which is a gymnosperm

What are examples of gymnosperm plants?

Gymnosperms are seed-bearing vascular plants, such as cycads, ginkgo, yews and conifers, in which the ovules or seeds are not enclosed in an ovary. The word "gymnosperm" comes from the Greek word gymnospermos, meaning "naked seeds".

What are gymnosperm plants?

gymnosperm, any vascular plant that reproduces by means of an exposed seed, or ovule—unlike angiosperms, or flowering plants, whose seeds are enclosed by mature ovaries, or fruits. The seeds of many gymnosperms (literally, “naked seeds”) are borne in cones and are not visible until maturity.

What are gymnosperms answer?

Gymnosperm is a seed-producing plant that includes conifers, cycads, gnetophytes and ginkgos. They do not produce flowers or fruits and have naked seeds.

What is the most common gymnosperm?

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.

What are the 4 groups of gymnosperms?

Four major groups within the gymnosperms are usually recognized - these sometimes each considered its own phylum (Cycadophyta, Ginkgophyta, Gnetophyta, Pinophyta). Here we will consider the gymnosperms to be a natural group and recognize the group as all Pinophyta.

Is Onion a gymnosperm?

No, onion is an angiosperm. It is a monocot.

Is Pine Tree a gymnosperm?

Conifers like the spruce, cedar and pine tree are gymnosperms and have seeds on cones. Most coniferous trees are evergreen and are specially adapted to survive in areas with lots of snow.

Is Pinus a gymnosperm?

Pinus is a gymnosperm because it.

Is a fern a gymnosperm?

Ferns are distinguishable from angiosperms by their lack of flowers, and from angiosperms and gymnosperms (such as conifers) by their lack of seeds. Instead, ferns, like all other so-called “lower plants”, colonise new sites by the dispersal of unicellular spores produced in sporangia.

What are 3 examples of angiosperms?

Angiosperm Examples Grains including rice, corn, and wheat are also examples of Angiosperm. In these plants, the pollination process is carried out by the wind. Other examples of Angiosperms include roses, lilies, Broccoli, kale, Petunias, Eggplant, Tomato, Peppers and sugarcanes.

Is coconut A gymnosperm?

No, coconuts are angiosperms. They belong to the family Arecaceae.

Which of the following is NOT a gymnosperm?

Fern does not belong to the Gymnosperm. The Gymnosperms are the plants in which the ovules remain exposed before and after fertilization and are not enclosed by ovary wall. Cycas, Pinus and Ginkgo are the examples of Gymnosperm. Fern is an example of Pteridophytes.

What is difference between gymnosperms and angiosperms?

The key difference between angiosperms and gymnosperms is how their seeds are developed. The seeds of angiosperms develop in the ovaries of flowers and are surrounded by a protective fruit. Gymnosperm seeds are usually formed in unisexual cones, known as strobili, and the plants lack fruits and flowers.

Are trees gymnosperms?

Gymnosperms are woody plants, either shrubs, trees, or, rarely, vines (some gnetophytes). They differ from flowering plants in that the seeds are not enclosed in an ovary but are exposed within any of a variety of structures, the most familiar being cones.

Is gymnosperm a flowering plant?

Whereas gymnosperms have no flowers or fruits and have naked seeds on the surface of their leaves. Gymnosperm seeds are configured as the cones.

What is a difference between ferns and gymnosperms?

Ferns are flowerless plants that do not have any seeds whereas gymnosperms do have seeds of their own.

What is gymnosperm?

Gymnosperm is a seed-producing plant that includes conifers, cycads, gnetophytes and ginkgos. They do not produce flowers or fruits and have naked...

Do gymnosperms have an embryo?

Yes, gymnosperms do have an embryo. In gymnosperms, the ovule becomes the seed encasing the embryo and endosperm in a seed coat, but it does not de...

Give a few examples of gymnosperms.

Cycas, pinus, Thuja, Cedrus, Abies, Larix are some of the examples of gymnosperms.

How are gymnosperms different from an angiosperm?

Angiosperms are called flowering plants, whereas gymnosperms are called non-flowering plants. Angiosperms have seeds enclosed in an ovary (a fruit)...

How are the gymnosperms classified?

The gymnosperms are classified as- Cycadophyta, Ginkophyta, Gnetophyta, Coniferophyta.

