Students take a close look at the math & biology involved in the creation of seed, leaf, and petal spiral patterns. These multi-modal, inquiry-oriented activities align with NGSS and CCSS and are scalable for middle and high school/AP students.
In this investigation, students explore how various amounts of fertilizer affect growth and development of plants.
Source: Wisconsin Fasts Plants
Students use barley, radish or algae to explore how various macronutrients and micronutrients affect growth.
View resource from the Nuffield Foundation
Candy in classrooms seems inevitable at certain times of the year. This simple handout offers a little food for thought so students can learn a few yummy morsels about the plants they are enjoying in every delicious bite.
Note: The visuals are kid-friendly but some key vocabulary is not; primary students may need guidance.
Explore the verdant garden of words and phrases rooted in plants through science-oriented word play suitable for sophisticated middle schoolers & up.
Farming mutualisms, in which an organism benefits from another to promote growth, have evolved in many lineages. In particular, symbioses between plants and ants are mostly defensive mutualisms. In this paper, Chomicki and Renner describe the obligate mutualism observed between epiphytes in the genus Squamellaria and Philidris nagasau ants. They observed that P. nagasau ants disperse Squamellaria seeds inhabited by these specialist ants, and take care of the seedlings by fertilizing them actively, showing evidence for the first instance of obligate farming of plants by ants. Furthermore, they show that some traits of these plants and their specialist ants have coevolved around 3 million years. (Summary by Gaby Auge) Nature Plants, doi:10.1038/nplants.2016.181
Pitcher plants are carnivorous, similar to Venus fly traps. However, pitcher plants have fluid-filled modified leaves instead of the movable lobes found on Venus fly traps. The pitcher plant’s modified leaf contains bacteria-laden water that traps small insects, but how are the insects trapped in the fluid? Armitage found the bacteria lower the surface tension of the pitcher plant’s fluid to trap prey by drowning. The author made artificial pitcher plant fluid, which had similar physical properties to natural pitcher plant fluid. Both natural and artificial pitcher plant fluids had interfacial tension lower than pure water. The genera of common bacteria in pitcher plant fluid, including Pseudomonas and Pedobacter, have been determined. However, the biological mechanism for how these bacteria lower the surface tension of pitcher plant fluid remains unknown; perhaps these bacteria secrete surfactants that lower surface tension. (Review by Daniel Czerny) Biol. Lett. 10.1098/rsbl.2016.0577
HAK5 is a high-affinity potassium transporter that is transcriptionally repressed in high K+ conditions. Zhao et al. identified hormone-related cis-elements in the HAK5 promoter. They screened mutants deficient in transcription factors associated with these cis-elements and found that arf2 mutants show enhanced K+ uptake and root growth on low-K medium, whereas ARF2 overexpression lines showed decreased K+ uptake, indicating that ARF2 acts as a transcriptional repressor. The authors further showed that under low K conditions, ARF2 is phosphorylated, relieving its repressive function. Plant Cell 10.1105/tpc.16.00684
Questions remain about the evolutionary origins and functions of stomata. They are absent from liverworts, present to a limited extent in mosses, and are found on 410 million year-old fossils of Cooksonia, a leafless plant. Chater et al. show that orthologs of two key transcription factors that control guard cell development in Arabidopsis are expressed and required for guard cell development in the moss Physcomitrellis patens. The genes are expressed in the sporophyte but not the photosynthetic gametophyte, raising questions about stomatal function. Knocking out either gene leads to the delayed dehiscence of spore capsules, suggesting that reproduction was stomatas’ ancestral function. Nature Plants 10.1038/nplants.2016.179