Ecosystems - Extremophiles (GCSE Biology)

Extremophiles

Extremophiles

Adaptations of Extremophiles

Extremophiles are organisms that are adapted to live in extreme environments. This can include dangerous temperatures, pressures and salt levels. The majority of these organisms are not animals and plants, but bacteria.

• Some animals are extremophiles. Polar bears and penguins are well adapted to their respective Arctic and Antarctic conditions. Polar bears have strong senses of smell and sight in order to sense well camouflaged prey. Their white fur also provides a camouflage in order to hide and strike prey when they are least expected. More over, they are insulated by thick fur and blubber. They have a high surface area: volume ratio, which reduces heat loss as it reduces the speed of conduction.
• Penguins are adapted to the Antarctic conditions. Emperor penguins must survive in winds of around -60 degrees celsius. They must be adapted well for this. They have blubber and a thick, waterproof set of feathers for insulation. Moreover, they can insulate their eggs with their feet in the winter.
• Bacteria are found in deep sea volcanic vents. Ecosystems exist in the deep sea volcanic vents. Their areas have very high temperatures and pressures. Moreover, they are pitch black. Bacteria have adapted to live off the chemicals in these vents. They act as producers and provide food for tube-worms. These organisms have a symbiotic relationship. This means that they interact with one another and depend on each other to survive. Other organisms then feed on these bacteria and the worms. Organisms that can survive here are very highly adapted.

Plants in Extreme Conditions

Some plants are also adapted to live in extreme conditions.

Xerophytes

Xerophytes are plants adapted to survive in dry environments.

• Marram grass are xerophytes that are adapted to live on sand dunes. They have sunken stomata, hairs and rolled leaves which decrease the rate of transpiration by trapping a layer of humid hair by the surface of the leaves. They also have a thick, waxy layer on the epidermis to reduce evaporation and water loss.

Hydrophytes

Hydrophytes are plants adapted to survive in water.

• Water lilies are hydrophytes that are adapted to live in water. They have air spaces in their leaves to help them float on water so they can get the most exposure to sunlight. They also have stomata on the
  upper surfaces of the floating leaves to increase gas exchange. To protect them from currents, they have flexible stems.