Which stage dominates the life cycle of 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...

Where are gymnosperms found?

Gymnosperms are usually found in colder regions when snowfall occurs. However, cycads are found in dry and tropical regions.

What are gymnosperms?

Various gymnosperms. The gymnosperms, also known as Acrogymnospermae, are a group of seed-producing plants that includes conifers, cycads, Ginkgo, and gnetophytes. The term gymnosperm comes from the composite word in Greek: γυμνόσπερμος ( γυμνός, gymnos, 'naked' and σπέρμα, sperma, 'seed'), literally meaning 'naked seeds'.

Which phyla are gymnosperms in?

Organisms that belong to the Cycadophyta, Ginkgophyta, Gnetophyta, and Pinophyta (also known as Coniferophyta) phyla are still in existence while those in the Pteridospermales and Cordaitales phyla are now extinct. By far the largest group of living gymnosperms are the conifers (pines, cypresses, and relatives), followed by cycads, ...

What are the two types of spores?

Two spore types, microspores (male) and megaspores (female), are typically produced in pollen cones or ovulate cones, respectively. Gametophytes, as with all heterosporous plants, develop within the spore wall. Pollen grains (microgametophytes) mature from microspores, and ultimately produce sperm cells. Megagametophytes develop from megaspores and ...

What is the name of the tree that has a fern-like morphology?

The fossil record of gymnosperms includes many distinctive taxa that do not belong to the four modern groups, including seed-bearing trees that have a somewhat fern -like vegetative morphology (the so-called "seed ferns" or pteridosperms ).

How do megagametophytes develop?

Megagametophytes develop from megaspores and are retained within the ovule . Gymnosperms produce multiple archegonia, which produce the female gamete. During pollination, pollen grains are physically transferred between plants from the pollen cone to the ovule. Pollen is usually moved by wind or insects.

What is the largest group of gymnosperms?

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. Some genera have mycorrhiza, fungal associations ...

What is the non-encased condition of seeds?

The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants ( angiosperms ), which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or solitary as in yew, Torreya, Ginkgo.

What is a gymnosperm?

Gymnosperms are a group of plants which produce seeds that are not contained within an ovary or fruit. The seeds are open to the air and are directly fertilized by pollination. “Gymnosperm”, from the Greek, gymnos, “naked” and sperma, “seed”, develop their seeds on the surface of scales and leaves, which often grow to form cone or stalk shapes, ...

What is the most numerous gymnosperm?

Conifers, in the division Pinophyta or Coniferophyta, are the most numerous of the gymnosperms; woody and with vascular tissue, these are cone bearing trees and shrubs.

What is the life cycle of a gymnosperm?

Gymnosperm Life Cycle. Gymnosperms reproduce with an alteration of generations, meaning their reproductive cycle has both haploid and diploid phases. As in all other vascular plants, gymnosperms have a sporophyte dominant life cycle (the sporophyte is the diploid multicellular stage, which comprises the body of the plant, i.e., a leafy tree).

Why are gnetophyta distinguishable?

The gnetophyta are distinguishable within the gymnosperms because they have vessel elements, a system of channels mostly found in the angiosperms, which transport water within the plant.

What is the name of the tree with a single, stout, cylindrical, woody trunk?

The appearance of the cycads (division Cycadophyta) typically constitutes a single, stout, cylindrical, woody trunk and a crown of large, hard and stiff, evergreen compound leaves, which grow directly from the trunk in a rosette formation. The cycads are dioecious, meaning that each individual plant is either all male or all female.

What is the male cone?

The male cone, called the microsporophyll, is a small, spongy, leaf-like organ which bears the microsporangium. The microsporangium contains the male microspores, which undergo meiosis to generate the male gametophyte, pollen. The pollen grain contains the pollen tube cell and the generative cell (which contains two sperm, although one dies).

What is the phase of a gametophyte?

The gametophyte phase is relatively short, and sees gametes produced on the reproductive organs , which are usually cones. The female ovulate cone, or megasporophyll, bear the megasporangium, diploid cells, which undergo meiosis to produce four haploid spores. Of these haploid spores, only one survives as the megaspore.

What is a gymnosperm?

