Introduction to Plant Biology – Key Vocabulary

A comprehensive set of vocabulary flashcards covering plant evolution, anatomy, adaptation, and reproduction, designed to reinforce key terms from the lecture.

Plantae

The biological kingdom that includes all multicellular, photosynthetic organisms with cellulose-based cell walls.

Multicellular eukaryote

An organism composed of many cells whose DNA is enclosed within nuclei; all plants fit this description.

Cellulose

A structural polysaccharide that forms the rigid cell walls of plants.

Chlorophyll a & b

Green pigments in chloroplasts that capture light energy for photosynthesis.

Charophytes

A modern group of green algae considered the closest living relatives of the first land plants.

Cuticle

A waxy, waterproof coating on plant surfaces that reduces desiccation (water loss).

Drought tolerance

Adaptations, such as water storage in tissues, that enable plants to survive prolonged dry periods.

Pollen

A protective, microscopic grain that carries sperm cells in seed plants, enabling reproduction without standing water.

Vascular system

A network of conducting tissues (xylem and phloem) that transports water, minerals, and sugars throughout a plant.

Lignin

A strong, complex polymer that hardens certain cell walls, giving plants structural support to stand upright.

Mycorrhizae

A mutualistic association between plant roots and fungi in which fungi supply water/minerals and receive sugars.

Shoot system

The above-ground portion of a plant (stems, leaves, flowers) responsible for photosynthesis, reproduction, and transport.

Root system

The below-ground portion of a plant that anchors, absorbs water/nutrients, stores food, and sends hormones upward.

Bryophytes

Non-vascular, seedless plants (mosses, liverworts, hornworts) that stay small and live in moist habitats.

Liverworts

A type of bryophyte that often carpets bark or soil with flat, lobed thalli.

Hornworts

Bryophytes distinguished by horn-shaped sporophytes growing from a flattened gametophyte.

Mosses

The most common bryophytes; include peat moss, valued for gardening and floral uses.

Alternation of generations

A plant life cycle alternating between a haploid gametophyte stage and a diploid sporophyte stage.

Gametophyte

The haploid, gamete-producing generation of a plant life cycle.

Sporophyte

The diploid, spore-producing generation of a plant life cycle.

Xylem

Dead, tubular cells that move water and minerals upward from roots via transpiration.

Phloem

Living cells arranged in tubes that transport sugar-rich sap from a source to a sink.

Transpiration

The physical process that pulls a continuous column of water up xylem as water evaporates from leaves.

Lycophytes

Ancient lineage of seedless vascular plants that includes club mosses and their relatives.

Ferns

Seedless vascular plants with fronds; common in tropical and temperate forests.

Gymnosperms

Seed plants, such as conifers, that produce naked seeds on cones rather than enclosed within fruit.

Cone

The reproductive structure of gymnosperms; female cones contain ovules and male cones produce pollen.

Pollen tube

A tube grown by a pollen grain that delivers sperm to an ovule in seed plants.

Conifers

Cone-bearing gymnosperms (pine, fir, redwood) notable for woody trunks and needle-like leaves.

Ginkophyte

The gymnosperm division containing the single living species Ginkgo biloba, known for pollution tolerance.

Angiosperms

Flowering plants that protect seeds within fruits; the most diverse group of modern plants.

Flower

A reproductive organ of angiosperms that facilitates pollination and houses ovules.

Stamen

The male flower part consisting of an anther and filament; produces pollen.

Anther

The pollen-producing portion of a stamen.

Filament

The stalk that supports the anther within a staminate flower.

Carpel

The female flower structure composed of stigma, style, and ovary.

Stigma

Sticky tip of a carpel that captures pollen.

Style

Slender stalk through which sperm travel from stigma to ovary.

Ovary

The basal part of a carpel that encloses ovules and develops into fruit after fertilization.

Double fertilization

Angiosperm process in which one sperm forms a zygote and a second forms triploid endosperm for nourishment.

Endosperm

Nutrient-rich tissue in angiosperm seeds that feeds the developing embryo.

Fruit

A mature ovary that surrounds seeds and aids in their protection and dispersal.

Cotyledon

The first seed leaf (or leaves) of a plant embryo; basis for classifying monocots and dicots.

Monocot

An angiosperm with one cotyledon, parallel-veined leaves, flower parts in threes, and fibrous roots.

Dicot

An angiosperm with two cotyledons, net-veined leaves, flower parts in fours or fives, and a taproot.