The plant is a living organism that makes its own food. It usually consists of root, stem, and leaves.
The leaves are the thin and flattened blades on the plant. They grow on the stem and are veined and usually green in color. They are the food-making organs of the plant.
The stem generally grows above the ground. It bears branches, leaves, buds, flowers, and fruit, and connects these with the root. The tip or apex is called the growing point.
The root generally grows underground and bears no leaves or flowers. It grows downward and takes in water and dissolved minerals from the soil. It fixes the plant to the ground.
A branch is a woody stem extending from the main stem, or trunk, of a tree. A twig is a small woody branch.
A plant is called a tree when it has a single main woody (usually brown) stem with branches on only the upper part of the plant. The main stem is called a trunk.
A plant is called an herb when it has an herbaceous (usually green) stem which does not live over from year to year.
A plant is called a shrub when it has no main stem but has a number of woody branches arising from ground level.
A plant is called a vine when it has a stem that needs support. Ex. English ivy, morning-glory, grape
A tendril is a slender, coiling part which aids in the support of the plant stem. It can be a modified branch (wild grape), leaf (wild cucumber), or leaflet (sweet pea).
A thorn is a short, hard, leafless branch or stem with a sharp point. Ex. pyracantha
A prickle is a sharp pointed extension of the outer layer of stem tissue. Prickles are located along the internodes of the stem. Ex. rose
A spine is a sharp structure formed from a leaf (barberry) or stipule (black locust).
The Leaf
Leaf (Parts of the Leaf)
A leaf is the thin and flattened blade on the plant. It grows on the stem and is veined and usually green in color. Leaves are the food-making parts of plants.
The veins are tubes that carry food and water to other parts of the plant. They also help to keep the leaf strong so that it is not easily torn by the wind.
The blade or lamina is the flattened part of the leaf.
The petiole is the narrow stalk of the leaf which joins the blade to the stem.
The stipules are the leaf-like structures found at the base of the petiole of many plants. They cover and protect the young leaf bud.
Parts of the Leaf Blade
The margin is the outer edge of the leaf blade.
The apex is the tip of the leaf blade.
The base is the part of the blade where the petiole is attached.
The midrib is a large main vein which extends from the petiole to the apex of the leaf.
The lateral veins are veins which branch out on either side of the midrib.
Leaf Venation
The netted (reticulate) veins branch and intersect each other, forming a network.
A leaf with parallel venation is one in which the veins proceed from the base to the tip of the leaf in a parallel fashion. Ex. grass, lily
A leaf with pinnate venation has one primary vein (or midrib) with smaller veins branching from it as in a feather. Ex. oak, beech, cherry
A leaf with palmate venation has more than one primary vein. These veins branch out from the apex of the petiole like the fingers of a hand. Ex. ivy, maple
Leaf Shapes
See our detailed lesson and worksheets onLeaf Shapes.
