-Kumudinee, Subject Matter Expert at Edumarz.
Solution: Important characteristics of gymnosperms:
Gymnosperms are a group of organisms producing naked seeds (gymnos- naked and sperma- seeds) that is the seeds of these plants are not enclosed by fruit or any outer layer.
These plants can be of medium size or height, tall trees and shrubs.
The giant redwood tree Sequoia is one of the tallest trees in the world.
Tap root system is observed as well as the coralloid roots found in Cycas which are associated with nitrogen-fixing cyanobacteria.
Stem can be branched for example in Pinus and cedrus or it can be unbranched as in Cycas.
Leaves can be simple like in Pinus or compound as in pinnate of Cycas. These leaves are needle-like with thick cuticles and sunken stomata which help in prevention of water loss.
Gymnosperms produce two different types of spores, microspores and megaspores hence known as heterosporous.
Flowers are absent. Male and female cones have microsporophylls and megasporophylls arranged.
Pollination is carried out mainly by wind and pollen grains reach the pollen chamber of the ovule through the micropyle.
Male and female gametophytes are dependent on the sporophytes.
The seed contains haploid endosperm and remains uncovered.