Topic 13 - Major flowerless, gymnosperm and monocot talons (identification and importance) Flashcards
Unit in taxonomy
Taxon
Basic unit of biological classification
Species
Species
A group whose members are descended from a common ancestor
Subspecies
Specific geographical distribution or ecological attributes
Variety
No specific geographical distribution, but specific heritable attributes
Form
Noticable morphological deviation with, but inheritance my be doubtful
Nomenclature of cultivated plants
Cultivar
Cultivated botanical variety (provarietas): a group with similar morphology
Cultivated race consists of similar groups of varieties
Higher taxonomic ranks
Species Genus Family -ceae Class -opsida Phylium -phyta
Clade
Consisting of common ancestors and all the lineal descendants
e.g. mosses, ferns, conifers, flowering plants
Algae (divisions)
Phyla of prokaryotes and eukaryotes with ~40-50 000 taxa
Species colonize dried and moist habitats including extreme environmental conditions (e.g. hypersaline lakes, polar sites, geothermal wells)
forms of algae
Uni- or multicellular without tissues and organs that produce oxygen
Algae size
range from µm up to 50-100 meter sized individuals
Importance of algae
supply 60% of world’s oxygen source
Freshwater food webs (phytoplankton) → fishery and fish flour production are based on the organic matter produced by algae
Fixation of atmospheric nitrogen
Dietetic food supply for humans
Forage supply for livestock (protein supply, decreasing rumen acidosis)
Indicators of freshwater quality
Algae poisoning
Waterbloom of drinking water
Mainly caused by cyanobacteria
Neurotoxic alkaloids, hepatotoxic compounds
Poisonings are rare, occurs mainly in summer if there is a heavy water bloom
Ruminant, birds and dogs are susceptible
Lichens
Formerly an individual phylum, currently a group of fungi
A colonial symbiotic organism consists of mycobiont and photobiont
∼13,000 species
About 700 different secondary metabolites, and ∼ 650 occurs only in lichens (lichen acids or lichen substances)
Importance of lichens
Species used as an expectorant
Some species have antibiotic effect → medicinal, veterinarian application
Natural forage (reindeer lichen)
Widely used in cosmetics and paints
Divisions of mosses
Formerly one division → currently divided into three different ones
A transitional group btw. vascular and non-vascular species
The two biggest divisions are mosses and liverworts
No specific veterinarian importance
Major ecological role
Divisions of ferns
First vascular plants with vascular tissues
- clubmosses
- True ferns and horsetils
Rhizome present in both groups
Horsetails
SiO2 crystals in epidermal cells, scale leaves are fused into a sheath, sporangia (an enclosure with spores) at the stem apex
True ferns
Simple or multiply divided leaves, sporangia arranged on the underleaf, dichotomous venetion
Typical poisonous compounds of true ferns
Thiaminase
Ptaquilozide
Division of gymnosperms
First flowering plants
Flowers can be solitary, but generally form cones
Carpels not fused to each other → unenclosed seeds → gymnos (in greek) = naked, sperma (in greek) = seeds
Sperm no longer needs water to fertilise the egg
Cones can be fleshy → cedars, junipers
Several poisonous or medicinal plants
Rarely grazed or nibbled by animals
Major gymnosperm groups
Cycads Ginko tree Yew species Cypress species Pine species
Cycads
Palm-like appearance
With stout and woody stem
Evergreen pinnate leaves
Non-proteinogenic amino acids (neurotoxins) and carcinogenic glycosides
Ginko tree
only one extant dichotomous leaf venetion
Medicinal effects (CNS)
Yew species
Needle-like leaves
Absence of resin ducts
Generally aril covers the seeds
Cypress species
Scale or needle like leaves
Small cones
High proportion of volatile oil → toxic effects may be possible (thujone)
Pine species
Needle-like leaves High proportion of resin Generally large ones Good quality wood Poisonous compounds generally not present
Angiosperms
Flowering plants
Seeds are enclosed by mature ovaries, or fruits
General morphology - angiosperms
Production of fruits
Fibrous root system
Non-branched stem
Modified underground stem occurs generally
Herbaceous stem without secondary growth
Leaves have generally no petiole
Generally six tepals
Araceae
Arum family
Naturally occurs mainly under tropical climate, only a few taxa distributed in Europe
Monosexual and monoecious flowers
Cultivated species (Colocasia esculenta → raw tubers are toxic)
Araceae morphology
Species with creeping stem or epiphytes
Tubers and rhizomes and aerial roots generally occurs
Leaves are shiny and undivided
Flowers are covered with a large bract leaf (insect trap)
fruit = berry
Typical compounds of araceae
Cyanogenic glycosides
Oxalate crystals
Flavonoids
Importance of araceae
Most common plant family of many household plants
Liliales
Order of lillies
Formerly many species were classified into the liliaceae family → now belong to smaller families
Most of the species are cultivated as ornamental plants
Morphology of liliales
Underground stems
Narrow, elliptic leaves
2x3 fused or free tepals with nectar glands
Large conspicuous, colourful flowers
Generally fruit = capsule
Major compounds of liliales
Colchicine (meadow saffron) Sesquiterpene lactons (tulip) Steroidal alkaloids (Veratrum spp.) Steroidal saponins Most of the species has bigger or smaller toxic effect
Juncaceae
Rush family
Species distributed worldwide
Toxic compounds = rare
Juncaceae morphology
Grass-like morphology
Cylindrical stem and leaf with aerenchyma tissue
Generally glamorous species without hairs
Tuft-like appearance
Small, brown, scale-like tepals
Tepals enclose the capsule with dust-like seeds
No spikelet!
Inflorescence bracts can be present
Importance of Juncaceae
Generally low digestibility and nutritive value
Species are used for animal breeding
Planted in garden ponds
Uncertain identification below the genus low
Cyperaceae
Sedge family
Distributed worldwide
Cyperaceae morpholgy
Grass-like
Triangular, sharp and coarse stem → SiO2 crystals
Leaves covers with cuticle and have a W-shape
Tepals are reduced or absent → “spikelet” (not same as grasses)
Monosexual flowers, staminate and pistillate flowers can be arranged in the same or different spikelet
Flowers are covered with a glue
Female flowers surrounded with a bottle-sjaped bract → utricle
Importance of Cyperaceae
Species can be present in hay sample
Generally low digestibility and nutritive value
Consumption of the plants can damage the mouth
Planted in garden ponds
Uncertain identification below the genus low
Poaceae
Grass family
Spikelets with 1 or more florets
Toxins rarely occurs except cyanogenic glycosides
Endophytic fungi can produce toxins
Fructan accumulation of some species → laminitis
Practical importance of poaceae
Botanical hay analysis
The presence of “sour grasses” can decrease the quality of the hay
Low nutritive value, higher anti-nutritional effect
monocot
Flowering plants (angiosperms) whose seeds typically contain only one embryonic leaf, or cotyledon
Gymnosperm
seed-producing plants (spermatophytes)
any vascular plant that reproduces by means of an exposed seed, or ovule