An acicular leaf is shaped like a needle – very slender, narrow, and pointed. Ex. pine, fir
A cordate leaf is shaped like a heart. Ex. lilac, violet
An obcordate leaf is shaped like a heart, but with the point of the heart at the base of the leaf. Ex. white clover
A deltoid (triangular) leaf is shaped like an equilateral triangle. The petiole is attached in the middle of one of the sides. Ex. climbing hempweed, garlic mustard
An elliptical leaf is shaped like an ellipse, usually more than twice as long as broad. Ex. serviceberry, Southern magnolia
A hastate leaf is triangular with the basal lobes spread out, resembling the shape of an arrowhead. Ex. hedge bindweed, arrow-leaf violet
A lanceolate leaf is narrow and lance-shaped, tapering from a broad base to the tip (apex). Ex. phlox, evening primrose
An oblanceolate leaf has the shape of a lance, but with the broadest part toward the tip (apex). Ex. common mullein, slender goldenrod
A linear leaf is long and narrow, its sides being somewhat parallel. It is many times longer than it is wide, somewhat like a ribbon. Sometimes it is so narrow as to suggest a line. Ex. grass
A lyrate leaf is pinnately veined with a large rounded lobe at the apex and smaller lobes towards the base. Ex. white oak
An orbicular leaf is circular. Ex. dewdrop, water pennywort
An ovate leaf is shaped like an egg, with the broadest part at the base. Ex. ovate-leaf water pennywort
An obovate leaf is shaped like an egg, with the broadest part at the apex. Ex. red clover
A peltate leaf is shield-shaped with the petiole attached to the lower surface. Thus, it resembles a coin balanced on the end of a pencil. Ex. nasturtium
A reniform leaf has the shape of a bean or kidney. Ex. kidney-leaved violet, marsh marigold
A runcinate leaf has sharply cut divisions directed backwards toward the base. Ex. dandelion
A sagittate leaf is triangular, with the two basal lobes pointing downward like an arrowhead. Ex. broadleaf arrowhead
A spatulate leaf is broad and rounded at the apex with the basal end long and tapered. In form it suggests a spatula. Ex. plantain-leaved pussytoes
Leaf Forms
A simple leaf has a blade which occurs as a single unit, although it may be lobed or dissected. Ex. maple, dandelion, lilac
A compound leaf has a blade which is divided into smaller, blade-like parts called leaflets. It is considered only one leaf because it grows from only one bud in the axil of the stem. Ex. locust, hickory, rose
A petiolate leaf has the petiole present. Ex. apple, violet
A sessile leaf has no petiole. The leaf is positioned directly on the stem. Ex. gentian, campion
A sessile leaf is sheathed when the basal portion of the leaf surrounds the stem, enclosing it. Ex. grass
A stipulate leaf has the stipules present. Ex. rose, red clover
An exstipulate leaf has no stipules. Ex. lily, milkweed, goldenrod
The alternate arrangement of the leaves on the stem occurs when one leaf is produced at each node. Ex. rose, beech
The opposite arrangement of the leaves on the stem occurs when two leaves grow from one node on opposite sides of the stem. Ex. beardtongue, maple
The whorled arrangement of the leaves on the stem occurs when more than two leaves are produced at a node. Ex. pipsissewa, woodruff
Compound Leaves
A rachis is the main axis of a compound leaf.
A pinnately compound leaf has leaflets that are attached to both sides of one central rachis. Ex. rose, walnut
A palmately compound leaf has leaflets starting from a common point near the top of the petiole. Ex. horse chestnut, buckeye
Pinnately compound leaves are called paripinnate when they have an even number of leaflets; that is, without a terminal leaflet. Ex. honeylocust, mesquite
Pinnately compound leaves are called imparipinnate when they have an odd number of leaflets; that is, with a terminal leaflet. Ex. ash, walnut
Pinnately compound leaves are called trifoliate when there are only three leaflets. Ex. poison ivy
Pinnately compound leaves are called ternate when there are three leaflets starting from the same point. Ex. clover
Leaf Indentations
A leaf is entire when it has a simple, smooth margin with no division or toothing of any kind. Ex. lilac
A leaf is toothed when it is indented only slightly along the margins. Ex. birch
A leaf is lobed when the margin has deep indentations. Ex. white oak
Kinds of Entire Leaf Margins
A leaf is undulate when the margin winds gradually in and out, that is, more or less wavy. Ex. blunt-leaved milkweed
Kinds of Toothed Leaf Margins
A leaf margin is serrate when the indentations are pointed like the teeth of a saw and directed toward the apex. Ex. beech, birch
A leaf margin is crenate when the indentations are small and rounded with narrow open spaces between them. Ex. ground ivy
A leaf margin is dentate when the indentations are like sharp teeth projecting at right angles to the leaf margin. Ex. bigtooth aspen, holly
Kinds of Lobed Leaves
Leaves are lobed when the indentations extend only halfway to the base or midrib. Ex. English oak, Norway maple
Leaves are parted when the indentations extend more than halfway to the base or midrib. Ex. pin oak silver maple
Leaves are divided when the indentations extend practically all the way to the base or midrib. Leaves that are palmately divided are also called palmatifid. Leaves that are pinnately divided are also called pinnatifid. Ex. tall coneflower, birdfoot violet
Leaves are dissected when they are cut into more or less fine divisions. Ex. wild carrot, yarrow
Leaves are pinnately lobed when the direction of the indentations is toward the midrib. Ex. oak
Leaves are palmately lobed when the direction of the indentations is toward the base of the leaf. Ex. maple sweetgum
The root generally grows underground and bears no leaves or flowers. It grows downward and takes in water and dissolved minerals from the soil. It fixes the plant to the ground.
