What are gymnosperms?

What are gymnosperms?

The gymnosperms, also known as Acrogymnospermae, are a group of seed-producing plants that includes conifers, cycads, Ginkgo, and gnetophytes.

What happened to gymnosperms during the Carboniferous period?

The radiation of gymnosperms during the Carboniferous appears to have resulted from a whole genome duplication event around 319 million years ago. Early characteristics of seed plants are evident in fossil progymnosperms of the late Devonian period around 383 million years ago.

What is the most common gymnosperm in Florida?

Zamia integrifolia, a cycad native to Florida. Conifers are by far the most abundant extant group of gymnosperms with six to eight families, with a total of 65-70 genera and 600-630 species (696 accepted names). Conifers are woody plants and most are evergreens.

Are conifers gymnosperms or deciduous?

By far the largest group of living gymnosperms are the conifers (pines, cypresses, and relatives), followed by cycads, gnetophytes ( Gnetum, Ephedra and Welwitschia ), and Ginkgo biloba (a single living species). About 65% of gymnosperms are dioecious, but conifers are almost all monoecious.

Basically, Gymnosperms are the plants in which the ovules are not enclosed by the ovary wall, unlike the angiosperms. It remains exposed before and after fertilization, and before developing into a seed. The stem of a gymnosperm can be branched or unbranched.

When did gymnosperms first appear?

The fossil evidence suggested that they originated during the Paleozoic era, about 390 million years ago. Basically, gymnosperms are plants in which the ovules are not enclosed within the ovary wall, unlike the angiosperms. It remains exposed before and after fertilisation and before developing into a seed.

What is the haploid stage in gymnosperms?

The haploid stage is the dominant stage in the life cycle of the gymnosperms. In this stage, a multicellular haploid gametophyte develops from the spore and produces haploid gametes. The gametophyte when matures produces male and female gametes which join to form a diploid zygote.

Why do gymnosperms have sunken stomata?

The thick cuticle, needle-like leaves, and sunken stomata reduce the rate of water loss in these plants. The family of gymnosperms consist of conifers, the cycads, the gnetophytes and the species of Gynkgophyta division and Ginkgo biloba.