GENERAL CHARACTERS
- Gymnosperm is the group of Tall trees, the tallest being Sequoia reaching upto 120m in height.
- Gymnosperms are the first seed forming plant group i.e. First Spermatophytes.
HABIT
- Gymnosperms mostly produces tall or medium size trees while a few species are found as woody shrubs.
HABITAT
- Mostly found in temperate areas having high altitudes, some are found in tropical or sub-tropical regions.
LIFE CYCLE
- Shows Diplontic life cycle
BODY STRUCTURE
- The main body is the diploid Sporophyte which is well differentiated into roots, stem and leaves.
- STEM
- Woody i.e. Secondary growth is present
- Branched – Pinus, Cedrus
- Unbranched – Cycas
- ROOTS
- Tap roots.
- Pinus – Symbiotic (Mycorrhizal) association with Fungi
- Cycas – Coralloid roots – Symbiotic association with BGA (Anabaena cycadae)
- LEAVES
- Either Simple (Pinus) or Palmately compound (Cycas)
- Leaves are modified to withstand extreme conditions as
- Thin, needle like to reduce surface area
REPRODUCTION
- Asexual reproduction and Vegetative propagation are absent in Gymnosperms.
- Sexual reproduction occurs by formation of gametes and spores.