Plants and Humans ASYNC Exam 1

Photosynthesis

Process by which green plants convert light energy, CO₂, and water into glucose and release O₂

Oxygen production

Crucial service plants provide to humans as a by-product of photosynthesis

Shelter (plant role)

Protection humans gain from plant materials such as wood or leaves

Soil stabilization

Roots prevent erosion and keep soil in place

Plant toxins

Chemical compounds produced by some plants that can poison or harm animals and humans

Spines

Sharp outgrowths on plants that deter herbivores

Allergies (plant)

Adverse immune reactions in humans triggered by pollen or other plant products

Cultivation

Human practice of growing and managing crop plants

Conservation of habitats

Efforts to protect natural plant environments, such as tropical forests

Habitat destruction

Loss of plant environments due to urbanization or other human activities

Photosynthetic organism

Life-form able to make its own food from light, CO₂, and water

Green alga (Chara)

Aquatic photosynthetic organism closely related to land plants

Bryophyte

Non-vascular plant group that includes mosses, liverworts, and hornworts

Vascular plant

Plant possessing xylem and phloem for internal transport

Fern

Seedless vascular plant reproducing by spores borne under leaves

Seed plant

Vascular plant that reproduces via seeds; includes gymnosperms & angiosperms

Cycad

Gymnosperm with palm-like appearance and large seed cones

Conifer

Gymnosperm producing cones and needle-like leaves (e.g., pines)

Angiosperm

Flowering plant; largest group of seed plants

Flowering plant

Common term for angiosperm; produces flowers and enclosed seeds

Cone

Reproductive structure of conifers and cycads containing seeds

Fern allies

Seedless vascular plants related to ferns (horsetails, clubmosses, spike-mosses)

Bryophyte examples

Mosses, liverworts, and hornworts lacking vascular tissue

Coral

Marine animal colony; not a plant

Mushroom

Fungal fruiting body; heterotrophic, not a plant

Stem

Plant organ that supports leaves and transports substances

Leaf

Plant organ specialized for photosynthesis, usually broad and thin

Root

Underground organ absorbing water/nutrients and anchoring plant

Shoot

Collective term for a plant’s stems and leaves

Node

Point on stem where a leaf or branch attaches

Internode

Stem segment between two nodes

Petiole

Stalk connecting a leaf blade to the stem

Vein (leaf)

Strand of vascular tissue within a leaf

Root tip

Growing end of a root containing root cap and apical meristem

Root cap

Protective tissue covering root apical meristem

Root apical meristem

Region of active cell division at the root tip

Zone of elongation

Root region where cells increase in length

Zone of maturation

Root area where cells differentiate and root hairs form

Root hair

Tiny epidermal extension that increases root surface area

Lateral root

Secondary root emerging from the main root system

Tap root system

Root system with one dominant primary root (e.g., carrot)

Fibrous root system

Many similarly sized roots branching in all directions (e.g., grasses)

Flower (plant organ)

Reproductive structure bearing sepals, petals, stamens, and carpels

Sepal

Green flower part that protects developing bud

Petal

Often colorful flower part that attracts pollinators

Stamen

Male reproductive part of a flower, consisting of filament and anther

Anther

Pollen-producing sac at top of stamen

Filament

Stalk that supports the anther

Carpel (pistil)

Female reproductive part composed of stigma, style, and ovary

Stigma

Sticky surface of carpel where pollen lands

Style

Tube connecting stigma to ovary

Ovary (flower)

Encloses ovules; matures into fruit after fertilization

Ovule

Structure containing egg cell; develops into a seed

Fruit

Mature ovary surrounding seeds

Seed

Plant embryo with stored food and protective coat

Diffuse growth

Growth throughout the body; typical of animals

Localized growth

Growth restricted to meristems; typical of plants

Determinate organogenesis

Fixed number and size of organs (common in animals)

Indeterminate organogenesis

Continuous formation of new organs (common in plants)

Annual plant

Completes life cycle in one year or less

Biennial plant

Lives two years, flowering in the second

Perennial plant

Lives more than two years, often flowering annually after maturity

Juvenile phase

Non-reproductive growth stage of a plant

Adult phase

Reproductive stage when plant produces flowers or cones

Herbaceous stem

Green, flexible stem lacking woody tissue

Woody stem

Brown, rigid stem with bark

Organelle

Specialized structure within a cell performing a specific function

Cell wall

Rigid cellulose layer maintaining plant cell shape

Plasma membrane

Selectively permeable boundary surrounding cytoplasm

Cytoplasm

Jellylike matrix housing organelles inside the cell

Nucleus

Double-membrane organelle containing DNA

Central vacuole

Large, fluid-filled organelle for storage and turgor maintenance

Plastid

Plant organelle class including chloroplasts, chromoplasts, amyloplasts

Proplastid

Undifferentiated plastid in meristematic cells

Chloroplast

Plastid that carries out photosynthesis

Chromoplast

Plastid storing pigments other than chlorophyll

Amyloplast

Plastid storing starch in roots or tubers

Mitochondrion

Organelle generating ATP through cellular respiration

Rough ER

Endoplasmic reticulum with ribosomes; synthesizes proteins

Smooth ER

Endoplasmic reticulum without ribosomes; synthesizes lipids

Ribosome

Site of protein synthesis; not membrane-bound

Microtubule

Cytoskeletal element providing structure and aiding transport

Microfilament

Fine cytoskeletal fiber involved in movement and support

Cytosol

Liquid component of cytoplasm

Intercellular spaces

Air spaces between plant cells facilitating gas exchange

Parenchyma cell

Living, thin-walled plant cell specialized for metabolism and storage

Collenchyma cell

Living cell with unevenly thickened walls providing flexible support

Sclerenchyma cell

Dead, thick-walled cell with lignin for rigid support

Epidermis (plant)

Outermost tissue layer covering plant organs

Cuticle

Waxy layer on epidermis reducing water loss

Stoma (stomata)

Pore for gas exchange in epidermis

Guard cell

Pair of cells controlling stoma opening

Trichome

Hair-like epidermal outgrowth

Phloem

Vascular tissue transporting sugars throughout the plant

Xylem

Vascular tissue conducting water and minerals upward

Monocot

Flowering plant with one cotyledon and scattered stem vascular bundles

Dicot

Flowering plant with two cotyledons and ringed stem vascular bundles

Root hair (function)

Absorbs water and nutrients; increases surface area

Mesophyll

Photosynthetic tissue inside leaves

Palisade mesophyll

Column-shaped cells rich in chloroplasts under upper epidermis