Gymnosperms and Angiosperms

Flashcards covering gymnosperm classification, characteristics, cycads, ginkgoes, gnetophytes, angiosperm structure, pollination, seeds, fruits, dispersal, domestication, families, and the Anthropocene.

Conifers (Phylum Pinophyta)

Largest and most diverse group of living gymnosperms, producing seeds typically in woody cones. Many are monoecious.

Cycads (Phylum Cycadophyta)

Dioecious gymnosperms that dominated the landscape during the Jurassic period. Cycad sperm have flagella and can swim.

Ginkgoes (Phylum Ginkgophyta)

Gymnosperms with only one living species, Ginkgo biloba. They have flattened, deciduous leaves with dichotomously branching veins and motile sperm.

Gnetophytes (Phylum Gnetophyta)

Gymnosperms believed to be most closely related to flowering plants. Includes Gnetum, Ephedra, and Welwitschia.

Angiosperms (Phylum Anthophyta)

Flowering plants, divided into Monocotyledonae and Eudicotyledonae. Flowers contain a peduncle, receptacle, sepals (calyx), petals (corolla), stamens (androecium), and carpels (gynoecium).

Complete Flowers

Flowers having all four whorls: sepals, petals, stamens, and carpels.

Perfect Flowers

Flowers bearing both stamens and carpels in the same flower.

Pollen Grain

The male gametophyte in flowering plants; develops inside reproductive structures.

Embryo Sac

The female gametophyte in flowering plants; develops inside the ovule.

Double Fertilization

Process in angiosperms where one sperm cell fertilizes the egg, forming the diploid zygote, and the other sperm cell combines with the two polar nuclei, forming the triploid endosperm.

Exocarp

Skin of the ovary that becomes the outside of the fruit.

Endocarp

Innermost layer of the ovary closest to the ovules, forming the inner boundary around the seeds.

Mesocarp

Everything between the exocarp and the endocarp in a fruit.

Pericarp

The three layers of a fruit (exocarp, mesocarp, and endocarp) together.

Aggregate Fruits

Fruits that form from single flowers that have multiple pistils, with each pistil developing into a fruitlet (e.g., raspberries, blackberries, strawberries).

Multiple Fruits

Fruits that develop from multiple flowers in a single inflorescence, where the ovaries of the individual flowers develop into fruitlets that grow together (e.g., pineapples).

Dehiscent Fruits

Dry fruits that split open when ripe, releasing the seeds.

Indehiscent Fruits

Dry fruits that stay intact when ripe.

The Neolithic Agricultural Revolution

The development of agriculture brought profound changes to human lives: Transition from nomadic to sedentary lifestyle, Greater population density, Division of labor.

Spices

Strongly flavored plant parts, usually rich in essential oils, from roots, bark, seeds, fruits, or buds.

Herbs

Usually the leaves of nonwoody plants.

Orchidaceae

A diverse monocot family with irregular flower patterns, often possessing pseudobulbs.

Poaceae

The grass family, a monocot with tiny, modified flowers in inflorescences and leaves with a blade and sheath.

Asteraceae

The daisy family, a dicot with clusters of tiny blooms fused together into a head (inflorescence).

Fabaceae

The legume family, a dicot characterized by fruits called legumes (pods) that split along both seams.

Cactaceae

A dicot family of plants that usually lack leaves, have spines, fleshy berries, and perform photosynthesis in stems.

Brassicaceae

The cabbage family, a dicot which include broccoli, Brussels sprouts, cauliflower, cabbage, kale, radishes, and turnips.

Amaranthaceae

The amaranth family, a dicot with conspicuous, spike-like flower heads made up of small or tiny, unremarkable bisexual flowers.

Solanaceae

The potato family, a dicot with flowers with five fused petals and five prominent yellow anthers held together in a point at the center of the flower.

The Anthropocene

A proposed new geological epoch defined by the significant impact of human activity on Earth's geology and ecosystems.

Invasive plants

Plant species that become widespread thanks to human transport and who are harmful to the ecosystems they invade since their populations tend to grow uncontrollably.

Holocene extinction

The sixth mass extinction in the planet's history, impacting plants and animals due to land use changes, overexploitation, and climate change.

Plant biotechnology

The efforts to feed humanity through transgenic crops may be the key to safely increasing crop yields and improving nutritional value.