The root tip is the actively growing part of the root.
A root hair is an extended portion of a single root cell. They form behind the tip of the root and aid the root in absorbing water and dissolved minerals from the soil.
The root cap is a thimble-like group of cells which fits over the root tip and protects it.
The primary root is the main root.
The secondary roots are the lateral branches of the primary root. They grow horizontally or sometimes obliquely from the primary root. They are generally smaller than the primary root.
Types of Roots
See our detailed lesson and worksheets on Types of Roots.
A tap root is a primary root that enlarges and grows downward. It may produce branches but it remains much larger than the secondary roots. Ex. oak, carrot, dandelion
An adventitious root is one that develops from a stem or leaf of a plant.
A bunch of fibrous roots are generally thin and similar in size. In a fibrous root system the primary root has degenerated and been replaced by numerous adventitious roots. Ex. grass
An aerial root is an adventitious root that grows above the ground. It often attaches the stem of a plan to a solid support. Ex. poison ivy, English ivy
A prop root is an adventitious root that develops from one of the first few stem nodes above the ground and grows downward into the soil. It helps to support the plant. Ex. corn, banyan
Shapes of Roots
A fusiform root is one that tapers at each end in the shape of a spindle. Ex. sweet potato
An obconical root is one that is broad at the stem end and gradually tapers toward the tip. Ex. carrot
A spheroidal root is one shaped like a sphere. Ex. beet
A tuberous root is one which is swollen and enlarged for storage. Tap roots may be tuberous (sugar beet), and fibrous roots may have tubers.
A turbinate root is one which is top-shaped, large and round in the upper part and tapering abruptly in the lower part. Ex. turnip
The Stem
Stem (Parts of the Stem)
The stem generally grows above the ground. It bears branches, leaves, buds, flowers, and fruit, and connects these with the root. The tip or apex is called the growing point.
The node is the point of attachment of a leaf or leaves on the stem.
The internode is the portion of the stem between the successive nodes.
A bud is the beginning growth of a stem or a branch, together with the enclosing scale leaves that protect it. All growth of stems, foliage branches, and flower-bearing shoots occurs from buds.
The axil is the angle between the upper side of a leaf and the stem. A bud is located in an axil.
The xylem is the part of the plant which usually carries water and dissolved minerals upwards from the roots to the leaves.
The phloem is the part of the plant which carries manufactured food downward to places of use or storage in the plant.
The cambium is a layer of cells (meristem) between the xylem and the phloem. During each growing season these cells produce a layer of woody material (mostly xylem) on their inner side toward the center of the stem or root and a layer of bark (mostly phloem) on the outer side.
Types of Stems
An aerial stem grows above the ground.
A subterranean stem grows beneath the surface of the ground.
Stems are called herbaceous when they are soft, green, and do not develop much woody tissue. Herbaceous stems usually do not live over from year to year.
Stems are called woody when there is a large development of xylem tissue. This makes the stem hard and fibrous. Woody stems live over from year to year, becoming a little thicker each growing season.
Aerial Stems
An aerial stem is erect when it grows upright without any support.
