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Spore plants: examples, features, varieties

Botany lovers are skeptical when they listen to the legends of the night on Ivan Kupala. How can I find a fern flower? Who invented it, in general? How can you find something that never existed in nature?

Many nature lovers divide plants into flowering and non-flowering species. Non-flowering plants are called spore plants, examples of which will be considered today in the article.

Spore plants: first acquaintance

Let's start with a short description. The word "dispute" came to us from the Greek language. In translation, it means "seed" or "seed". This is a very small formation, the size of which is about 1 μm.

Spore plants have been formed for a very long time. In fact, they are direct descendants of the flora that has come from the ocean to land. Spore plants include not only the fern. Scientists subdivide them into two categories: higher and lower. In the first category - ferns, mosses, moss and horsetails. In the second - algae and lichens.

The life cycle of spore plants

If we talk about higher spore organisms, then they have a very interesting life cycle. Here you can see the alternation of asexual and sexual species. Accordingly, and reproduction, depending on the species, goes sexual or asexually. The full life cycle is continuous. The plant forms a gametophyte (organ of sexual reproduction) and sporophyte (an organ of asexual reproduction).

Evolution allowed these types of plants to develop in two directions. Two large groups were obtained: haploid and diploid. Describing spore plants, examples of the haploid group of which are mosses, scientists have proved that they have a more developed sexual gametophyte. The sporophyte in the haploid group has a subordinate status. Diploid direction of spore organisms (horsetail and ferns) has a highly developed sporophyte, and a gametophyte in the form of a sprouting.

The sex generation always has antheridia and archegonia. These are male and female organs. Male spermatozoa are mobile, the female sex cell is static. To fertilize it, the spermatozoon must get into the aquatic environment, through which it can reach the target. The fertilized egg forms the embryo from which the non-generational generation sprouts, that is, the sporophyte. The next stage of reproduction will occur in disputes that develop in sporangia.

Features

Not everyone knows how to distinguish spore plants. Examples of reasoning on this topic may look like this:

  1. Spore plants do not bloom. This species is biologically incapable of flowering.
  2. They have a unique life cycle. Sexual and asexual reproduction.
  3. Impossibility of sexual fertilization without the presence of water.

If the three characteristics are inherent in the plant in question, then this is a spore form.

Spore plants: ferns

It's hard to find someone who has never seen a fern. This ancient plant is used to decorate parks and garden plots. Room fern species are grown in flowerpots, and lovers of forest walks have many times seen lush and green fern thickets.

All ferns are dominated by pinnately dissected complex leaves. These spore plants (ferns) have the most notable sporangia. The location of these organs is the underside of the leaves.

For information, we add that ferns in nature are more than ten thousand. All this diversity is combined into 300 genera.

The structure of a spore plant on the example of mosses

Mosses can be attributed to the most primitive types of higher plants. All mosses are small in size representatives without conductive tissue. The subdivision into the stem and leaves of the moss is conditional. These amazing spore plants are examples of the ability to adapt to the conditions of nature.

So, the body of moss is conditionally divided into stem, leaves and roots. Yes, the roots of this plant are replaced by filiform outgrowths - rhizoids. Their main difference from real roots is the absence of a conductive tissue. In moss, each rhizoid is one or more living cells.

Mosses feel good in marshy places, in the shade or just in dampness. Mosses actively evaporate moisture, but fill the loss with the entire surface of the plant. Despite the fact that spore plants need water to breed, some moss species are able to wait for periods of drought, they even adapted to survive on rocky sites. How this happens is not completely understood.

The dominant generation of mosses is sexual. Sporophyte is completely dependent on gametophyte.

Spores can not form on the leaves, as in the fern, since the leaves themselves are very conventional. For these purposes, a spore box is arranged in the mosses, which rises above the sexual gametophyte on the leg-thread.

The feature of mosses is the possibility of vegetative reproduction. In this process, kidneys and nodules are involved. If the vegetative part is separated from the main plant, then it develops into an independent individual.

A bit about the lower forms

We will not list all the lower spore plants. Examples that are interesting to describe are algae. These plants are not as numerous as ferns and lichens, they are slightly more than a hundred species. The habitat of this flora is water. Algae do not have leaves and roots. They are attached to the ground or stones with transparent hooks. Algae is subdivided into 11 divisions, 4 of which the person has learned to use for his own purposes.

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