Plant Biology Vocabulary Review

Flashcards covering key vocabulary terms and definitions related to plant biology.

Non-vascular plant / Bryophytes

Plants that lack vascular tissue (xylem and phloem) and transport water by osmosis; includes mosses and liverworts.

Vascular plant

Plants that have specialized tissue (xylem and phloem) for transporting water, minerals, and food.

Lignin

A complex organic compound that hardens cell walls and provides support in vascular plants.

Ferns

Seedless vascular plants that reproduce using spores and have large divided leaves called fronds.

Frond

A large, divided leaf of a fern.

Spores

Reproductive cells capable of developing into a new organism without fusion with another cell.

Gymnosperms

Vascular plants that produce seeds not enclosed in fruit; includes conifers.

Conifers

Cone-bearing gymnosperms like pine and spruce.

Pollen

Powdery substance containing male gametes; allows for reproduction without water.

Angiosperms

Flowering vascular plants that produce seeds enclosed in fruit.

Monocot

Angiosperm with one seed leaf (cotyledon), parallel leaf veins, and flower parts in multiples of three.

Dicot

Angiosperm with two seed leaves, net-like veins, and flower parts in multiples of four or five.

Roots

Underground organs that anchor the plant and absorb water and nutrients.

Fibrous roots

A root system with many thin roots of similar size (common in monocots).

Tap root

A large central root with smaller branches (common in dicots).

Root hairs

Tiny extensions of root epidermal cells that increase surface area for absorption.

Root cap

Protective structure at the tip of a root that protects the apical meristem.

Stems

Support structures that transport water, nutrients, and sugars through the plant.

Herbaceous stems

Soft, green, and flexible stems.

Woody stems

Rigid stems with wood and bark that allow for secondary growth.

Leaves

Plant organs responsible for photosynthesis and gas exchange.

Cuticle

Waxy, waterproof layer that covers the leaf and prevents water loss.

Epidermis

Outer protective layer of cells in leaves and stems.

Mesophyll

Inner tissue of the leaf where most photosynthesis occurs.

Stomata

Small pores on the underside of a leaf for gas exchange.

Guard cell

Specialized cells that open and close stomata.

Vein

Vascular bundle in a leaf containing xylem and phloem.

Xylem

Vascular tissue that carries water and minerals from roots to leaves.

Phloem

Vascular tissue that transports sugars from leaves to other parts of the plant.

Petiole

Stalk that connects the leaf blade to the stem.

Blade

The broad, flat part of a leaf.

Tissues

Groups of specialized cells performing specific functions.

Dermal tissue

Outer protective covering of a plant.

Vascular tissue

Transport system made of xylem and phloem.

Ground tissue

Fills the space between dermal and vascular tissues; involved in photosynthesis and storage.

Meristematic tissue

Regions of undifferentiated cells where growth occurs.

Primary growth

Growth in length occurring at the tips of roots and shoots.

Secondary growth

Growth in thickness, usually in woody plants.

Cohesion–tension theory

Explains water movement in plants: water is pulled upward due to cohesion and transpiration.

Pressure–flow hypothesis

Explains sugar transport in phloem from source to sink areas by pressure differences.

Cells

Basic structural units of plant tissues.

Parenchyma

Thin-walled cells involved in photosynthesis and storage.

Collenchyma

Flexible cells that support growing parts of the plant.

Sclerenchyma

Thick, rigid cells that provide structural support.

Alternation of generations

Plant life cycle alternating between haploid (gametophyte) and diploid (sporophyte) stages.

Haploid

Having a single set of chromosomes (n).

Diploid

Having two sets of chromosomes (2n).

Gametophyte

The haploid stage that produces gametes.

Sporophyte

The diploid stage that produces spores.

Pollination

Transfer of pollen from the male anther to the female stigma.

Self-pollination

Pollen from the same plant fertilizes the ovule.

Cross-pollination

Pollen from one plant fertilizes the ovule of another.

Flower

The reproductive structure of angiosperms.

Sepal

Outer leaf-like parts that protect the flower bud.

Petal

Colorful structures that attract pollinators.

Stamen

Male reproductive part.

Filament

Stalk supporting the anther.

Anther

Produces pollen.

Pistil (carpel)

Female reproductive part.

Stigma

Sticky tip that captures pollen.

Style

Tube leading to the ovary.

Ovary

Contains ovules.

Ovule

Structure that develops into a seed after fertilization.

Egg

Female gamete inside the ovule.

Receptacle

Base of the flower where floral organs attach.

Complete flower

Has all four main floral parts: sepals, petals, stamens, and pistils.

Incomplete flower

Lacks one or more of the four floral parts.

Double fertilization

One sperm fertilizes the egg; another sperm fuses with two nuclei to form endosperm.

Fruit

A mature ovary that protects and helps disperse seeds.

Seed

A plant embryo and a food supply, encased in a protective covering.

Embryo

The young plant inside the seed.

Cotyledon

Seed leaf that stores or absorbs nutrients.

Endosperm

Tissue that nourishes the developing embryo.

Seed coat

Protective outer layer of a seed.

Germination

The process by which a seed develops into a new plant.

Transpiration

The evaporation of water from plant leaves, pulling water upward from roots.

Tropisms

Growth responses to environmental stimuli.

Phototropism

Growth toward light.

Gravitropism

Growth in response to gravity.

Thigmotropism

Growth in response to touch.

Hormones

Chemical signals that regulate plant growth and development.

Auxins

Promote elongation of cells; inhibit growth of side branches.

Ethylene gas

Promotes fruit ripening.

Gibberellins

Stimulate stem elongation, germination, and flowering.

Cytokinins

Promote cell division and growth of lateral buds.

Photoperiodism

A plant's response to the length of daylight and darkness.

Plant adaptations

Structural or physiological traits that improve survival and reproduction in a specific environment.

Annual

Completes its life cycle in one growing season.

Biennial

Takes two years to complete its life cycle.

Perennial

Lives for more than two years.

Regeneration

Ability to regrow from a piece of the plant.

Vegetative reproduction

Asexual reproduction through vegetative parts like roots, stems, or leaves.

Stolons

Horizontal stems above ground that form new plants.

Rhizomes

Underground stems that grow horizontally.

Tubers

Swollen underground stems that store nutrients (e.g., potatoes).

Bulbs

Underground stems surrounded by modified leaves (e.g., onions).

Vegetative propagation

Human-assisted method to grow new plants from existing ones.

Grafting

Joining parts from two plants to grow as one.

Cutting

Growing a new plant from a cut portion of the original plant.