Gymnosperms
The division Spermatophyta includes all seed-bearing plants. It has been branched into two subdivisions- Gymnosperms and Angiosperms. Gymnosperms are the most primitive group of seed plants, flourished in the Devonian period of the Palaeozoic era. The geological records show that they were ascendant plants over the earth’s surface during the Jurassic and Cretaceous periods of the Mesozoic era. There are about 70 genera and 725 species of living gymnosperms, spread across the temperate and tropical regions of the world. They even occur in arctic zones.
Gymnosperms are woody plants that do not bear flowers. Seeds are exposed or naked—better adaptation for land habit. Fertilization is siphonogamous. Seeds are born on structures called cones. Due to the development of cambium, they show secondary growth. The members of numerous early groups of Gymnosperms (e.g.. Cycadofilicales, Bennettitales, Cordaitales) are extinct today and only their preserved remains (fossils) are known. Other groups like Cycadales, Ginkgoales, Coniferales, and Gnetales are represented by both living and fossil members.
They are marked by the presence of naked ovules, unlike angiosperms, seeds of gymnosperms are not enclosed in ovaries. Gymnosperms are infrequently called ‘Phanerogams without ovary’.
Difference between Angiosperms and Gymnosperms
All the species of plants come under the category of the plant kingdom. They consist of eukaryotic, multicellular, and autotrophic organisms. Autotrophs are those organisms that make their own food with the help of sunlight, water, soil, minerals, etc. Plants contain chloroplast and chlorophyll pigment, which is needed for photosynthesis. The process of making their own food is known as photosynthesis. Plants have distinct varieties with different characters. They can’t displace. The plant kingdom plays a great role in society by providing information regarding its importance.
R.H Whittaker gives 5 kingdom systems which he stated are kingdoms like Monera, Protista, Fungi, Animalia, and Plantae. Kingdom Plantae has mainly 5 groups, i.e., Algae, Bryophytes, Pteridophytes, Gymnosperms, and Angiosperms. Let us have a glance over the difference between gymnosperms and angiosperms.