Robert Brown. ... (Show more) Full Article. gymnosperm, any vascular plant that reproduces by means of an exposed seed, or ovule —unlike angiosperms, or flowering plants, whose seeds are enclosed by mature ovaries, or fruits. The seeds of many gymnosperms (literally “naked seeds”) are borne in cones and are not visible until maturity.

What is the visible part of a gymnosperm?

In all living gymnosperm groups, the visible part of the plant body (i.e., the growing stem and branches) represents the sporophyte, or asexual, generation, rather than the gametophyte, or sexual, generation. Typically, a sporophyte has a stem with roots and leaves and bears the reproductive structures. As vascular plants, gymnosperms contain two conducting tissues, the xylem and phloem. The xylem conducts water and minerals from the roots to the rest of the plant and also provides structural support. The phloem distributes the sugars, amino acids, and organic nutrients manufactured in the leaves to the nonphotosynthetic tissues of the plant.

How do gymnosperms fertilize?

In many gymnosperms, a sticky “pollination droplet” oozes from a tiny hole in the female megasporangium to catch pollen grains. The droplet is then resorbed into the megasporangium for fertilization . In other species, the pollen grain settles on the surface of the megasporangium, where the male gametophyte develops further. A pollen tube emerges from the grain and grows through the megasporangium toward the multicellular egg-containing structure called the archegonium. The egg and sperm continue to mature, the nucleus of the latter undergoing additional divisions resulting in two male gametes, or sperm. Interestingly, cycads and Ginkgo are the only seed plants with flagellated sperm. By the time the pollen tube reaches the archegonium, both the egg and sperm are fully mature, and the egg is ready to be fertilized.

How long does it take for a sporophyte to mature?

The time interval between pollination and maturation of the embryo into a new sporophyte generation varies among different groups, ranging from a few months to over one year (in pine, for example). In gymnosperms such as cycads and Ginkgo, the seed coat is known as the sarcotesta and consists of two layers.

How many cotyledons does a gymnosperm have?

At maturity, a gymnosperm embryo has two or more seed leaves, known as cotyledons. Cycads, Ginkgo, and gnetophytes have two cotyledons in the embryo; pine and other conifers may have several (eight is common; some have as many as 18).

What is the gametophyte phase?

The gametophyte phase begins when the microspore, while still within the microsporangium, begins to germinate to form the male gametophyte. A single microspore nucleus divides by mitosis to produce a few cells. At this stage the male gametophyte (called a pollen grain) is shed and transported by wind or insects.

What is the female ovulate cone?

Female ovulate cones, called megastrobili, may be borne on the same plant that bears microstrobili (as in conifers) or on separate plants (as in cycads and Ginkgo ). A megastrobilus contains many scales, called megasporophylls, that contain megasporangia.

What are Gymnosperms?

The word “Gymnosperm” comes from the Greek words “gymnos” (naked) and “sperma” (seed), hence known as “Naked seeds.” Gymnosperms are the seed-producing plants, but unlike angiosperms, they produce seeds without fruits. These plants develop on the surface of scales or leaves, or at the end of stalks forming a cone-like structure.

What are the characteristics of gymnosperms?

Following are the important characteristics of gymnosperms: They do not produce flowers. Seeds are not formed inside a fruit. They are naked. They are found in colder regions where snowfall occurs. They develop needle-like leaves. They are perennial or woody, forming trees or bushes.

How resilient are ginkgo trees?

Ginkgo trees are also very resistant to pollution, and they are resilient against diseases and insect infestations. In fact, they are so resilient that after the nuclear bombs fell on Hiroshima, six Ginkgo trees were the only living things to survive within a kilometre or two of the blast radius.

How are stigmas pollinated?

Since stigma is absent, they are pollinated directly by the wind.

When did gymnosperms first appear?

The fossil evidence suggested that they originated during the Paleozoic era, about 390 million years ago .

Can gymnosperms be branched?

It remains exposed before and after fertilisation and before developing into a seed. The stem of gymnosperms can be branched or unbranched. The thick cuticle, needle-like leaves, and sunken stomata reduce the rate of water loss in these plants.

Is a gymnosperm a plant?

Gymnosperms are non-flowering plants belonging to the sub-kingdom Embophyta. The seeds are not enclosed in an ovary or fruit. They are exposed on the surface of the leaf-like structures of the gymnosperms. They can be classified as Coniferophyta, Cycadophyta, Ginkgophyta and Gnetophyta.

