Plant Diversity, Adaptations, and Life Cycles

Vocabulary flashcards covering terrestrial plant evolution, major plant clades, adaptations, life cycles, and reproductive strategies.

Charophytes

Green algae that the common ancestor of land plants may have resembled.

Cuticle

A waterproof barrier found on plants that conserves water.

Stomata

Specialized structures on plants that conserve water and help regulate resource exchange.

Vascular Tissue

An internal transportation system in plants that moves materials between specialized plant parts and provides physical support.

Xylem

A type of vascular tissue responsible for transporting water and minerals throughout a plant.

Phloem

A type of vascular tissue responsible for transporting sugars throughout a plant.

Lignin

A complex polymer that strengthens xylem cell walls to provide physical support for the plant body.

Sporophyte

The diploid ($2n$) generation in the plant life cycle that produces haploid spores through meiosis.

Gametophyte

The haploid ($n$) generation in the plant life cycle that produces haploid gametes through mitosis.

Pollen Grains

Structures produced by gymnosperms and angiosperms that transport male sex cells without requiring free water.

Seeds

Structures produced by gymnosperms and angiosperms that protect and nourish the plant embryo, packaging it alongside a food supply.

Bryophytes

Small nonvascular plants lacking leaves, roots, and stems; they possess a dominant gametophyte generation, an nutritionally dependent sporophyte, and swimming sperm requiring water.

Seedless Vascular Plants

Plants possessing xylem and phloem but lacking seeds, characterized by an independent sporophyte generation and swimming sperm; includes club mosses, whisk ferns, horsetails, and true ferns.

Sporangia

Collections of reproductive structures located on the undersides of fern fronds where meiosis occurs to generate haploid spores.

Gymnosperms

Vascular plants with 'naked seeds' that are not enclosed in fruits, encompassing cycads, ginkgos, conifers, and gnetophytes.

Cones

Reproductive structures in conifers; male cones release pollen, while female cones house ovules that produce egg cells.

Ovules

Structures inside female pine cones and flowers within which egg cells are produced.

Pollen Tube

A structure produced upon pollen germination through which a sperm nucleus travels to reach the egg cell.

Angiosperms

Vascular plants that develop flowers and fruits, with seeds enclosed inside fruits; the two largest clades are eudicots and monocots.

Fruit

A structure that develops from a flower after pollination, serving to protect maturing seeds and assist in dispersal by wind or animals.

Coevolution

The reciprocal, corresponding evolutionary adaptations between plants and animal pollinators.

Endosperm

Nutritive tissue in an angiosperm seed that forms when one of the two sperm nuclei delivered by pollen fertilizes a pair of nuclei in the female gametophyte's central cell.