Question

Are all trees gymnosperms?

Answer 1

Hint: Plants are mainly divided into two subkingdoms cryptogams and phanerogams. The cryptogams consist of non-flowering plants which are generally small in size whereas phanerogams are flowering size with all sizes from shrubs to tall trees.

Complete answer:
No, all trees are not gymnosperms. Trees come under both gymnosperm and angiosperm inside the subkingdom phanerogamae. Gymnosperm only consists of those trees which have conifers with the presence of cones and strobili. It does not have trees with seed enclosed inside the fruit.
The plant kingdom is divided into mainly non-flowering cryptogam and flower producing phanerogam which is further divided into thallophyta, Bryophyta, Pteridophyta, gymnosperm and angiosperm.
The gymnosperm can be classified based on its vascular system, naked seeds, conifers and deciduous trees. The gymnosperms are perennial, with woody trees and bushy shrubs. It generally shows the taproot system and leaves are devoid of lateral veins and the function of lateral leaves are performed by transfusion tissue. They produce two types of spores therefore they are heterosporous. Pollination takes place mostly by wind and pollen grain reaches the pollen chamber by micropyle. The endosperm represents the female gametophyte and it is food containing tissue which produces under seed led to the development of an embryo.

Note:
Some gymnosperm has a mycorrhizal association in their root whereas the plant with coralloid roots has nitrogen-fixing cyanobacteria. The vascular bundle of both gymnosperm and angiosperm is similar but the xylem of gymnosperm does not consist of vessels and phloem does not consist of companion cells.