Five Key Lessons

Photo of a plant leaf.

Plant Biology 40: The (Secret) Life of Plants

To human eyes, plants seem largely inactive. And yet, rooted to the soil in which they germinated, they silently perform a dazzling chemical reaction, using sunlight to make food. Without this photosynthesis, none of the food that humans consume would exist. Taught by Professor Patricia Zambryski, a molecular and cellular biologist, this course explains the fundamental scientific principles of botany to non-science majors. A few takeaways:

  1. Eat the sun! Photosynthesis, the chemical reaction through which plants use sunlight to synthesize foods from carbon dioxide and water, is a key component to supporting life on Earth.

  2. Plants survived massive global extinctions. There are many reasons: Plants’ adaptations make them extremely resilient. They create their own food and can regrow when their limbs are chopped off. Often they carry extra copies of chromosomes, and they can make “clones” of themselves. Seeds can even carry embryos in a dormant state for hundreds of years or travel to distant favorable locations around the globe.

  3. Plant-gene editing: nature did it first. Agrobacterium—a bacterium known for its ability to modify plant DNA—was the original gene- editing tool. It is still used by researchers, even as CRISPR and other biotechnological approaches rapidly change the field of genetic engineering.

  4. Flowers live luscious lives. As plants’ sex organs, flowers make gametes and seeds and are responsible for fruits and many vegetables: a fruit is usually just the ripened, seed-filled ovary or ovaries from one or more flowers. Fruit provides the mechanism for seed dispersal, with many animal species consuming plant parts and spreading them after digestion.

  5. New frontiers of food and fuel. Emerging markets for biofuels and plant-based protein have the potential to help solve some of the problems brought on by climate change. It’s the Wild West for food and energy solutions!