viernes, 20 de enero de 2012

The wonderful world of carnivorous plants I

When you hear "carnivorous plant" it's likely that you think in the Venus' Flytrap who "eats" every insect that perchs at it. But there are a lot of carnivorous plants very different and amazing, with complex mechanisms difficult to imagine, mechanisms that seem science fiction. In this entry and in the 2 next I'll explain all the generes of this wonderful type of plants. But before of that, I'll do a small introduction about the carnivorous plants.
The carnivorous plants live on the insects and small animals in order to get Nitrogen, because this element isn't present at the acid grounds where they live. These grounds are very hostile for the rest of the plants. But according to the rest of ways to get energy and other elements, they work like the others.
The most characteristic aspect of these plants are their traps, they are very varied and complex. Generally the basic action mechanism of the traps is:
1st.To attract by means of nectar
2nd. To fix by means of sticky substance
3rd. To digest by means of enzymes
They can "catch" from ants to little mice. These plants can live without eating any animal, but consecuently their growth will be slower.
The most of them live at very humid atmosphere with acid grounds, and they are from 1cm to 3m tall.
According to the cultivation, they are very difficult and delicated, generally the carnivorous plants need peat moss, with acid pH(5-6), distilled or rain water and a lot of humidity, although there are some exceptions. The typical causes of the carnivorous plants' dead are the lack of the demands and trying to force and manipulate the trap.
Some carnivorous plants due to their "monstrous" appearance have been used as ideas to create characters and creatures in movies, series, videogames... For some years...



And now, let's go with the generes:

Dionaea


This genere has only one species (Dionaea muscipula), "Dionaea" comes from "Diana"; the roman goddess of the hunting. This is the carnivorous plant "par excellence" because it's the most cultivated and known around the world, although it's originary of North and South Carolina (USA). It's also called Venus' Flytrap. According to its trap, at the end of the leaf it has 2 lobes with flexible thorns around its edges, at the centre there are 2 types of glands, one of them are nectar secretory glands and the other are secretory enzymes glands, and in the middle of the lobes there are detector tiny tentacles .
In the junction of the 2 lobes there are some glands that produce nectar, that substance attracts the insects, for example a fly. This small animal perchs on the lobes (in that moment they are open), and when the fly moves, it shaves the tiny tentacles, which activate the mechanism that closes the 2 lobes and traps the fly. The long flexible thorns around the edge prevents that the fly could scape. Then, the plant liberates the digestive enzymes that kill the fly.


Drosera

This is one of the generes with more species (around 170) distributed around the world, but principally in Australia. This plant has antitussive properties There are some groups: Subtropical, Pigmy, Nordic, Tuberous and Queensland. Generally the leaf ends with a lobe, where there are some short tentacles at the centre and long tentacles at the edge. The tentacles of the centre contains mucilage drops, this substance attracts the victims and fix them to the tentacles, and when the victim tries to escape, it produces some vibrations which the plant detects, and in that moment it's when the long tentacles moves and trap tre prey, and the enzymes are liberated by the plant.

Aldrovanda
This is a very odd plant; first because it's aquatic, and second because it has a very complex mechanism. There is only one species (Aldrovanda vesiculosa) distributed at Europe, Africa, Japan, India and Australia, in fresh water and acid pH(5-6) water areas. It has shooting naps that creates an air expulsion of its sack, causing the vacuum at the adjoining area and putting the victim to the interior and digesting it by means of enzymes. The small aquatic insects are attracted by its translucent leaves.


Heliamphora
This genere contains around 18 species, it's native of the Venezuelan steppes, it lives at flooded areas. This plant has another type of trap very different to the others. Its leaves have a structure that seems a sack or a tube open, empty and relatively big (15cm) with a "small bell" at the top that produces nectar. The prey goes to the small bell attracted by the smell, and when the it arrives it's very likely that it falls at the bottom of the tube, where instead of the digestive enzymes, there are bacteria and microorganisms which rots the prey and forms nutrients that the Heliamphora gets

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