Utah Flora
BOT2100
Lecture 1
Floral Morphology
Floral – reproductive parts of a plant
Including:
Inflorescence
Flowers
Fruits
Utah Flora
Floral Morphology
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Perianth – the calyx and corolla of a flower, collectively
Calyx – the outer whorl, all of the sepals of a flower
Sepals – the segments of a calyx
Corolla – the inner whorl, all of the petals of a flower
Petals – the segments of a corolla, usually colored
Utah Flora
Floral Morphology
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Calyx
Sepals
Corolla
Petals
Sepals
Utah Flora
Floral Morphology
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tepals – the segment of a perianth which is not differentiated into
a sepal or a petal
apetalous – without petals
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Floral Morphology
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Regular –radially symmetrical
Actinomorphic – another term that means: radially symmetrical
Free – separate, not attached
Distinct – another term that means: separate, not attached
Petals
5-merous
Utah Flora
Floral Morphology
Regular –radially symmetrical
Fused – fusion of like parts
Connate – another term that means: fusion of like parts
Petals
5-lobed
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Utah Flora
Floral Morphology
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Irregular – billaterally symmetrical
Zygomorphic – another term that means: billaterally symmetrical
Fused – fusion of like parts
Petals
5-lobed
2- lipped
Utah Flora
Floral Morphology
Irregular
Zygomorphic
Fused
Petals
5-lobed
2- lipped
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Utah Flora
Floral Morphology
Irregular
Zygomorphic
Free
Papilionaceous – irregular corolla
of a pea, with a free banner, two
free wing petals, and two fused
keel petals
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Utah Flora
Floral Morphology
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Androecium – all of the stamens in a flower, collectively
Stamens – the male reproductive organ of a flower
Anther – the expanded, apical, pollen bearing portion of the stamen
Filament – the stalk of the stamen
Utah Flora
Floral Morphology
BOT2100
Androecium – all of the stamens in a flower, collectively
Stamens – the male reproductive organ of a flower
stamens more than twice the
number of the petals
stamens 10, or exactly twice the
number of petals
Utah Flora
Floral Morphology
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Staminode – a modified stamen which is sterile
Stamens
Stamens less than twice the
number of the petals (or lobes)
Stamens 4, Staminode 1
Staminode
Utah Flora
Floral Morphology
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Gynoecium – all of the pistils in a flower, collectively
Pistil – the female reproductive organ of a flower
Stigma– the apical portion of the pistil which is receptive to pollen
Style – the narrowed portion of the pistil
Ovary – the basal portion of the pistil that contains ovules (seeds)
Utah Flora
Floral Morphology
BOT2100
Carpels – a leaf modified into a pistil,
another term for the stigma, style,
and ovary of a plant
Monocarpous – a flower with one carpel (or pistil)
Apocarpous – a flower with two or more separate
carpels (or pistils)
Syncarpous – a flowers with two or more fused carpels
(or pistils)
Utah Flora
Floral Morphology
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Superior
– flowers with the stamens, petals, and sepals attached
•
below the ovary
Hypogynous – an alternate term for superior
Inferior – flowers with the ovary beneath the point of attachment
of the stamens, petals and sepals
Epigynous – an alternate term for inferior
Perigynous – flowers with the stamens, petals and sepals borne
on a calyx tube (hypanthium) surrounding but not
fused to the superior ovary
Hypanthium – a cup shaped expansion of the floral axis formed
from the union of the basal parts of the calyx and
corolla
Utah Flora
Floral Morphology
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Hypanthium
(purple region)
Inferior
Superior
red parts are the calyx (sepals)
purple parts are the corolla (petals)
yellow parts are anther
green parts are ovaries
Utah Flora
Inflorescence
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Complete – a flower with all of the typical parts: sepals, petals,
stamens and pistils.
Perfect – a flower with both female (pistils) and male (stamens)
reproductive organs
•
Utah Flora
incomplete – a flower lacking one or more
of the typical parts: sepals, petals,
stamens and pistils.
imperfect – a flower with either stamens or
pistils, but not both
unisexual – alternate term for imperfect
pistillate – a flower with pistils and lacking
stamens
dioecious – a plant with imperfect
flowers, the staminate and pistillate
flowers borne on separate plants
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Utah Flora
Floral Morphology
incomplete
imperfect
unisexual
dioecious
staminate– a flower with stamens and
lacking pistils
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Utah Flora
Floral Morphology
incomplete
staminate
imperfect
unisexual
monoecious – a plant with imperfect
flowers, the staminate and pistillate
flowers borne on the same plant
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pistillate
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Inflorescence
•
flowering part of a plant, collectively
•a
•
cluster of flowers
the arrangement of the flowers on the
flowering axis
Utah Flora
Inflorescence
Rachis – the main axis of an inflorescence
Pedicel – the stalk of a single flower in an
inflorescence
Pedicillate – a flower with a pedicel
Peduncle – the stalk of a solitary flower or
the stalk of an inflorescence
Pedunculate – a inflorescence with a peduncle
Sessile –
This plant has sessile flowers
with a pedunculate inflorescence.
