Lecture Notes: Plant Growth and Environmental Factors
Reminders
- Cell Anatomy Labs: Due on Monday at the start of class.
- Unit Exam: Scheduled for November 10th.
- Start reviewing now using notes or flashcards.
- Review session the Friday before the exam. New material taught by Wednesday.
Key Topics
Factors Affecting Plant Growth
- Abiotic Components: Non-living factors in an ecosystem.
- Sunlight
- Necessary for photosynthesis.
- Influences behavior of other organisms.
- Temperature
- Affects availability of liquid water.
- Freezing temperatures slow down metabolic processes.
- Water
- Essential for plant life.
- Availability affected by temperature.
- Wind
- Influences water availability and plant shape.
- Rocks and Soil
- Provides nutrients.
- Soil quality affects plant growth.
- Periodic Disturbances
- Events like fires and floods redistribute resources.
Plant Adaptations
- Hydrophytes: Plants adapted to very wet environments.
- Example: Water lilies, rice.
- Xerophytes: Plants adapted to very dry environments.
Biotic Factors
- Other Plants: Biggest competitor for resources like sunlight and water.
- Herbivores and Parasites: Affect plant health and growth.
- Decomposers: Help return nutrients to the soil.
Lab Design
- For the upcoming lab, focus on designing an experiment to test one factor affecting plant growth.
- Identify your variables and control factors.
- Develop a procedure but do not execute the experiment.
Miscellaneous Topics
- Thigmotropism: Plant growth response to touch, influenced by wind.
- Plant Dormancy: Preparation for harsh conditions by stopping chlorophyll production and dropping leaves.
Interesting Facts
- Some seeds require specific conditions or interactions (e.g., digestion by animals) to germinate.
- Geese Migration: Practiced through shorter flights before migrating south.
- Windbreak Effect: Trees growing in windy areas adapt by altering their growth pattern to avoid wind damage.
Conclusion
The lesson focused on understanding both abiotic and biotic factors affecting plant growth, along with the importance of these factors in experimental design. Plant adaptations to different environments were also discussed, giving insights into how they manage limited resources and react to environmental changes.