Research On Probing And Changing Students' Prescientific Conceptions Of Cellular Knowledge In Grade Seven

In the Compulsory Education Biology Curriculum Standard(2011 Edition),improving the scientific literacy is still one of the important contents of the basic concept of curriculum,and the scientific concept is the important foundation of cultivating scientific literacy.Therefore,to carry out scientific education,it is necessary to put the scientific concept into the focus of education,which is one of the keys to the cultivation of students' scientific literacy.The students' knowledge and concepts in life experience and previous studies are generally referred to as prescientific conceptions.Therefore,it is the core of the concept teaching to probe into the students' prescientific conceptions and study the law of their changes.This study took the prescientific conceptions of basic knowledge of biological cells in grade seven as the main research content.Firstly,this thesis collected and sorted out the relevant literature about the prescientific conceptions and the conceptual change by the literature method.Secondly,I used the two—tier diagnostic assessment to explore the precientific conceptions of grade seven students' basic knowledge about cell.Analyzed the results of the investigation and summarized the students' prescientific conceptions of cell knowledge.The analysis results showed that:in respect of plant and animal cell temporary slide making experiments,students had many prescientific conceptions for experimental operations,but they know little about the name of the experimental appliance and the role of reagents.In the basic knowledge of animal and plant cells,students had a good understanding of cell wall,cell membrane,cell nucleus and chloroplast,and they had different levels of precientific conceptions for their structure and function.But students were not clear about the concept of "cell" and "cell structure" and didn't know where each cell structure is located in the whole cell,it is difficult for students to relate the characteristics of cell life activities to the corresponding cellular structures.At last,according to the survey results,chosen the corresponding lessons to practice teaching for conceptual change,and through the class of spot test,tested the conceptual change teaching effect.Test results were analyzed by difference examination,and it obtained(P)<0.05.The results showed that applied the teaching method based on the theory of the conceptual change of teaching at home and abroad to the teaching practice,the teaching effect was obviously better than the untargeted teaching mode.