Each inflorescence has a rachis.
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Utah Flora
Inflorescence
Terminal – a flower at the tip or apex
This plant has solitary,
pedunculate flowers.
Each flower is terminal.
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Utah Flora
Inflorescence
Bracts – a reduced leaf at the base of a flower
or inflorescence
Axillary – a flower arising in the axil of a leaf
This plant has bracteate, sessile flowers
This plant has axillary, pedicillate flowers
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Utah Flora
Inflorescence
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Solitary – an inflorescence with a single flower
Utah Flora
Inflorescence
Spike – an unbranched, elongate inflorescence
with sessile flowers
Spicate – a plant with a flowers arranged in a
spike
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Utah Flora
Inflorescence
Raceme – an unbranched, elongate
inflorescence with pedicillate flowers
Racemose – a plant with a flowers arranged in
a raceme
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Utah Flora
Inflorescence
Panicle – an branched, racemose inflorescence
Paniculate – a plant with a flowers arranged in a panicle
panicles can remembered as:
a raceme
of
racemes
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Utah Flora
Inflorescence
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Umbel – an inflorescence with the pedicels arising from a more or less
common point, like an umbrella
Compound Umbel – an umbel of umbels
Umbellate – a plant with a flowers arranged in a umbel
rounded, compound umbel
flat, compound umbel
Utah Flora
Inflorescence
Cyme – a flat-topped (or rounded)
inflorescence in which the terminal flower
blooms first
Cymose – a plant with a flowers arranged in
a cyme
This is a raceme of cymes, several cymes
are located at each node of the inflorescence
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Utah Flora
Inflorescence
terminal
not terminal,
this can keep
expanding
Scorpioid cyme – an inflorescence shaped
like a scorpion’s tail in which the
terminal flower blooms first and the
axis elongates in a zig-zag fashion
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Utah Flora
Inflorescence
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Capitate or Head-shaped – a dense, many-flowered inflorescence,
generally terminal
Verticel – a dense, many-flowered inflorescence at a node, whorled
capitate verticels
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Inflorescence
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Composite, Involucrate
ray
a many flowered head
phyllary (each leaf-like bract)
involucre (not a calyx)
ray
13-14 flowers
receptacle
(inside involucre)
disk
many
flowers
Utah Flora
Fruit
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Legume – a dry, dehiscent fruit derived from a single carpel,
opening along two lines of dehiscence
Loment – a legume with constrictions between the seeds,
sometimes breaking into 1 seeded segments
Follicles – a dry, dehiscent fruit derived from a single carpel and
opening along a single line
Capsule – a dry, dehiscent fruit derived of more than one carpel
Silique – a dry, dehiscent fruit in Brassicaceae, less than twice as
long as wide (circular)
Silicle – – a dry, dehiscent fruit in Brassicaceae, more than twice as
long as wide (tubular)
Utah Flora
Fruit
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Achene – a dry, indehiscent fruit derived from a single carpel with
a single seed attached to the ovary wall at a single point
(sunflower)
Caryopsis – a dry, indehiscent fruit derived from a single carpel
with a single seed fused to the ovary wall (cereal grains)
Samara – a dry, indehiscent fruit with wings
Nut – a dry, hard, indehiscent fruit with a single seed
Nutlet – a dry, hard, indehiscent fruit with a 2 to 4, one-seeded
lobes
Schizocarp – a dry, hard, indehiscent fruit which plits into 2 to
many, one-seeded segments
Utah Flora
Fruit
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Berry – a fleshy fruit derived from a single carpel with many seeds
(tomato)
Drupe – a fleshy, indehiscent fruit derived from a single carpel
with one hard central seed (called a stone; peaches, cherries)
Pome – a fleshy, indehiscent fruit derived from an inferior ovary
composed of many fused carpels (apple)
Aggregate – a fleshy fruit derived from multiple, separate carpels
in a single flower (raspberry)
Multiple – a compound fruit formed from many, separate flowers
crowded along a central axis (pineapple)
Cone – called a strobilis, or cone-like cluster of seed-bearing bracts
crowded along a central axis (sometimes woody; pine cones)
Utah Flora
BOT2100
Assignment
•Draw and label all flower and fruit samples provided in lab
•Make sure to label the peduncle, pedicel, corolla, petals, calyx,
sepals, phyllaries, ray flowers, disk flowers, stamens, stigma
(not all may have these features readily visible or present)
•Identify whether the flower is solitary, a raceme, a spike,
a panicle, a cyme, or an involucre
•Identify whether the fruit is a cone, a legume, a samara, or
a capsule (the 4 types we have for examples)
•Split open the Penstemon flower and illustrate the stamens,
filaments, staminode, stigma, style, ovary, corolla, and calyx
•See Harris & Harris 175-178 for floral diagrams