Lab 5: Monocots 2 and Poales Flashcards
What are the common names for Cyperaceae, Juncaceae, and Poaceae?
Cyperaceae: sedges
Juncaceae: rushes
Poaceae: grasses
“Sedges have edges, rushes are round, grasses are hollow right down to the ground”
What are some general identification characteristics of Poaceae?
2-ranked leaves, stem round and hollow, open sheaths, ligules
What type of fruit does Poaceae produce?
Caryopsis (or grain) with the pericarp fused to the seed coat
Poaceae floral characteristics
Most grass florets are perfect
3 stamens
Compound ovary formed from two fused carpels
Perianth is reduced to 2 tiny scales called lodicules which are at the base of each floret (almost always bisexual, but some unisexual)
What is the basic unit of the inflorescence of a grass called?
spikelet (contains one or many florets)
What are the parts of a grass floret?
- Upper and lower glume (bracts)
- Lemma: outer bract on the floret
- Palea: inner bract on the floret
- Awn: stiff, narrow, pointed structure that some species of grass have on either the tips or backs of one of their glumes or lemmas
- Anther
- Filament
- Stigma
- Ovary (matures into a grain/caryopsis)
What is a ligule?
Small appendage attached to the leaf
What is a auricle?
Small, clasping outgrowths that may or may not be present on the leaf collar
How are spikelets attached to the grass culm (a grass stem)?
Can be directly attached (sessile) or attached on short pedicels (pedicellate spikelets)
Phalaris arundinacea (Poaceae family)
Each floret has 1 lemma and 1 palea
Filament: stringy structure with no rigidity
3 stamens
2 stigmas = 2 carpels (bi-carpelate flower)
Spreads via seeds or pieces of stem, roots, and rhizomes
The spikelets are borne on stalks or on branches
- the spikelets are mainly carried at the end of the stem
the lemma has no awn
What are some identification traits of Cyperaceae (genus Carex)?
3-ranked leaves, stems mostly triangular shaped, usually closed sheaths, unisexual flowers, spikes can be unisexual/mixed
Carex floral parts
- 3 stamens
- ovary resulting from the fusion of 2-3 carpels
- Florets usually subtended by only a single bract (called a scale)
- arrangement of florets and scales can be in 2-ranks or spirally arranged
- Flowers are unisexual
-Style protrudes from the perigynium and splits into 2 or 3 stigmas that stick out to catch pollen - no petals/sepals
What is the perigynium in Carex?
sac-like bract that surrounds the ovary in the female (carpellate) flowers
What type of fruit do Carex produce?
Achenes
What species of Carex did we key out in lab?
Carex lupulina