An aerial stem is procumbent when it trails along the ground.
A stolon is a procumbent stem that grows horizontally along the surface of the ground and typically has relatively long internodes. New plants develop at the nodes. Ex. strawberry
Subterranean Stems
A corm is a thickened underground food-storage stem surrounded by thin papery scalelike leaves. Ex. crocus, gladiolus
A rhizome is a horizontal, underground stem having nodes and internodes. New stems and roots grow from these nodes and internodes. Ex. iris, Bermuda grass
A tuber is a swollen, fleshy internode of an underground stem. It bears a small bud in the axil of a scale-like leaf – the “eye” of the potato. Ex. potato
A bulb is a short, thickened underground stem with a large number of fleshy scaleleaves. The scaleleaves are attached to the stem at a thickened region called the disk. Roots grow downward from the disk. Ex. tulip, onion
The Bud
A bud is a structure on a stem which contains a small mass of growing tissue called the meristem. This mass contains tiny rudimentary leaves, nodes, and internodes. A bud can be considered a much shortened compact, undeveloped section of stem.
The meristem is a mass of growing tissue. The cells located here are capable of frequent cell division, and therefore are responsible for the first phase of growth.
A bud is naked when the growing tissue and the rudimentary leaves are exposed to the air. Most herbaceous plants have naked buds.
When present, bud scales are small, dry scale-like leaves that cover and protect the bud. Most woody plants have buds covered by bud scales.
An axillary bud is located in the angle (axil) between the leaf and the stem. Axillary buds may become branches or they may develop into flowers.
A terminal bud is located at the tip of a stem. It extends the length of the stem during the growing season.
A mixed bud produces twigs bearing both new leaves and flowers. Ex. buckeye, apple
A flower bud is a growing point which forms a flower.
A foliage bud produces branches, which in turn bear leaves.
The flower consists of four whorls or groups of modified leaves: those forming the calyx, those forming the corolla, those forming the stamens, and those forming the pistil.
The calyx is the outer whorl of the flower. It is made up of sepals. The calyx commonly serves as a cover preventing loss of water from the developing flower parts.
The corolla is the whorl of the flower and is composed of petals. Commonly the petals are colored, attracting insects to nectar glands on or near their bases.
The stamens are the male parts of the flower and produce the pollen.
The pistil is the central, female part of the flower and produces the ovules, which mature into seeds. It consists of one or more transformed leaves which fold together to form closed receptacles called carpels. A simple pistil consists of one carpel and a compound pistil of two or more fused carpels.
The receptacle is the tip of the floral twig, from which the floral parts grow.
The perianth is a collective term for the sepals and petals of the flower.
The axis is the imaginary line of the floral stalk along which the flowers are arranged.
Flower Variations
A flower is complete when all the parts (sepals, petals, stamens, and pistil) are present.
A flower is incomplete when one or more parts are missing. Such a flower may lack all or part of the perianth, or either stamens or pistils.
A flower is perfect when it has both stamens and a pistil.
A flower is imperfect when it lacks either stamens or pistils.
An imperfect flower is staminate when it has only stamens. Ex. hickory, maple, sassafras
An imperfect flower is pistillate when it has only one or more pistils. Ex. hickory, maple, holly
The floral parts of a flower are petaloid when they are flattened and colored, and look like petals.
Flower Symmetry
A flower has radial symmetry when the sepals and/or petals radiate from the center of the flower. Any line passing through the center of the flower will divide it into two like halves. Ex. apple, rose, sunflower
A flower has bilateral symmetry when the sepals and petals are arranged in such a way that only one line passing through the center of the flower will produce two like halves. Ex. pea, orchid, mint, snapdragon
Forms of Flower Parts
The parts of the flower are called distinct if they are separate or free from each other.
If the same floral parts, for example, the petals, are united or fused to one another, they are called coalescent. Coalescent floral parts can also be called connate.
Different floral parts, such as the petals and the stamens, are adnate if they are fused to one another.
