Accuracy and Idea Consideration: A Study of Small-Group Interaction in Biology.

Small-group discussion is a central component of 21st-century biology classrooms. Many factors shape these discussions and thus influence potential learning gains. This study examined how accuracy and idea consideration shaped small-group discussions in undergraduate biology labs (12 groups, M = 42.8 talk turns). To do this, we asked 1) Is there a relationship between a student's science accuracy and the amount peers consider the student's ideas? 2) To what extent does peer consideration of a student's ideas predict that student's ability to steer the conversation? Building on this second question, we then explored 3) Does general group academic ability or immediate conversational accuracy better predict group learning? To answer these questions, we coded aspects of discourse (science accuracy, idea consideration, etc.) before quantitative analysis. Strong correlation was found between students' science accuracy and idea consideration (r = 0.70). Both accuracy and idea building predicted one's ability to steer the conversation. Subsequent analysis highlighted the critical role of immediate discourse in group learning. Group-level analysis revealed that group performance was not related to the group's overall ability in the classroom, but rather the immediate accuracy of their group conversations. Implications and limitations are discussed.

Genetics and Physiology of the Nuclearly Inherited Yellow Foliar Mutants in Soybean.

Plant photosynthetic pigments are important in harvesting the light energy and transfer of energy during photosynthesis. There are several yellow foliar mutants discovered in soybean and chromosomal locations for about half of them have been deduced. Viable-yellow mutants are capable of surviving with decreased photosynthesis, while lethal-yellow mutants die shortly after germination. In addition to the decreased chlorophyll content, other features associated with yellow mutants include altered Chl a and Chl b ratio, reduction in chloroplast size and number, lower levels of other photosynthetic pigments, inability of thylakoids to stack into granum, lack of lamellae to interconnect granum and reduced size of the light harvesting complex. For some yellow mutants, temperature and/or light play a critical role in the manifestation of phenotype. Although yellow foliar mutants are viewed as undesirable for crop production, there is the possibility of these mutants to create a positive impact by reducing the total amount of chlorophyll and diverting resources toward increased biochemical photosynthetic capacity leading to increased yield. Recent advances in model plants led to the isolation and characterization of various genes associated with yellow foliar phenotype. Knowledge gained from the model plants can be applied using homology based cloning approach to isolate genes in soybean and understanding the modes of actions of the involved proteins. Identifying and characterizing yellow foliar mutants will not only aid in understanding the biosynthetic pathways involved in the photosynthetic machinery, but may also provide ways to increase soybean productivity.