earth science curricula.     

Race to the Future: Integrating 21st Century Skills into Science Instruction

Race to the Future is an exciting and dynamic activity modeled after the reality television show The Amazing Race. It exemplifies how 21st century skills can be incorporated into core subject instruction and at the same time positively enhance student engagement. In this activity, students work quickly and cooperatively with their teammates and use 21st century skills to successfully decipher five clues related to science content. We have used this activity with excellent results with different groups of students (middle school, high school, and university students), for different purposes (ice-breaker, team-building, course assessment, and evaluation), and in broad curriculum areas (science and math). However, the activity is especially powerful when introduced during the first day or week of class. The meaningful and enjoyable student collaboration, the upbeat class environment, and the enhanced student engagement achieved at the conclusion of this challenging activity set an optimal teaching and learning environment for the entire quarter/semester.     

EvoS: A Prescription for What Ails Pre-Medical Education?

Pre-medical students are certainly a widely varied group, with different motivations and experiences, different skills sets and interests. However, they often tend to approach their undergraduate education as a necessary evil that they must endure in order to achieve their ultimate goals. This article summarizes recent literature addressing some of the questions that have been raised regarding pre-medical education programs. Are students prepared for the intellectual, emotional, and even physical challenges of medical training? What deficiencies are commonly seen in entering medical students? What are students’ perceptions of how well their pre-medical studies helped them? Many of these studies have resulted in a call for more science training, while some have advocated for less, but with an enhanced focus on humanistic studies. We supply a brief outline of our Evolutionary Studies (EvoS) program and reflect upon how participation in this program can enhance pre-medical students’ education. Importantly, we argue that EvoS can expand students’ depth of understanding of science, as well as nurture their ability to think about the needs of their patients and the context of their medical practice.     

Gregor Mendel's classic paper and the nature of science in genetics courses

The discoveries of Gregor Mendel, as described by Mendel in his 1866 paper Versuche uber Pflanzen-Hybriden (Experiments on plant hybrids), can be used in undergraduate genetics and biology courses to engage students about specific nature of science characteristics and their relationship to four of his major contributions to genetics. The use of primary source literature as an instructional tool to enhance genetics students' understanding of the nature of science helps students more clearly understand how scientists work and how the science of genetics has evolved as a discipline. We offer a historical background of how the nature of science developed as a concept and show how Mendel's investigations of heredity can enrich biology and genetics courses by exemplifying the nature of science.     

Observing Rocks in the Elementary Grades…

The ocean is a major influence on weather and climate. With this set of lessons, middle school Earth systems science teachers can help their students build an understanding of how large bodies of water can serve as a heat source or sink at different times and how proximity to water moderates climate along the coast. The activity's combination of laboratory investigation, map study, and graphing applies different learning styles and provides practice in important science processes. The activities are adapted from Earth Systems Education Activities for Great Lakes Schools: Great Lakes Climate and Water Movement (V. J. Mayer et al. 1996).     

Gaming as a Platform for Developing Science Practices

Gaming, an integral part of many students’ lives outside school, can provide an engaging platform for focusing students on important disciplinary core concepts as an entry into developing students’ understanding of these concepts through science practices. This article highlights how S’cape can be used to support student learning aligned with the most recent standards documents. Through combining students’ initial engagement in a motivating gaming experience with a two-experiment scaffolded inquiry sequence enhanced with information literacy-targeted homework, this article reveals how support can be offered for asking questions, planning and carrying out investigations, analyzing and interpreting data, constructing explanations, and engaging in argument from evidence to refine understandings of core concepts. We believe that as science teachers strive to explore important concepts with students through allowing them to actually practice science, games such as S’cape strategically leveraged and sequenced with scaffolded inquiry experiences can support these efforts.     

Sterilization the Sane “Pesticide”

Unpacking, an effective lesson-planning technique, can help students use scientific inquiry to understand the power behind hurricanes. Teachers identify a concept and then guide students to "unpack" it and look for new discoveries. The activity provides a means for students to develop the abilities to do scientific inquiry, demonstrate how it is applied, and develop understanding about the method. Additionally, students demonstrate abilities of technological design and understanding about science and technology. This activity promotes students' knowledge of the Earth's constant change, pattern recognition to enable prediction, statistical analysis and graphical display to reveal patterns in data, and the science behind hurricane rotation.     

Lack of Evolution Acceptance Inhibits Students’ Negotiation of Biology-based Socioscientific Issues

The purpose of this study was to explore science content used during college students’ negotiation of biology-based socioscientific issues (SSI) and examine how it related to students’ conceptual understanding and acceptance of biological evolution. The Socioscientific Issues Questionnaire (SSI-Q) was developed to measure depth of evolutionary science content use during SSI negotiation. Fifty-two upper level undergraduate biology and non-biology majors completed the SSI-Q and also the Conceptual Inventory of Natural Selection to assess evolution understanding and the Measure of Acceptance of the Theory of Evolution to appraise evolution acceptance. A multiple regression analysis tested for interaction effects between the predictor variables, evolution understanding and evolution acceptance. Results indicate that college students primarily use science concepts related to evolution to negotiate biology-based SSI including variation in a population, inheritance of traits, differential success, and change through time. The hypothesis that the extent of one’s acceptance of evolution is a mitigating factor in how science content related to evolution is evoked during SSI negotiation was supported by the data, in that such content was consistently evoked by participants for each of the three SSI scenarios used in this study.     

