Developmental Biology - Root and Shoot Growth

This free online biology course introduces you to the creation and development of the root and shoot systems in plants. We lay out the major steps taken during root development and explain how the establishment of the root apical meristem is dependent on the specification of a stem cell niche and the subsequent development of the quiescent centre at the presumptive root pole. We break down the regulation of the transcription factors involved in root growth and stem cell maintenance. We establish how asymmetric cell division produces two ‘daughter’ cells with different cellular fates and how the cortex’s endodermis initial cell generates two ground tissues. This includes the role of transcription factors in contributing to the sequential development of vascular tissues. We investigate how the xylem and phloem tissues occur together in vascular bundles in each organ of the plant and examine the role of vascular tissues in facilitating the transportation of water, minerals and food throughout the plant.

The course then breaks down the concept of ‘root branching’ and analyzes lateral root development. We demonstrate how auxin signalling regulates lateral root development through the transcriptional regulation of the key components involved in the developmental process. We then show you how the shoot apical meristem generates above-ground aerial organs throughout the life of higher plants. The course highlights how organogenesis is the result of organ formation through dedifferentiation of differentiated cells and reorganization of cell division to create a particular organ. We demonstrate the process of deriving the lateral organs of the plants from the flanks of apical meristems and their inherent positional relationship. We then investigate how leaves grow by distinct phases that are controlled by the gene regulatory networks and affected by many transcription factors. 

Finally, we lay out the developmental change in a plant's life cycle that is marked by the floral transition. The course establishes how a photoreceptor may regulate flowering time in response to different photoperiods through its regulation of the circadian clock. We identify various types of genes that participate in the specification of floral organ identity. The course outlines how plant cells communicate to coordinate their activities in response to changing light and temperature conditions that guide their growth cycle. We also explain how plasmodesmata connect cells to form a communication network within plants. The course unpacks such concepts and teaches you basic botanical lab techniques. We investigate the biological and physical methods used to transform explants into regenerated calluses. This informative course suits anyone interested in plant sciences, botany, biotechnology or agriculture. It can help students find their path forward or refresh the knowledge of seasoned professionals.