The Research Of Learning Progression On Improtant Ideas In High School Biology

In the past decade or so,research on learning progression has become a hot topic in the field of international science education.The main purpose of research and learning is to maintain the consistency of grades and grades in three aspects of curriculum standards,curriculum content and curriculum evaluation,changing the current status of fragmented learning and lack of convergence.In order to enable students to grasp concepts more clearly and build a scientific knowledge framework to improve students’ ability to apply knowledge to life to solve practical problems,the construction of the important ideas of the learning progression is of great significance to the convergence of the curriculum,students’ learning,teachers’ teaching and examination evaluation.This study took the topic of “the relationship between genes and chromosomes” in the biology of high schools in China as an example.By combing and summarizing the China PEP high school biology textbooks,a total of four important ideas were identified: meiosis,fertilization,genes on chromosomes,and genetic inheritance.Then analyze and compare Chinese and American Curriculum Standards,and sum up the different levels of expected goals of the four important ideas.According to these goals,the important ideas test questions for the topic “The relationship between genes and chromosomes” were developed.A total of288 students from three different levels of schools in Sichuan,Chongqing and prefectures were selected as the research objects,using the developed important ideas test questions as research tools,statistical analysis of the correctness and concentration of each topic,and then positioning to a specific advanced position,and ultimately determine the advanced level of the target corresponding to the topic.The conclusions are as follows:1 An learning progression description of the ideas of "meiosis"Level 1: Elucidating meiosis produces sperm cells or egg cells that contain only half of the genetic information.Level 2: Elucidating the free combination and cross-interchange ofchromosomes during the process of meiosis in the organisms that carry out sexual reproduction,will lead to the recombination of genes that control different traits,so that the offspring will mutate.Level 3: Development and use of models to describe why the genetic information of offspring that have been clonally propagated has exactly the same genetic information and the genetic information of sexually propagated offspring will mutate.Level 4:Elucidate the process of meiosis of cells and simulate changes in chromosomes during division.2 The learning progression expression of the ideas of "fertilization"Level 1: It is known that fertilized eggs are formed by the combination of egg cells and sperm.Level 2: An organism that reproduces sexual reproduction,whose genetic information is transmitted to offspring through gametes.Level 3: Give an example of the formation process of fertilized eggs.Level 4: Develop and use models to illustrate the fertilization process.3 The learning progression expression of the ideas “genes on chromosomes”Level 1: Demonstrate that DNA is the main genetic material.Level 2: An example shows that the trait of the organism is controlled by the gene.Level 3: Describe the relationship between chromosomes,DNA,and genes.Level 4: Development and use of models to describe why changes in the structure of the gene located on the chromosome affect the protein,thereby affecting the structure and function of the organism.4 The learning progression expression of the ideas of "association of inheritance"Level 1: Explain the person’s gender decision.Level 2: Outline gene transfer and sex on sex chromosomes.Level 3: Overview of sexual genetics.Level 4: Apply statistics and probabilities to explain the variation and distribution of gene expression in the population.