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Pteridophytes



Fern: most common example of pteridophyte

What are

Pteridophytes are vascular plants that do not have seeds.

Main features

- Cormum composed of root, stem and leaves;

- They are tracheophytes, that is, they have a conduction system that transports the sap from the roots to the leaves. In these ducts are also transported food to the rest of the body;

- Have leaves divided into leaflets;

- New leaves appear rolled up;

- Most species have sexual reproduction, but some can reproduce asexually through budding.

- The sap transport system enables the plant to be supported;

- Possess the ability to thrive on tree trunks;

They have a stem, called a rhizome, much like a root.

Examples:

- Avencas

- Ferns

- Raxins

- Horsetail

Pteridophytes Reproduction

1 - In sporangia (spore producing organs) of plants, through meiosis, diploid cells are transformed into haploid.

2 - The sporangia breaks and the haploid spores fall to the ground.

3 - The spores germinate giving rise to the protalo (heart-shaped structure).

4 - Protalo has the ability to produce gametes, as it is a sexed plant. This phase lasts a short time.

5 - The protalo has a female and a male reproductive organ.

6 - Anterozoids (male gametes) go to the oosphere (female gamete of plants) fertilizing it.

7 - The born embryo is a diploid. The new adult plant is created because the embryo's cells divide by mitosis.

Curiosities

- Pteridophytes were the first to develop a system for the transport of sap.

- They are widely used as ornamental plants, especially ferns.

- Some species of ferns can grow up to 15 meters.