The prefix apo- is used to describe plant parts that are free or distinct. The rose is apopetalous because the petals of the rose are free. The butter cup is aposepalous because the sepals are free. The larkspur is apocarpous because the carpels are free.
The prefixes syn- or sym- are used to describe plant parts that are fused together. The bellflower is sympetalous because the corolla tube consists of fused petals. The pea is symsepalous because the calyx tube consists of fused sepals. The lily is syncarpous because the carpels are fused.
Forms of Distinct Corollas
A flower is cruciform when the corolla has four separate petals in the form of a cross. Ex. mustard
A flower is papilionaceous when the petals of the corolla are separate and take the form of a butterfly. Ex. pea
A flower is rotate when the petals of the corolla are separate and are spread out like the spokes of a wheel. Ex. geranium, storksbill, apple, wild rose
Parts of the Coalescent Corolla
The tube is the cylindrical portion at the base of a sympetalous flower.
The throat is the opening at the top of the tube of a sympetalous flower.
The limb is the spreading uppermost portion of the corolla.
Forms of Coalescent Corollas
A flower is tubular when the petals of the corolla are united into the form of a tube with short limbs. Ex. thistle
A flower is funnelform when the petals of the corolla are funnel-shaped, with the tube gradually widening into the limbs. Ex. jimsonweed
A flower is rotate when the petals of the corolla are wheel-shaped, with a short tube and wide limbs at right angles to the tube. Ex. borage, forget-me-not
A flower is salverform when the petals of the corolla are trumpet-shaped, with a long slender tube and rotate limbs, spread out like the spokes of a wheel. Ex. phlox
A flower is ligulate when the petals of the corolla are united into a shape resembling a tongue or strap. Ex. a floret of the dandelion
A flower is campanulate when the petals of the corolla are united into a bell shape. Ex. harebell
A flower is labiate when it has an irregular corolla of five petals resembling open lips, with the upper lip being formed by the fusion of two petals and the lower lip being formed by the fusion of three petals. Ex. salvia, mint
A flower is urceolate when the petals of the corolla are united and urn-shaped, forming an expanded tube that is constricted at the throat. Ex. bearberry, blueberry
A flower is saccate when the petals of the corolla are united to form a pouch. Ex. lady-slipper
A flower is galeate when the perianth is fused to form a hood. The flower is helmet-shaped. Ex. snapdragon, monkshood
Special Flowers
A spur is a hollow, tubular projection of the perianth. It can be formed from a sepal as in the larkspurs or from a petal as in the columbines. Ex. larkspur, columbine
A keel is a portion of the perianth that is ridged like the bottom of a boat. The lower two coalescent petals of the pea family are keeled. Ex. pea
A galea is a hood formed from a portion of the perianth. In the snapdragons it is formed from two upper petals. In the monkshood it is formed from the upper sepal. Ex. snapdragon, monkshood
The Stamen
The stamen is the male part of the flower and produces the pollen.
The filament is the stalk-like part of the stamen.
The anther is the part of the stamen where the pollen is produced. It is found at the top of the filament.
The pollen is the fine, dust-like substance produced in the male sex cells of the plant. Each grain of pollen consists of a single male cell.
Variations of the Stamens
The stamens are monadelphous when the filaments are fused into one bundle. Ex. hollyhock, squash
The stamens are diadelphous when they are divided into two bundles. Usually one bundle consists of stamens with fused filaments and the other bundle is a single free stamen. Ex. pea
The stamens are synantherous when the anthers are fused.
The stamens are epipetalous when their filaments are fused to the petals. Ex. borage, gilia, phlox
The Pistil
The pistil is the central, female part of the flower and produces the ovules, which mature into seeds. It consists of one or more transformed leaves which fold together to form closed receptacles called carpels. A simple pistil consists of one carpel and a compound pistil of two or more fused carpels.
