Ethnobotany in a Modern City: The Persistence in the Use of Medicinal Plants in Guadalajara, Mexico
Related Concept Videos
Plants often form mutualistic relationships with soil-dwelling fungi or bacteria to enhance their roots’ nutrient uptake ability. Root-colonizing fungi (e.g., mycorrhizae) increase a plant’s root surface area, which promotes nutrient absorption. While root-colonizing, nitrogen-fixing bacteria (e.g., rhizobia) convert atmospheric nitrogen (N2) into ammonia (NH3), making nitrogen available to plants for various biological functions. For example, nitrogen is essential for the...
Human civilization relies on biodiversity in many ways. Sudden changes in species biodiversity result in environmental changes that can modify weather patterns and therefore human civilizations.
Humans are dependent on agriculture, which developed when ancestral humans found species that made suitable foods. At least 11,000 years ago, humans started to select plant and animal species to be cultivated on farms. Going back for thousands of years, humans have been artificially selecting species...
From Water to Land
Kingdom Plantae first appeared about 410 million years ago as green algae transitioned from water to land. This land was a relatively uncolonized environment with ample resources. Terrestrial environments also offered more light and carbon dioxide, required by plants to grow and survive.
However, the stark differences between land and sea posed a formidable challenge to early colonizing species prompting many new adaptations that have resulted in the wide variety of plant...
Plant hormones—or phytohormones—are chemical molecules that modulate one or more physiological processes of a plant. In animals, hormones are often produced in specific glands and circulated via the circulatory system. However, plants lack hormone-producing glands.
Instead, plant hormones are often produced in regions of active growth, like the tips of roots and shoots. Additionally, even very low concentrations of plant hormones can have a profound effect on growth and development...
Gaseous substances like general anesthetics are absorbed and excreted through the lungs via simple diffusion. This process depends on factors such as pulmonary blood flow, respiration rate, and the substance's solubility. Gaseous anesthetics like nitrous oxide with low blood solubility are excreted rapidly, while compounds like alcohol, with high blood and tissue solubility, are excreted slowly.
Drugs can also be excreted in breast milk, which is crucial for breastfeeding infants. The...
Crop cultivation has a long history in human civilization, with records showing the cultivation of cereal plants beginning at around 8000 BC. This early plant breeding was developed primarily to provide a steady supply of food.
As humans' understanding of genetics advanced, improved crop varieties could be achieved more quickly. Artificial selection could be more directed, and crop varieties enhanced for favorable traits more quickly to produce better, more robust, or more palatable...