Enhancing Elementary Students’ Experiences Learning about Circuits Using an Exploration–Explanation Instructional Sequence

Using an exploration–explanation sequence of science instruction helps teachers unveil students’ prior knowledge about circuits and engage them in minds-on science learning. In these lessons, fourth grade students make predictions and test their ideas about circuits in series through hands-on investigations. The teacher helps students make connections between their hands-on experiences collecting data and new terms. This lesson shows how teachers can incorporate formative assessments such as checkpoints, self tests, and exit slips into the explanation phase of instruction so students can evaluate and self-monitor their understanding of circuits in series. These activities meet the National Science Education Standards for active, student-center learning environments that cultivate the critical thinking skills necessary to learn science.     

Local Tree Mapping: A Collaborative,Place-Based Activity Integrating Science,Technology, Math,and Geography

This inquiry-based activity designed for the fifth through 12th grade allows students to engage in an outdoor, place-based experience, working collaboratively both in groups and as a class to accomplish the class goal of creating a local tree map linked to student-collected data about each tree. During Local Tree Mapping, students explore the local trees in the yard or neighborhood of the school, while learning basic skills in geographical information systems and Microsoft Excel. Through this activity, students gain a deeper understanding of and appreciation for the role of trees within the Earth's ecosystems, as they collect data on tree type, height, diameter, age, and the longitude and latitude of the trees. An extension activity is described in which students can enter their tree data into a carbon dioxide (CO₂) emissions reduction calculator to determine how much CO₂ is sequestered by the trees in their research site. Local Tree Mapping provides an opportunity for students to gain inquiry skills in science, mathematics, and geography as they participate firsthand in the collection, analysis, and presentation of real-world data that can be utilized by the local community.     

Interhemisphere Asymmetry of the Pro-/Antioxidant Systems in the Rat Brain: Effects of Hypokinesia and Extrahigh-Frequency Electromagnetic Radiation

We studied changes in the interhemisphere asymmetry of the intensity of lipid peroxidation (LPO) and total content of thiol groups (TTG) in the rat cerebral neocortex. These indices characteristic for animals with different motor phenotypes (dextrals, sinistrals, and ambidextrals) were measured in the control and under the influence of hypokinesia, low-intensity millimeter-range electromagnetic radiation (mmR EMR), and their combination. The development of hypokinetic stress in rats (after 10-day-long motor restriction) resulted in a sharp activation of LPO and suppression of thiol/disulfide metabolism in the neocortex of rats with different types of motor asymmetry. Hypokinesia was accompanied by considerable drops in the coefficients of interhemisphere asymmetry (up to reversal of their signs); this can be related to decreases in the resistivity of the organism to stress and adaptability to external influences. When intact animals with different types of motor asymmetry were irradiated with mmR EMR, the intensity of LPO in the neocortex of both hemispheres decreased concurrently with intensification of thiol/ disulfide metabolism. The combined influence of hypokinesia and mmR EMR led to considerably smaller shifts in the above indices, as compared with those after isolated action of hypokinesia. When mmR EMR influenced animals were kept under conditions of normal motor mode and motor restriction, the signs of the coefficients of asymmetry of the indices under study did not change, while the intensity of interhemisphere asymmetry increased. We suppose that this is related to an increase in the adaptability of the organism to the action of stressor factors.     

The Heat Is On! Using Particle Models to Change Students' Conceptions of Heat and Temperature

Elementary, middle-level, and high school science teachers commonly find their students have misconceptions about heat and temperature. Unfortunately, student misconceptions are difficult to modify or change and can prevent students from learning the accurate scientific explanation. In order to improve our students' understanding of heat and temperature, we created a three-part instructional activity designed to engage them in the development of kinetic particle models. First, the students use household materials—food coloring and water—to investigate and create particle models depicting motion at the molecular level. Second, the students complete a similar activity designed to help them visualize the connections between heat and particle motion. Third, the students build a thermometer, observe it in action, and create particle models explaining how the thermometer works. By the end of the series of activities, the students are able develop their own definitions for heat and temperature. Through this hands-on and minds-on series of activities, students learn to define and differentiate the concepts of heat and temperature.     

Identification and quantification of three active auxins in different tissues of Tropaeolum majus

Indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and phenylacetic acid (PAA) were identified as endogenous compounds with auxin activity in nasturtium ( Tropaeolum majus L.) by full scan gas chromatography-mass spectrometry. The endogenous concentrations of the three auxins were measured by GC-selected ion monitoring-MS and isotope dilution analysis using stable labelled isotopes. PAA was present at concentrations about 10- to 100-fold lower than IAA, whereas IBA was found to be in the same concentration range as IAA. Free IAA was highest in roots followed by young leaves. IBA was also highest in the roots, and relatively high concentrations were found in young leaves and flowers. The distribution of PAA was quite different from that found for IBA. No PAA could be detected in young leaves and flowers, and in all other tissues studied the concentrations were well below those of the other two auxin compounds. The presence of a nitrilase gene family and nitrilase activity in extracts from T. majus suggests that PAA might be synthesized by the nitrilase pathway using benzylglucosinolate as precursor.     

How Thin Is Foil? Applying Density to Find the Thickness of Aluminum Foil

In this activity, I show how high school students apply their knowledge of density to solve an unknown variable, such as thickness. Students leave this activity with a better understanding of density, the knowledge that density is a characteristic property of a given substance, and the ways density can be measured.