Gymnosperms and angiosperms Flashcards
conifer species numbers
550 species
Gymnosperm members
Conifers ginkgophytes, gnetophytes
Conifer forms
Trees and shrubs
Conifer general characteristics
○ Stress tolerators
○ Survive drought or cold
○ Provide most of worlds lumber
○ Susceptible to bark beetles when stressed
○ From wet to dry and warm to cold
Conifer leaves
○ Simple needles or scales
○ perennial
Most conifers are Evergreens
conifer wood
○ Consists of tracheids
○ Parenchyma cells in rays
○ Resin ducts
○ Sieve cells in phloem but no sieve tubes
conifer embolism
○ Narrow tracheids cause thawing sap to collapse instead of expand
○ Makes them more conditioned for cold temperatures
○ Allow tracheids to maintain water transport over extended period
Conifer transpiration adaptations
○ Thick cuticle and sunken stomata
- Wax tubules close stomatas as well (stomatal plugs)
These lower transpiration of conifers
Pine Family
conifers
Largest pine family
Firs, spruces, larches
Thrive in mountain forest
Dominant in boreal forest
North hemisphere
Cypress Family
conifers
Junipers, redwoods, cypress
Bald cypress –> swamp sourth east us
Araucaria Family
conifers
Wollemi pine
- Only known through fossils
□ Small pop found in Australia
- Ginkgophytes
gymnosperm
- Ginko biloba–> one species
○ Urban parks and along streets
○ Wood like conifers
○ Male & female
○ Genus been around 150 million years
○ Deciduous
○ Leaves split like a ballsack
- Gnetophytes
○ Have vessels
○ Welwitschia 2 leaves
§ Grows in africa deserts
§ Some are 1000 yrs old
○ Ephedra
§ American southwest
CAM photosynthesis
angiosperm how many species and when did first appear
250k species
First appeared 130 mya
angiosperm forms
○ Lianas, herbs, shrubs, trees
