Download CHAPTER 7 DIVERSITY AND CLASSIFICATION OF FLOWERING

CHAPTER 7
DIVERSITY AND CLASSIFICATION OF FLOWERING PLANTS:
AMBORELLALES, NYMPHAEALES, AUSTROBAILEYALES, MAGNOLIIDS, CERATOPHYLLALES, AND
MONOCOTS
REVIEW QUESTIONS
GENERAL
1. What is the Angiosperm Phylogeny Group system of classification and what ranking does it utilize?
The APG system of classification is one utilizing molecular studies or a combination of morphologycal and molecular
data to classify angsiosperms. The APG III system classifies one to several families into orders (thus, each group
having the ending “-ales”), where strong evidence suggests that the order is monophyletic.
2. What are the major groups of “basal” angiosperms?
Amborellales, Nymphaeales, Austrobaileyales, Chloranthales, Magnoliids (consisting of Laurales, Magnoliales,
Canellales, and Piperales).
3. Why have the traditional “dicots” been abandoned as a taxonomic group?
They are now known to be paraphyletic.
4. What is a floral formula? What are the symbols used in floral formulas?
a) A shorthand used to summarize the number and fusion of floral parts.
b) P=Perianth parts; K=calyx; C=corolla; A=androecium; G=gynoecium.
5. What is a floral diagram and what does it represent?
Floral diagrams represent a diagrammatic cross-sectional view of a flower bud, showing the relative relationship of
perianth, androecial, and gynoecial components, as well as things such as stamen position, placentation, and perianth,
calyx, or corolla aestivation.
NONMONOCOT GROUPS
6. Name the family and species of what is currently thought to represent the most basal lineage of angiosperms.
Amborellacae; Amborella trichopoda.
7. Name the diagnostic characteristics of the Amborellaceae. Do these necessarily represent ancestral angiosperm features?
a) Vessel-less, evergreen shrubs with unisexual flowers having an undifferentiated, spiral perianth, numerous,
laminar stamens, and an apocarpous, apically-open gynoecium, with 1-ovuled carpels.
b) Not all may represent ancestral features.
8. How does the Nymphaeales compare with the Amborellaceae in: plant habit, flower sex, perianth arrangement, stamen
number and type, gynoecial fusion type, and ovary position?
Plant habit: herb vs. shrub.
Flower sex: bisexual vs. unisexual.
Perianth arrangement: usually dichlamydeous, parts spiral vs. undifferentiated, parts spiral.
Stamen number: 3, 6, or numerous vs. numerous.
Stamen type: laminar to filamentous vs. laminar.
Gynoecial fusion type: syncarpous or apocarpous vs. apocarpous.
Ovary position: inferior or superior vs. superior.
9. What anatomical feature is characteristic of the family Illiciaceae? How is this family different from and similar to the
Amborellaceae and Nymphaeales?
a) Have ethereal oil cells.
b) The Illiciaceae are distinctive in being evergreen trees or shrubs having aromatic oil cells, with glabrous, spiral,
pellucid-punctate, exstipulate leaves, the flowers with numerous, spiral tepals (outer sepal-like, inner petal-like), fewnumerous stamens, and few-numerous, one-seeded, apocarpous pistils in a single whorl, the fruit a follicetum.
10. For the Ceratophyllaceae name the plant habitat, plant habit, leaf arrangement and morphology, and economic
importance.
Plant habitat: aquatic (floating or submerged).
Plant habit: herb.
Leaf arrangement: whorled.
Leaf morphology: 1-4-dichotomously divided, serrulate.
Economic importance: aquarium plant and as a protective cover in fisheries.
11. What distinctive anther dehiscence occurs in the Lauraceae?
Valvular.
12. Name two economically important members of the Lauraceae.
Laurus nobilis, laurel/bay; Cinnamomum cassia, cassia/cinnamon.
13. Name at least two families of the Magnoliales.
Annonaceae, Magnoliaceae.
14. For the Annonaceae, what is distinctive about the leaf arrangement and endosperm structure?
a) Distichous.
b) Ruminate.
15. What is distinctive about the receptacle and gynoecial fusion of the Magnoliaceae?
Receptacle elongate. Gynoecial fusion apocarpous.
16. What is the fruit type of the Magnoliaceae?
Aggregate fruit of follicles, berries, or samaras.
17. Name at least three families of the Piperales.
Aristolochiaceae, Piperaceae, Saururaceae.
18. What is the etymology of “Aristolochia”?
Gr. aristos, best + lochia, childbirth, from resemblance of a species of Aristolochia to the correct fetal position.
