Transcript Slide 1
Biology – 328
PLANTS AND PEOPLE
Lab 4 – Major Families I
Objective
To familiarize you with vegetative and floral
morphology of 8 flowering families
Asteraceae
Apiaceae
Brassicaceae
Cucurbitaceae
Lamiaceae
Liliaceae
Rosaceae
Solanaceae
Asteraceae/Compositae – Sunflower family
Flower - Head inflorescences (inflorescence consists of florets arranged on a common
receptacle)
Florets are composed of a perianth (calyx + corolla), androecium, and gynoecium
Pappus (calyx modified as bristles, awns, scales)
Sympetalous (fused corolla)
Phyllaries or involucral bracts- whorl of green bracts constituting involucre
Synantherous - anthers (5 stamens) united into a tube, bicarpellate (2 carpels) with
one inferior ovary and a two-branched style.
Florets may be
Disk florets- actinomorphic (regular); bisexual; ray or ligulate florets, situated in the
center of a head
Ray florets- zygomorphic (irregular); unisexual-pistillate; with a ligule
Ligulate florets- zygomorphic (irregular); bisexual; with a ligule;
Based on type of florets, a head inflorescence may be a
Discoid head- disk florets only (e.g., Cirsium- thistle)
Radiate head- disk florets in the center; ray florets around the margin (e.g.,
Helianthus- sunflower)
Ligulate head- ligulate florets only (e.g., Pyrrhopappus- false dandelion)
Asteraceae/Compositae – Sunflower family
Apiaceae/Umbelliferae- Carrot and Parsley family
Leaves - Dissected and very fine
Flowers - Umbellate inflorescence (pedicel
arises from a common point)
Fruits - Schizocarp (dry fruit that splits
at maturity into two or more closed, oneseeded parts)
Fruits posses aromatic oils
Apiaceae/Umbelliferae- Carrot and Parsley family
Brassicaceae/Cruciferae - Mustard family
Flowers
Tetradynamous anthers – Out of six stamens, four are long
Fruit
Silique – Made of 2 fused carpels that separate when ripe
Silicle – Smaller and shorter version of silique
Replum - The framework of some pods that remains after the
valves drop off
Brassicaceae/Cruciferae - Mustard family
Lamiaceae/Labiatae-Mint family
Leaf – Opposite leaf arrangement
Flower
Didynamous anthers - Out of four stamens, two are long
Fruit – Cluster of 4 tiny nutlets
Lamiaceae/Labiatae-Mint family
Lilaceae – Onion family
Rosaceae – Rose family
Flowers represent three subfamilies
Subfamily Ovary
Carpels
Fruit
Examples
Prunoideae
Superior
Simple
pistil
Drupe
cherries,
peaches, plums,
nectarines,
apricots,
pluots, almonds
Maloideae
Inferior
2-5
Pome
apples, pears,
quinces.
Rosoideae
Superior
Many simple Drupelet
pistil
/achene
rose hip,
blackberry or
raspberry
Rosaceae – Rose family
Solanaceae – Nightshade, tomato, and
pepper family
Flower
Actinomorphic/regular
Connivent androecium (ends inclined toward each
other)
Poricidal dehiscence (pollen released though pores)
Wandering placenta (Tomato)
Solanaceae – Nightshade, tomato, and
pepper family
CUCURBITACEAE- Cucumber, melon, and
squash family
Flower
Monoecious (male and female in separate flowers but
within the same plant)
Presence of nectary disks in both male and female
flowers
Fruit
Pepo
Parietal placentation
Summary
Today’s Lab
Familiarizing vegetative and floral morphology of
8 flowering families
Next week’s lab
Quiz
Field Trip: Mid-valley cotton gin