For all varieties of plants to survive they need to have adaptations that allow them to survive in their environment. There are many factors that cause plants to develop adaptations. For some of these adaptations it is known that plants can sometimes change the way they photosynthesise, respire and transpire which can give them extra protection from various factors.
Lichens are capable of surviving in a wide range of environmental conditions and they have the ability to grow on any surface. Lichens are always usually found growing on bark, leaves, moss and also on other lichens. They can also grow on rock, walls, gravestones, roofs, exposed soil surfaces and in the soil
Lichens are composed of both a fungus and photosynthetic algae. This allows them to have a symbiotic relationship that is of equal benefit to both of them. This relationship allows them to survive in hostile environments that would be otherwise challenging for them both if they didn’t have this type of relationship. Fungus makes up 80% of the lichen and the remaining 20% is made up of algal symbionts. Lichens produce carbohydrates which is an end product in photosynthesis. This end product provides nutrition for lichens as they are capable of digesting carbohydrates. The fungus part of the Lichen has thick cell walls meaning they are able to store both water and food which are essential nutrients for the Lichen (2013.extrememarine.org.uk, 2015).
When there is any moisture available it is taken in by the fungus and undergoes a mechanical change. This change allows more light in therefor triggering algal photosynthesis. This will then provide both new food and tissue for the Lichen. However if the atmosphere is dry then the Lichen will remain dormant and not grow as it will be conserving its energy.
Venus flytrap (Dionaea muscipula)
Venus flytraps are carnivorous plants that are native to the wetlands in the North and South of Carolina in the United States. However, they are also popular as houseplants. When the flytrap is triggered it quickly snaps shut and imprisons its prey. This process can be triggered by a time and touch sensitive mechanism (Bbc.co.uk, 2015). As soon as the prey has been digested the Venus flytrap opens once again to trap another prey. Each trap on the Venus flytrap can only function three or four times, after this it photosynthesizes like a normal leaf or dies back. This particular plant thrives in an environment that has plenty of sunlight, good air circulation, high humidity and soil that is acidic and contains poor amounts of nutrients (Theflytrapisu.blogspot.co.uk, 2013).
Venus flytraps have adapted themselves to their usual wetland environment by becoming carnivores, therefore they digest all of the prey they catch. This is due to the soil in their natural habitat containing poor amounts of nutrients (nitrogen) which means they would not be able to fully support themselves off of their natural habitat.
Another adaption they have made is their ability to trap prey. This is carried out by the two leaf parts that have tiny sensitive hairs. These hairs have the ability to sense the presence of any prey that gets close to their trap. When the prey is sensed, the trap quickly closes trapping the prey. Afterwards the leaf secretes a mixture of digestive enzymes that will help to break down the prey. These enzymes will help make it easier for the plant to digest their prey. Without this the Venus flytrap would struggle to survive in the poor soil of its natural environment.
The leaves of this plant have a bendable midrib helping them to close. To help identify the prey, the edges of the leaves are lined with tooth like hairs. These hairs are very sensitive to the vibrations of insects, therefore this will notify the plant when prey are nearby.
To help lure the insects towards the Venus flytrap, the plant has a strong sweet smell of nectar. Once the prey become trapped inside, the digestive glands on the insides of the leaves release enzymes that will dissolve the prey. The hairs on the leaves lace together like fingers helping to trap the prey and allowing the enzymes to break down the prey making it more digestible.
The leaves of the Venus flytrap have the ability to photosynthesise like a normal plant and transpires by evaporation through the stomata on the leaves. The stomata also exchange carbon dioxide and oxygen.
Bell heather (Erica cinerea)
Bell heather can be found on dry moorlands and it has the ability to grow to about 60 centimetres. The small leaves are dark green and the flowers are reddish-purple that are found in groups of 2.
Heather plants have a symbiotic relationship with fungi. The fungi grows inside and between some of the heather’s root cells. The Heather benefits when there is fungi and similarly the fungi benefits from some of the plants nutrients meaning they have a symbiotic relationship. To help disperse its seeds the Bell Heather has rich nectar and pollen, helping to attract insects such as bees (Virtualheb.co.uk, 2015).
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