19. What are the diagnostic features of the Aristolochiaceae?
The Aristolochiaceae are distinguished in being usually climbing plants, having an enlarged, petaloid calyx, an absent
to reduced corolla, often adnate stamens (forming a gynostemium), and an inferior to superior, 3–6-carpeled and
loculed ovary.
20. How does the Piperaceae differ from the Aristolochiaceae?
The Piperaceae are distinctive in having an atactostelic stem, a spike or spadix with numerous, very small, unisexual
or bisexual flowers lacking a perianth, the ovary solitary, 1-ovulate, the fruit a 1-seeded berry or drupe.
P 0 A 3+3 [1–10] G 1 or (3,4), superior.
21. What is an economically important member of the Piperaceae?
Piper nigrum, black pepper; Piper methysticum, kava.
22. How does the Saururaceae differ from the Piperaceae?
The Saururaceae differ in having a bracteate spike or raceme, the ovary many-ovulate, the fruit a capsule.
P 0 A 3, 3+3, or 4+4 G (3–5), superior.
MONOCOTS: BASAL LINEAGES
23. Name and describe the major apomorphies of the monocots.
Atactostelic stem-numerous, apparantly scattered vascular bundles.
Leaf venation parallel (primitively).
Embryo with one cotyledon.
Cuneate, proteinaceous, sieve tube plastids.
24. Name the order, family, and genus of the most basal lineage of monocots.
Acorales, Acoraceae, Arocus.
25. How does Acorus differ from the Araceae in: leaf structure; seed nutritive tissue; crystal type?
Leaf structure: leaves distichous, unifacial, ensiform. Araceae leaves spiral or distichous, bifacial, gen. not ensiform.
Seed nutritive tissue: perispermous and endospermous. Araceae endospermous.
Crystal type: Lacks raphide crystals. Araceae have raphide crystals.
26. What is the leaf venation of members of the Araceae?
Parallel, penni-parallel, or netted.
27. What is the inflorescence type of the Araceae?
A spadix, subtended by an often showy spathe. (Reduced to 1-4 flowers in a pouch in the Lemnoideae.)
28. Name an economically important member of the Araceae.
Colocasia esculenta, taro.
29. What are two putative apomorphies of the Asparagales? Of the Asparagales minus the Orchidaceae?
a) Simultaneous microsporogeneis; inferior ovary.
b) Phyotmelan-encrusted seed coats.
30. What is a cytological apomorphy of the Agavaceae?
Dimorphic chromosomes: 5 long and 25 short.
31. What is the ovary position of the Agavaceae?
Inferior or superior.
32. What is a chemical apomorphy of the Alliaceae?
Alliin, which is enzymatically converted by wounding to allyl sulfide compounds.
33. Name two economically important members of the Alliaceae.
Allium sativum, garlic; Allium cepa, onion.
34. How are members of the Asphodelaceae distinguished? What is their distribution?
Herbs or pachycaulous trees with leaves usually succulent, flowers trimerous with a superior ovary, and the seeds
arillate.
35. Name and define the leaf structure of the Iridaceae.
Unifacial-having a plane parallel to the stem, or terete.
36. What is the range of inflorescence morphology of the Iridaceae?
A terminal spike, solitary flower, or a spike or panicle of clusters of 1–many monochasial cymes (often rhipidia),
typically subtended by two spathelike bracts.
37. What is the floral formula of the Iridaceae?
P 3+3 or (3+3) A 3 or (3) G (3), inferior (superior in Isophysis).
38. How many species occur in the orchid family?
Ca. 20,000.
39. For the Orchidaceae, name the ovary position, placentation, and name for specialized androecium.
Ovary position-inferior; placentation-parietal; androecium modified into a pollinarium in all but the Apostasioideae
and Cypripedioideae.
40. What is a gynostemium? What are other names for this structure?
Fusion product of the androecium with the style and stigma.
Also called a column, gynostegium.
41. What orchid is used as a food flavoring and what part of the plant is utilized?
Vanilla planifolia. Fermented fruits (capsules) used.
MONOCOTS: COMMELINIDS
42. Name and describe the major chemical apomorphy of the Commelinid monocots.
UV-fluorescent, cell-wall bound compounds composed of organic acids such as ferulic, diferulic, and/or paracoumaric
acids.
43. Name an apomorphy of the palms.
Plicate leaves.
44. What are the two acceptable scientific names of the palm family?
Arecaceae and Palmae.
45. For the Arecaceae, what is the: flower sex, ovary position, fruit type?
Flower sex: bisexual or unisexual.
Ovary position: superior.
Fruit type: Drupe or berry (rarely dehiscent or a pyrene).
46. What is the seed nutrition of the Commelinid monocots, minus the Arecales and Dasypogonaceae?
Endospermous.
