PLANTS AND PEOPLE PLANTS AND PEOPLE Biology – 328 Biology – 328

Lab 4 – Major Families ILab 4 – Major Families I

ObjectiveTo 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 fineFlowers - Umbellate inflorescence

(pedicel arises from a common point) Fruits - Schizocarp (dry fruit that

splits at maturity into two or more closed, one-seeded 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 familyFlowers 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 pistil

Drupelet/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 labQuiz Field Trip: Mid-valley cotton gin