Plant Physiology and Ecology Quiz

Photosynthesis
- Process by which plants convert light energy into chemical energy (glucose).
- Occurs primarily in leaves within chloroplasts using chlorophyll.
- Equation: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂.
Plant Nutrition
- Essential nutrients: Macronutrients (N, P, K) and Micronutrients (Fe, Mn, Zn).
- Nutrient uptake occurs primarily through roots via soil solution.
- Role of mycorrhizae in enhancing nutrient absorption.
Water Regulation
- Transpiration: Loss of water vapor from plant surfaces, primarily through stomata.
- Role of xylem in water transport from roots to leaves.
- Stomatal regulation: Opens and closes to balance gas exchange and water loss.
Growth and Development
- Hormones: Auxins, gibberellins, cytokinins, ethylene, abscisic acid.
- Apical dominance: Growth of the main stem over lateral buds.
- Phototropism: Growth response to light direction.

Plant Interactions
- Symbiosis: Mutualism (e.g., pollinators and flowering plants), commensalism, parasitism.
- Competition: Interspecific (between species) and intraspecific (within species) for resources.
Ecosystems
- Role of plants as primary producers in food webs.
- Plant succession: Primary (new substrates) vs. secondary (disturbed areas) succession.
Habitat and Biodiversity
- Importance of plant diversity for ecosystem stability and resilience.
- Threats to plant biodiversity: Habitat destruction, invasive species, climate change.

Plant Evolutionary History
- Origin of land plants from green algae approximately 500 million years ago.
- Major groups: Bryophytes (mosses), Pteridophytes (ferns), Gymnosperms (conifers), Angiosperms (flowering plants).
Adaptations
- Structural adaptations: Cuticles, stomata, vascular tissues.
- Reproductive adaptations: Seeds, flowers, fruit.
Co-evolution
- Interactions with pollinators leading to diversification of flowering plants.
- Plant-herbivore co-evolution influencing plant defenses (e.g., thorns, toxins).

Plant Distribution
- Influenced by climate, soil types, and topography.
- Biogeography: Study of the distribution of plant species across geographical areas.
Ecoregions and Biomes
- Classification of regions based on climate, vegetation, and animal life (e.g., tropical rainforest, desert, tundra).
- Importance of understanding ecoregions for conservation efforts.
Adaptation to Climate
- Xerophytes: Plants adapted to arid environments (e.g., cacti).
- Hydrophytes: Plants adapted to aquatic environments (e.g., water lilies).
Human Impact
- Urbanization, deforestation, agriculture affecting plant distribution and diversity.
- Conservation strategies: Protected areas, restoration ecology, sustainable practices.

Photosynthesis converts light energy into chemical energy, producing glucose and oxygen. The process occurs in leaf chloroplasts containing chlorophyll.
The photosynthesis equation: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂.
Plant nutrition requires essential nutrients categorized into macronutrients (N, P, K) and micronutrients (Fe, Mn, Zn).
Nutrient uptake primarily happens through roots absorbing the soil solution, supported by mycorrhizal relationships that enhance absorption efficiency.
Transpiration is the process of water vapor loss from plant surfaces through stomata, aiding in cooling and nutrient transport.
Xylem vessels facilitate water transport from roots to leaves, crucial for photosynthesis and maintenance.
Stomata regulate gas exchange and water loss by opening and closing in response to environmental conditions.
Plant growth is influenced by hormones like auxins, gibberellins, and cytokinins, which play roles in processes such as apical dominance and phototropism.

Plant interactions include symbiosis types: mutualism (e.g., pollinators with flowering plants), commensalism, and parasitism.
Competition among plants can be interspecific (between species) or intraspecific (within species), affecting resource availability.
Plants are primary producers in ecosystems, forming the base of food webs and contributing to energy flow.
Plant succession, categorized as primary (occurring on new substrates) and secondary (following disturbances), demonstrates ecosystem dynamics.
Biodiversity is crucial for ecosystem stability, contributing to resilience against environmental changes and threats.
Threats to plant biodiversity include habitat destruction, invasive species introducing competition, and climate change altering habitats.

Land plants evolved from green algae around 500 million years ago, diversifying into major groups: Bryophytes (mosses), Pteridophytes (ferns), Gymnosperms (conifers), and Angiosperms (flowering plants).
Structural adaptations in plants include cuticles for moisture retention, stomata for gas exchange, and vascular tissues for efficient nutrient transport.
Reproductive adaptations such as seeds, flowers, and fruit enhance survival and reproductive success in various environments.
Co-evolution occurs between plants and pollinators, driving the diversification of flowering plants through mutual adaptations.
Interactions with herbivores have led to plant defenses, including physical structures like thorns and chemical defenses (toxins).

Plant distribution is affected by factors like climate, soil types, and topographic features, shaping regional biodiversity.
Biogeography studies the geographical distribution of plant species, influencing ecological research and conservation efforts.
Ecoregions are classified based on climate, vegetation, and associated animal life, aiding in understanding ecological dynamics.
Understanding ecoregions is vital for conservation strategies that seek to maintain biodiversity and ecosystem health.
Adaptations to climate are seen in xerophytes, which thrive in arid conditions (e.g., cacti), and hydrophytes, suited for aquatic environments (e.g., water lilies).
Human impacts such as urbanization, deforestation, and agricultural practices are leading to changes in plant distribution and diversity.
Conservation strategies include establishing protected areas, engaging in restoration ecology, and promoting sustainable land use practices.