What is a gymnosperm?

Gymnosperms which is also referred to as Acro gymnospermae are a group of flowerless plants that produce seeds and cones. The term gymnosperm literally translates to "naked seed" as they are flowerless. This is due to the fact that gymnosperm seeds are not encapsulated within the ovaries. Instead, they are exposed on the surface ...

Where are gymnosperms found?

A lot of species which are from the Ephedra are shrubs that are mostly found in desert areas of the American highlands or the cool areas of Himalayan Mountains in India.

How many species of gymnosperms are there?

Gymnosperms are a small cluster of seed plants which are represented by only 900 living species.

What are the only surviving plants in Gymnosperm?

The only surviving plants of the ginkgophyte division of gymnosperm are the ginkgo biloba. These plants are very much exclusive to China in a naturally growing environment. Ginkgoes can live for an extremely long time at an estimation of thousands of years. These are characterized by their fan-shaped leaves which commonly change their colors in the season of autumn. Ginkgo biloba is also very large and with the tallest trees ranging to about 160 feet. The older the tree, the thicker the trunks and the deeper are the roots. These thrive very well in sunlit areas around the world and where they can receive plenty of water and have access to lots of soil drainage. Just like the cycads, these ginkgo plants can either consist of male or female cones. The sperm cells use a hair like a feature called flagella allowing it to swim towards the egg in the ovule. These trees are very durable and also surprisingly fire resistant. On top of that, they are resistant to pests and diseases.

Which cell contains ovules and a megasporangium?

Female Cones - The megasporophylls form a group and are known as the female Strobilus or cones. They contain the ovules having the megasporangium. Hence, produces the haploid megaspores and a megaspore mother cell.

What are some examples of gymnosperms?

There are other recognizable examples of these trees and shrubs which include spruces, pines, ginkgoes, and firs. These classes of gymnosperms are readily available in biomes such as ...

What is the name of the group of conifers?

Coniferophyta. The Coniferophyta sub-group as its name suggests consists of conifers, which contain pines, cypresses, and other close relatives. Coniferophy ta encompasses an enormous variety of species in the gymnosperms.

What is a gymnosperm?

Gymnosperms are a large group of plants that do not make flowers at all and have a unique form of reproduction. This is a very old group of plants, first showing up over three hundred million years ago. The word Gymnosperm means naked seed. Most flowering plants have their seeds inside of fruits.

What are some examples of non-flowering but also non-Gymnosperm plants?

Asplenium nidus 'plicatum' or plicated Bird's Nest Fern (left) and Cyathea aramaganensis (a tree fern- right)- two examples of non-flowering but also non-Gymnosperm plants. Some generalizations: Gymnosperms do not make flowers or fruits. Most gymnosperms are trees or large shrubs.

What are some examples of monocots?

Examples of a monocot (left) and dicot (right) Angiosperms, or flowering plants. Cedrus atlantica with female cones (photo mgarr)- left; Macrozamia pauli-guilliami female cycad cones (right)- two Gymnosperms showing reproductive structures- no flowers on these two kinds of plants. Gymnosperms are a large group of plants ...

What is the name of the plant with leathery leaves?

Encephalartos horridus (left)- photo Xenomorf and Encephalartos ferox (right) showing some of the many variations in cycad leaves- all are very leathery-plastic-like

Is a gymnosperm monoecious?

Many gymnosperms are dioecious (separate male and female plants), but I could not say that most are, as so many conifers are monoecious (male and female cones on the same tree).

Is a pine tree a gymnosperm?

And indeed, pines are gymnosperms. But it turns out there are lots of trees that look to me like pine trees that are belong to a dozen or more other families of gymnosperm. And it also turns out there are many plants out there that are gymnosperms that are not conifers at all. Some of these are now among my favorite plants (namely the Cycads).

Is there fruit in Gymnosperm?

But there no fruits in the Gymnosperm world and the seeds are ‘naked' within cone-like structures. There is a coating surrounding each seed in some cases (like in the cycads) and this coating is sometimes referred to as the fruit, but I think that is an incorrect usage of the word fruit.

Overview

Classification

Diversity and origin

Uses

Life cycle

Genetics

General bibliography

External links