The ovary is the enlarged, basal portion of the carpel or pistil that contains the ovules. The ovary develops into the fruit.
The style is the elongated portion of the carpel connecting the stigma and the ovary.
The stigma is the part of the pistil, usually the apex, which receives the pollen. Its surface is usually sticky with a sugar solution in which the pollen grains germinate.
Position of the Ovary
The superior ovary is attached to the receptacle above the attachment of the other floral parts.
The inferior ovary lies below the attachment of the other floral parts and is embedded in the receptacle.
The half-inferior ovary is partially embedded in or surrounded by the receptacle.
A perigynous flower is one where the sepals, petals, and stamens are attached around the pistil, forming a floral cup. In perigynous flowers, the floral cup is free from the ovary.
An epigynous flower is one where the sepals, petals, and stamens are attached above the pistil, forming a floral cup. In epigynous flowers, the floral cup is adnate (fused) to the ovary.
A hypogynous flower is one where the sepals, petals, and stamens are attached below the ovary. There is no floral cup but only a simple receptacle.
A flower is solitary if it occurs single on a peduncle, the main supporting stalk of the flower.
A flower is terminal if it is solitary and occurs single at the apex of a main stem or branch. Ex. tulip
A flower is axillary when it terminates a small lateral branch occurring in the axil of a leaf along the stem. Ex. pansy
The inflorescence is the flowering area or segment of the plant. It includes an arrangement of one or more flowers on a floral axis.
Parts of an Inflorescence
The peduncle is the main supporting stalk of the whole inflorescence.
The rachis is the central axis of the inflorescence.
The pedicel is the supporting stalk of an individual flower in an inflorescence.
Types of Inflorescences
A spike is a collection of flowers produced from a common stalk, where the flowers rest directly on the rachis without pedicels to attach them.
A raceme is a collection of flowers produced from a common stalk, where the flowers are attached to the rachis by pedicels. The lower flowers bloom first and eventually the terminal bud forms the last flower. Ex. hyacinth, foxglove, snapdragon
A corymb is a flat-topped cluster of flowers produced from a common stalk. The pedicels of the lower flowers are longer, and those of the upper flowers are gradually shorter. The flowering sequence begins with the outer flowers. Ex. goldenrod, candytuft
A panicle is a cluster of spikes, racemes, or corymbs. It is a compound inflorescence. Ex. oats, yucca
A cyme is a collection of flowers forming a flat-topped, branched, inflorescence. The flowering sequence begins with the terminal flower at the top or in the center of the flower cluster. Ex. buttercup, borage, cinquefoil
An umbel is a collection of flowers produced from a common stalk, where the rachis is greatly contracted. The pedicels appear to spring from the same point and are all of equal length like the ribs of an umbrella.
A compound umbel is a collection of flowers produced from a common stalk, where each pedicel bears a smaller or secondary umbel. Ex. parsley, carrot, dill
A head or capitulum is a collection of flowers produced from a common stalk, where the flowers are sessile (without pedicels) on a compound receptacle. The marginal flowers bloom first, the central flowers last. Ex. daisy, dandelion
A spadix is a pike with a fleshy or succulent rachis. The flowers are often embedded in the rachis. This is usually enclosed by a large leaf called a spathe. Ex. calla
A catkin or ament is a spike crowded with small flowers having no petals. Catkins are the male flowers of oak, walnut, sweet chestnut, willow, poplar, and birch.
The Fruit
Parts of the Fruit
A fruit is the ripened ovary or ovaries of a seed-bearing plant. Its function is to protect and help disperse the enclosed seeds.
The pericarp is the wall of the ripened ovary or fruit. In many fruits, particularly those that are fleshy, this wall can be divided into three distinct layers.
The exocarp is the outer layer of the wall, usually corresponding to the peel.
The mesocarp is the middle layer of the wall, corresponding to the fleshy part of a peach, cherry, or plum.
