Plant Evolution and Classification Vocabulary

Plant Adaptations and Structures

• Cuticle: A waxy layer that covers plant surfaces to minimize water loss, crucial for survival in terrestrial environments.
• Spore: A haploid reproductive cell encased in a tough outer wall, enabling survival in harsh conditions.
• Seed: Consists of an embryo with a protective coating, allowing plants to reproduce successfully.

Plant Tissues

• Endosperm: Nutritive tissue that supports the developing plant embryo inside the seed.
• Vascular tissue: Essential for transporting water and nutrients throughout the plant, comprising two main types.
• Xylem: Responsible for transporting water and inorganic nutrients from roots to other parts of the plant in a unidirectional flow.
• Phloem: Transports organic compounds like carbohydrates and some nutrients throughout the plant, functioning bidirectionally.

Plant Types and Characteristics

• Woody tissue: Formed from multiple layers of xylem, typically found centrally in stems, contributing to structural support.
• Herbaceous plants: Soft, non-woody plants characterized by green stems.
• Nonvascular plants: Lack specialized tissues for transport, do not have true roots, stems, or leaves; examples include mosses.
• Vascular plants: Possess true roots, stems, and leaves with specialized conducting tissues for efficient nutrient and water transport.
• Seed plants: Reproduce by producing seeds, encompassing gymnosperms and angiosperms.
• Gymnosperms: Non-flowering plants that produce seeds not enclosed by fruits.
• Angiosperms: Flowering plants that produce seeds within a protective fruit.

Life Cycle and Reproductive Phases

• Sporophyte: The diploid phase of the plant life cycle that generates haploid spores for reproduction.
• Gametophyte: The haploid phase that produces gametes necessary for sexual reproduction.
• Alternation of generations: A life cycle strategy where plants alternate between sporophyte and gametophyte stages.

Nonvascular Plants

• Bryophytes: Includes three phyla of nonvascular plants, characterized by dependence on water for reproduction.
• Rhizoids: Structures anchoring gametophytes to the soil, functioning similarly to roots.

Ferns and Other Features

• Sphagnum: A type of peat moss, significant for water retention and carbon storage.
• Thalloid: A flat plant body exhibiting clear upper and lower surfaces.
• Strobilus: A reproductive structure resembling a cone, comprising sporangia-bearing modified leaves.
• Rhizome: An underground stem that serves as a storage organ and means of vegetative reproduction.
• Fiddleheads: The tightly coiled new leaves of ferns, emerging in spring.
• Fronds: Developed leaves that unfold from fiddleheads.

Germination and Seedlings

• Germinate: The process by which a seed embryo begins to develop and grow into a new plant.
• Seedling: An early developmental stage of a plant emerging from the seed.

Reproductive Structures

• Cone: A structure containing reproductive components, usually consisting of hard scales.
• Deciduous trees: Trees that shed their leaves in autumn, adapting to seasonal changes.
• Ovary: The part of the flower that encloses the ovules, protecting the developing seeds.

Cotyledons and Plant Classification

• Cotyledons: Seed leaves that provide initial nutrients to the developing plant embryo.
• Monocots: Plants characterized by a single cotyledon, typically exhibiting parallel venation.
• Dicots: Plants with two cotyledons, often displaying net venation in leaves.
• Veins: Bundles of vascular tissue that facilitate transportation within leaves.
• Parallel venation: A leaf structure where veins run parallel to each other.
• Net venation: A branching pattern of veins forming an interconnected network within leaves.