plants__bio_106_

Study Guidelines for PLANTS

Key Identifying Characteristics of Each Plant Group:
- Understand the key features distinguishing major plant groups:
  - Bryophytes: Non-vascular plants such as mosses; typically found in moist environments, they require water for reproduction and do not have true roots, stems, or leaves.
  - Seedless Vascular Plants: Examples include ferns; they possess vascular tissue for transport, reproduce via spores, and have true roots, stems, and leaves.
  - Gymnosperms: Seed-producing plants like conifers that bear seeds on cones and have needle-like leaves; they are adapted to cold climates.
  - Angiosperms: Flowering plants that develop seeds within fruit; they exhibit diverse forms and often rely on animal pollination.
Review Lecture Notes and Lab Materials: Utilize visual aids, diagrams, and examples discussed in class to enhance understanding.
Familiarize with the Alternation of Generations Diagram: Recognize how this life cycle alternates between the haploid gametophyte and diploid sporophyte phases across different plant types.

Identify and Name Flower Parts:
- Petals: Attract pollinators, often brightly colored.
- Sepals: Protect the developing flower bud.
- Stamens: Male reproductive parts, consisting of anthers (which produce pollen) and filaments.
- Pistils: Female reproductive parts, including the ovary (which contains ovules), style, and stigma.

Label Seed Parts:
- Seed Coat: Protective outer layer; prevents desiccation.
- Embryo: The young plant, which will grow into a mature plant under suitable conditions.
- Endosperm: Nutrient-rich tissue that provides food for the developing embryo.

Know the Three Major Organ Systems:
- Roots: Function in anchoring the plant to the soil, nutrient absorption, and water uptake.
- Stems: Provide structural support, transport water and nutrients between roots and leaves, and may store food.
- Leaves: Primary sites for photosynthesis; also involved in gas exchange, aided by stomata openings.

Main Tissue Types:
- Dermal Tissue: Outer protective layer.
- Vascular Tissue: Comprises xylem (for water transport) and phloem (for nutrient transport).
- Ground Tissue: Functions in storage, photosynthesis, and support.

Xylem: Specialized for the upward transport of water; provides structural support through lignin.
Phloem: Responsible for the downward transport of sugars produced via photosynthesis, as well as distribution of nutrients.

Growth at Tips: Increases plant length; occurs at the apical meristems in roots and shoots, allowing for vertical expansion.

Increase in Thickness: Predominantly occurs in woody plants; involves the cambium layers forming new xylem and phloem, resulting in increased girth.

Plant and Microbe Relationships:
- Rhizobacteria: These beneficial bacteria in the soil enhance nutrient availability, particularly nitrogen, and promote root health.
- Mycorrhizal Fungi: Form symbiotic relationships with plant roots, improving water and nutrient absorption while also providing protection against pathogens.

Water Movement: Transpiration induces negative pressure within xylem vessels, pulling water upward; this process is critical for maintaining plant hydration.
Role of Stomata: Small openings on leaves facilitate gas exchange and regulate water loss; they close during drought to minimize evaporation.

Understanding Source to Sink Transport: Sugars synthesized in leaves (sources) are transported to growing tissues (sinks) such as roots and fruits through phloem.

Balancing Act: Plants must manage the trade-off between maximizing CO2 intake for photosynthesis and minimizing water loss, which is crucial for survival, especially in arid conditions.

Key Hormones:
- Auxins: Promote stem elongation and directional growth.
- Gibberellins: Stimulate seed germination and growth.
- Cytokinins: Promote cell division and shoot development.
- Abscisic Acid: Involved in stress responses and stomatal closure.
- Ethylene: Regulates fruit ripening and response to stress.

Plant Responses: Recognize how plants react to stimuli, including:
- Light Quality: Phototropism, where plants grow towards light.
- Gravitropism: Roots grow downward, and shoots grow upward in response to gravity.
- Mechanisms of Response: Focus on the concepts rather than intricate biochemical mechanics.

Exam Preparation: Your performance on exams significantly impacts your course grade; striving for higher scores not only reflects understanding but can also benefit overall grades, particularly in conjunction with final exam performance.