The endocarp is the inner layer of the wall, usually corresponding to the stone of a plum or peach.
The locule is the seed chamber of the fruit.
The seed is the ripened ovule contained within the locule of the fruit.
A simple fruit is derived from a single pistil that may be simple or compound. These are by far the most common and diverse fruits. When ripe they may be soft and fleshy, or dry and woody or papery. Ex. blueberry, acorn, iris
An accessory fruit is one in which additional floral parts are retained as the ovary matures. The edible fleshy portion of the apple is made up of stem and floral cup. The core of the apple is the ovary. Ex. apple, pear
A fruit is aggregate if it is derived from a single flower in which there is more than one carpel or ovary, each giving rise to a fruitlet. The fruit consists of an aggregation of fruitlets. Ex. raspberries, blackberries
A fruit is accessory aggregate when it is derived from a single flower with more than one carpel and when the bulk of the fruit is made up of non-ovarian tissue. The bulk of the strawberry, for example, is made up of the receptacle of the flower.
A fruit is multiple when it is derived from the ovaries of several flowers which fuse on a common rachis. Ex. pineapple, mulberyy
A fleshy fruit has some portion or the whole of the pericarp that is juicy and edible.
A dry fruit has a pericarp that is hard and dry.
Types of Fleshy Fruits
A berry is a fruit in which the whole of the pericarp is soft and succulent. There are usually several to many seeds. Ex. grape, currant, blueberry
A drupe is a fruit in which the exocarp and the mesocarp are succulent, but in which the endocarp is extremely hard. It usually encloses a single seed. Ex. cherry, plum, apricot, walnut
A hesperidium is a segmented berry with a tough, leathery exocarp. The bulk of the fruit is derived from glandular hairs along the locule wall. Ex. orange, grapefruit, lemon
A pepo is a hard-rinded berry belonging to the gourd family. Ex. pumpkin, melon, cucumber
A pome is a simple accessory fruit in which the fleshy part and the skin are formed from the floral cup. Embedded in it is the cartilaginous pericarp enclosing the seeds.
Kinds of Dry Fruits
A fruit is dehiscent when the pericarp bursts open to allow the seed to escape.
A fruit is indehiscent when the pericarp does not burst open to allow the seeds to escape.
Types of Dehiscent Dry Fruits
A capsule is a dry fruit, usually many-seeded and composed of two or more carpels which may open by pores, valves, or teeth. Ex. poppy, lily, foxglove, violet
A follicle is a fruit derived from a single carpel and dehiscing along a single line. Ex. milkweed
A legume is a fruit composed of a single carpel which dehisces along two sides. Ex. pea, vetch, bean, clover
A silique is an elongated capsule formed from two carpels, and having a false partition lengthwise. The two walls of the fruit separate, opening from the base upwards, and remaining attached at the apex. Ex. wallflower, rape, mustard
Types of Indehiscent Dry Fruits
An achene is a small, indehiscent, one-seeded fruit with a hard pericarp that is free from the seed. Ex. sunflower, buttercup
A caryopsis or grain is a small, one-seeded fruit with the pericarp fused with the seed. Ex. corn, grass, wheat
A nut is a large, one-seeded fruit derived from a compound ovary and having a woody pericarp. Ex. acord
A samara is an achene with a wing – a long, thin, flat structure developed from a portion of the ovary wall. Ex. elm, ash, maple
The seed of a flowering plant is the fertilized and ripened ovule. It contains an embryo and is covered by a protective seedcoat.
The testa is the hard external coating of the seed which encloses and protects the embryo.
The cotyledon or seed leaf is an embryo leaf in the seed that usually either stores or absorbs food.
The embryo is the miniature plant before the beginning of its rapid growth. It is the “germ” of a seed and will develop into a root, stem, and leaf of a full-grown plant.
The plumule is the part of the embryo which will form the shoot – the stem and leaves of the new plant.
The radicle is the part of the embryo which will form the root of the new plant.