Sunday, January 4, 2009
ECOLOGY homework
???HOW DO THE PHYSICAL FEATURES OF THE SURROUNDINGS AFFECT ORGANISMS?WHAT ARE THESE PHYSICAL FACTORS?GIVE EXAMPLES OF HOW ORGANISMS ADAPT TO THESE PHYSICAL FACTORS.???
Physical features that make up the abiotic environment include:
- Light intensity(determined by climate)
2. Temperature(determined by climate)
3.
Amount of water available(determined by climate)4.
Oxygen content
5.
Salinity(salt concentration)of soil/water
6.
pH of soil/water
These physical features of the surroundings affect the organisms as the organisms rely directly or indirectly on plants for food. Physical features of the surroundings and the nature of the soil determine the types of plants found in a region, thus, the animals that live in a region are determined by the plants growing in that region. The animals will live where their source of food is and have adaptations to the environmentExamples of how organisms adapt to these factors are:
- Light intensity: Bats are specially adapted to move about in the dark by bouncing sound waves off objects around them.
- Temperature: Animals that live in polar regions where temperatures are constantly freezing have a layer of fats or a coat of fur to ensure that they are kept warm.
- Amount of water available: Cacti are zerophytes They have fleshy stems so that they could store water.
- Oxygen content: Fish living in water of low oxygen content are usually air-breathers. They can come to the surface of the water to gulp for air
- Salinity of soil/water: Saltwater/marine fishes have a waterproof coat consisting of closely-fitting scales covered by a slimy mucous material. This reduces the rate of water loss which affect the animal's exchange of gases.
- pH of soil/water: Drastic/sudden changes in pH of the water which an aquatic organism live in may die. Thus, the freshwater bony fish adapt by taking in salts in the gills by cells(to cope with the salt loss problem)and has a kidney that reabsorbs salts and produces large amounts of dilute urine.(to cope with the excess water entering body cells)
???ARE ORGANISMS INTERDEPENDENT?WHY????
Organisms are interdependent. A change in one population affects the other populations of the comunity. Example, if the population of worms living in field in a farm decreases, the population of chickens would probably derease too as there is less food for them. Therefore, the chickens may start feeding on other popuations of insects. This would affect the ecosystem. It is like a web, breaking a single strand would affect the whole system.
being interdependent...Labels: pictures from www.flickr.com
