Topic 6c: Vascular Plants: Flowering - Gymnosperms

Great Advances

1.  Reproduction is independent of water (think pollen!)
2.  Zygote (fertilized egg) develops in a protective feeding structure (seed) and can survive long unfavourable periods.

Gymnosperms (nyitvatermőek)
- seed not enclosed in fruit
- about 800 species
Classification:
There are many classes of gymnosperms.  3 are listed below.

1.  Cycads (cikászok)
-found in tropics and sub-tropics
-many resemble palm tress
-seed in cones
-male and female are separate plants

 Image from:  www.panzhihua-university.com

Image from: www.ilind.net

2.  Gingkos (páfrányfenyők)
- only 1 living species: Gingko biloba (all others died out about 65 million years ago)
-deciduous (loses its leaves)
-highly resistant to air pollution

Image from: www.mortonarb.org 

3.  Conifers (toboytermők, fenyőfélék)

- largest and most diverse class

- include: giant sequoia and redwoods (mammut fenyők), pines, firs, spruces (lucfenyő), larches (vörösfenyő), cedars (cédrus), junipers (boroka), yews (tiszafa)

 Scotch pine

 Red spruce

 Spruce

 Western Larch

 Yew

 Austrian Pine

- produce woody cones where the seeds are found
- needle or scale-like leaves
- vascular tissue:  xylem formed of tracheids, which are dead cells with lignified (elfásodott) cell walls, and xylem parenchyma, which are live cells that play a role in growth and repair
- most are evergreen (except larches)
- adapted to cold and dry climates:  needle-like leaves, thick waxy cuticle on leaves, sunken stomata (gázcserenyílások) and thick bark help to reduce water loss, evergreen allows for early photosynthesis, flexible needles and branches can handle heavy snowfalls without breaking


Life cycle of gymnosperms: