Botany
Botany studies plants as integrated living systems. Follow water and nutrients from roots, carbon through leaves, transported resources between source and sink tissues, growth from meristems, reproduction across life cycles, and the ecological and evolutionary conditions that shape plant form.
A leaf cannot open itself to carbon dioxide without also opening itself to the atmosphere.
Start with a physiological tradeoff instead of a specimen gallery. Once gas exchange is visible, photosynthesis, water transport, stomatal regulation, and whole-plant allocation have somewhere concrete to attach.
Opening a pore helps CO₂ enter, but it also opens a path for water vapor to leave.
Change stomatal aperture and outside-air dryness. The outputs are normalized diffusion-capacity indicators, not measured photosynthesis or transpiration rates for a real species.
A wider modeled pore increases both diffusion pathways. Outside humidity changes the water-loss side without changing the aperture itself.
normalized aperture-dependent indicator
normalized aperture × dryness indicator
Plants connect soil, atmosphere, and growing tissues through moving gradients and source–sink relationships.
The arrows below are a reading order, not four isolated departments. Root uptake changes leaf water status; stomata change transpiration; carbon fixation changes sugar supply; sinks feed back on where resources are allocated.
Root interface
What enters from soil and what limits uptake?Roots interact with water, dissolved ions, soil structure, microbes, oxygen availability, and mycorrhizal partners. Uptake is selective and physiologically regulated.
Xylem
How can water move from roots toward leaves?Xylem transports water and dissolved minerals through dead conducting cells in many vascular plants. Transpiration, cohesion, pressure, anatomy, and soil–plant–air gradients all matter.
Leaf exchange
How does a leaf acquire CO₂ without losing unlimited water?Stomata regulate a diffusion pathway between internal leaf air spaces and the atmosphere. Photosynthetic carbon gain and water loss are coupled to a larger control system.
Phloem & sinks
Where do sugars and other transported compounds go?Phloem moves products from source tissues toward sinks such as growing organs, roots, fruits, storage tissues, or other demanding regions. Source–sink direction can change with development and season.
No single process explains a plant.
Botany moves between cell-scale mechanisms, tissue architecture, whole-organism allocation, life cycles, populations, and ecosystems. The same trait can be understood differently at each scale.