47. Name three apomorphies of the Zingiberales.
Penni-parallel venation, supervolute ptyxis, diaphragmed air chambers, silica cells, inferior ovary.
48. What is the leaf arrangement and plant sex of the Musaceae?
Spiral; monoecious.
49. What is the scientific name of banana?
Musa xparadisiaca.
50. What leaf arrangement apomorphy unites all of the Zingiberales, minus the Musaceae?
Distichous.
51. Name two apomorphies that unite the clade Cannaceae + Costaceae + Marantaceae + Zingiberaceae.
Raphides absent; Fertile stamen one (median posterior), staminodes petaloid.
52. What, in reality, are the showy petaloid structures of this group?
Staminodes.
53. Name two economically important members of the Zingiberaceae.
Zingiber officinale, ginger.
Elettaria cardamomum.
54. What is the specialized anther type of the Cannaceae and Marantaceae?
Unithecal/bisporangiate.
55. Name three families of the Commelinales.
Haemodoraceae, Philydraceae, Pontederiaceae, Hanguanaceae, Commelinaceae.
56. Name one or more apomorphies for these families.
Tannin cells in flowers.
57. Name two apomorphies of the Bromeliaceae.
Twisted styles/stigmas; peltate leaf scales.
58. What is the ovary position of the Bromeliaceae?
Inferior or superior.
59. What special ecological adaptations do various bromeliads have?
Peltate leaf scales function in water absorption.
60. Name an economically important bromeliad.
Ananas comosus, pineapple.
61. What pollen and leaf apomorphies may unite the Cyperaceae, Thurniaceae (including Prionaceae) and Juncaceae?
Pollen in tetrads; leaves tristichous.
62. How do the Cyperaceae and Juncaceae families differ in inflorescence, perianth, and fruit type?
Cyperaceae-inflorescence a sedge spikelet; perianth reduced to bristles or absent; fruit an achene.
Juncaceae-inflorescence of solitary flowers or 1–many cymes, glomerules, or heads; perianth 3+3, scarious; fruit a
loculicidal capsule.
63. How do the Eriocaulaceae and Xyridaceae differ in flower sex? Pollen aperture type?
Eriocaulaceae-flowers unisexual; pollen spiraperturate-spinulose.
Xyridaceae-flowers bisexual; pollen sulcate or inaperturate.
64. What are the two scientific names for the grass family?
Poaceae, Gramineae.
65. How does the leaf arrangement and attachment of grasses differ from that of sedges?
Grasses-distichous, with open-sheathing base and ligules.
Sedges-tristichous, with closed-sheathing base and eligulate.
66. What is the structural difference between a “sedge spikelet” and a “grass spikelet”?
Sedge spikelet-consists of an axis bearing bracts (scales), all or most of which subtend a flower. Flower perianth is
absent or reduced to scales.
Grass spikelet-consists of an axis bearing gen. two basal bracts (glumes) and 1-many florets, each floret a short,
lateral branch bearing a lower, odd-veined lemma, overlapping an upper 2-veined palea, these enclosing a flower,
consisting of 2-3 stamens and/or a 2-3-carpellate pistil with feathery styles/stigmas, the perianth reduced to 2-3
lodicules.
67. What is a: grass spikelet? floret? glume? lemma? palea? lodicule?
Spikelet-inflorescence unit. Glume-one of the gen. 2 bracts at the base of the spikelet. Lemma-larger, lower bract of
floret. Palea-smaller, upper bract of floret. Lodicule-one of modified perianth parts of grass flower.
68. What is the fruit type of the grasses?
Grain/caryopsis.
69. Name the generic and common names of five economically important grain crops.
Avena-oats.
Hordeum-barley.
Oryza-rice.
Secale-rye.
Triticum-wheat.
Zea-corn.
70. Name the characteristics and distribution of the Restionaceae.
The Restionaceae are distinctive in being perennial, rhizomatous, mostly dioecious herbs with photosynthetic erect
stems, leaves reduced to sheaths, an inflorescence of solitary flowers or variously branched spikelets, and small,
unisexual, wind-pollinated flowers with usually monothecal, bisporangiate anthers.
P 3+3 [0–2+0–2] A 3 [1–4] G (3) [1–(2)], superior.
Distributed in the Southern Hemisphere, especially South Africa and Australia.
71. What is the flower sex of the Sparganiaceae and Typhaceae?
Unisexual.
72. How do these two families differ?
Sparganiaceae-inflorescence of unisexual, globose heads (male heads above, female below), fruit drupelike.
Typhaceae- inflorescence a spike (male above and female below), fruit achenelike, dehiscent.