Plant Anatomy and Physiology Quiz

Plant Anatomy

• Basic Structure

  • Roots: Anchor plants; absorb water and nutrients.
  • Stems: Support; transport nutrients and water; store food.
  • Leaves: Main site of photosynthesis; gas exchange through stomata.

• Tissue Types

  • Meristematic: Actively dividing cells; found in growth regions (apical and lateral meristems).
  • Permanent: Specialized cells; includes:
    • Dermal: Protective outer layer (epidermis).
    • Vascular: Transport (xylem for water, phloem for nutrients).
    • Ground: Photosynthesis, storage, and support.

Plant Physiology

• Photosynthesis

  • Process converting light energy into chemical energy (glucose).
  • Occurs mainly in chloroplasts; involves chlorophyll.
  • Two stages: Light-dependent reactions and Calvin cycle (light-independent reactions).

• Transpiration

  • Water movement through plants; evaporation from leaf surfaces.
  • Helps in nutrient transport and temperature regulation.

• Respiration

  • Process of breaking down glucose to release energy (ATP).
  • Occurs in mitochondria; involves glycolysis, the Krebs cycle, and oxidative phosphorylation.

• Growth Regulators

  • Hormones influencing growth and development:
    • Auxins: Promote cell elongation.
    • Gibberellins: Stimulate stem elongation and seed germination.
    • Cytokinins: Promote cell division.
    • Abscisic Acid: Inhibits growth; helps plants respond to stress.

Plant Genetics

• Basic Concepts

  • Genes: Units of heredity; located on chromosomes.
  • Alleles: Different forms of a gene; can be dominant or recessive.

• Plant Breeding

  • Techniques for improving plant varieties:
    • Selective breeding: Choosing specific plants for desirable traits.
    • Hybridization: Cross-breeding different varieties to combine traits.

• Genetic Engineering

  • Techniques like CRISPR used to modify plant genomes for desired characteristics (e.g., pest resistance, increased yield).

• Genomics

  • Study of an organism's complete set of DNA, including genes and their functions.
  • Important for understanding plant evolution and diversity.

Plant Ecology

• Ecosystem Roles

  • Primary producers: Convert solar energy into biomass.
  • Habitat: Provide shelter and food for various organisms.

• Adaptations

  • Physiological: Drought resistance through CAM photosynthesis.
  • Morphological: Thick leaves for water retention; deep roots for nutrient access.

• Interactions

  • Mutualism: Symbiotic relationships (e.g., pollinators and flowering plants).
  • Competition: For light, nutrients, and space among plant species.

Plant Anatomy

• Roots anchor plants and are responsible for absorbing water and nutrients.
• Stems support the plant structure, transport essential nutrients and water, and store food.
• Leaves are the primary site for photosynthesis and facilitate gas exchange through structures called stomata.
• Meristematic tissue consists of actively dividing cells, found in growth regions such as apical and lateral meristems.
• Permanent tissue types include:
  • Dermal tissue forms the protective outer layer, known as the epidermis.
  • Vascular tissue is responsible for transport; xylem carries water, while phloem transports nutrients.
  • Ground tissue performs functions such as photosynthesis, storage, and providing structural support.

Plant Physiology

• Photosynthesis transforms light energy into chemical energy, specifically glucose, occurring mainly in chloroplasts and involving chlorophyll.
• Photosynthesis consists of two main stages: the light-dependent reactions and the Calvin cycle, which are light-independent.
• Transpiration describes the movement of water through plants and its evaporation from leaf surfaces, playing a crucial role in nutrient transport and temperature regulation.
• Respiration is the biochemical process that breaks down glucose to release energy in the form of ATP, occurring in mitochondria and involving glycolysis, the Krebs cycle, and oxidative phosphorylation.
• Growth regulators are hormones that affect various aspects of plant growth and development; they include:
  • Auxins, which promote cell elongation.
  • Gibberellins, which stimulate stem elongation and seed germination.
  • Cytokinins, which encourage cell division.
  • Abscisic acid, which inhibits growth and mediates stress responses.

Plant Genetics

• Genes are the hereditary units located on chromosomes; they are fundamental to genetic inheritance.
• Alleles represent different forms of a gene, classified as dominant or recessive.
• Plant breeding techniques aim to enhance plant varieties through:
  • Selective breeding, focusing on specific plants with desirable traits.
  • Hybridization, involving cross-breeding of different varieties to produce offspring with combined beneficial traits.
• Genetic engineering employs advanced techniques, such as CRISPR, to alter plant genomes for desired characteristics, including pest resistance and increased yields.
• Genomics encompasses the comprehensive study of an organism's DNA, including genes and their functions, helping to elucidate plant evolution and diversity.

Plant Ecology

• Plants serve as primary producers in ecosystems, converting solar energy into biomass.
• They provide habitats and food sources for various organisms, playing critical roles in maintaining ecological balance.
• Adaptations in plants include:
  • Physiological adaptations, such as CAM photosynthesis, which enhances drought resistance.
  • Morphological adaptations, like thick leaves for water retention and deep roots for accessing nutrients.
• Plant interactions involve:
  • Mutualism, exemplified by the relationships between pollinators and flowering plants.
  • Competition among plant species for vital resources like light, nutrients, and space.

Test your knowledge on the basic structures of plants, including roots, stems, and leaves, as well as their functions. Explore tissue types such as meristematic and permanent tissues, and understand essential processes like photosynthesis and transpiration.