Characteristics aves

Characteristics aves

    Both morphologically and biologically, they are highly adapted for flight although many species have lost the powers of flight.

 

    They have scaly legs and feathers (which are specialized scales). Their bones are light (an adaption for flight), and are honeycombed in most species. The fore-limbs are highly modified that, along with their associated feathers, in most species are adapted for flight.

 

    Further adaptations for flight include the urinary system that excretes nitrogenous waste as uric acid crystals, massive reduction in size of reproductive organs when not breeding, the development of only one ovary or testis when breeding, and a massive sternum to anchor flight muscles.

 

    All species lay eggs

 

    They are toothless animals, but have a beak

 

    As certain times of year some species lay-down a fat layer for insulation and/or a food reserve that can be utilized in long migratory flights

 

    They have a highly efficient cardiopulmonary system, with an endothermic heart (they are warm-blooded).

 

 

The difference :

Monocotyl:

have a single beans and root fibers

dicotyl:

has two beans and roots-riding

 

the role of fungi:                            

    Recycling

    Fungi, together with bacteria, are responsible for most of the recycling which returns dead material to the soil in a form in which it can be reused. Without fungi, these recycling activities would be seriously reduced. We would effectively be lost under piles many metres thick, of dead plant and animal remains.

 

    Mockeries and plant growth

    Fungi are vitally important for the good growth of most plants, including crops, through the development of myocardial associations. As plants are at the base of most food chains, if their growth was limited, all animal life, including human, would be seriously reduced through starvation.

 

    Food

    Fungi are also important directly as food for humans. Many mushrooms are edible and different species are cultivated for sale worldwide. While this is a very small proportion of the actual food that we eat, fungi are also widely used in the production of many foods and drinks. These include cheeses, beer and wine, bread, some cakes, and some soy bean products.

 

    While a great many wild fungi are edible, it can be difficult to correctly identify them. Some mushrooms are deadly if they are eaten. Fungi with names such as 'Destroying Angel' and 'Death Cap' give us some indication that it would not be a terribly good idea to eat them! In some countries, collecting wild mushrooms to eat is a popular activity. It is always wise to be totally sure that what you have collected is edible and not a poisonous look-a-like.

  

    Medicines

    Penicillin, perhaps the most famous of all antibiotic drugs, is derived from a common fungus called Pencillium. Many other fungi also produce antibiotic substances, which are now widely used to control diseases in human and animal populations. The discovery of antibiotics revolutionized health care worldwide.

 

    Some fungi which parasite caterpillars have also been traditionally used as medicines. The Chinese have used a particular caterpillar fungus as a tonic for hundreds of years. Certain chemical compounds isolated from the fungus may prove to be useful treatments for certain types of cancer.

 

    A fungus which parasite Rye crops causes a disease known as Ergot. The fungus can occur on a variety of grasses. It produces small hard structures, known as sclert. These sclerotia can cause poisoning in humans and animals which have eaten infected material. However, these same sclerotic are also the source of a powerful and important drug which has uses in childbirth.

    Fungi such as the Chinese caterpillar fungus, which parasite insects, can be extremely useful for controlling insect pests of crops. The spores of the fungi are sprayed on the crop pests. Fungi have been used to control Colorado potato beetles, which can devastate potato crops. Spittlebugs, leaf hoppers and citrus rust mites are some of the other insect pests which have been controlled using fungi. This method is generally cheaper and less damaging to the environment than using chemical pesticides.

 

    Crop Diseases

    Fungal parasites may be useful in bio control, but they can also have enormous negative consequences for crop production. Some fungi are parasites of plants. Most of our common crop plants are susceptible to fungal attack of one kind or another. Spore production and dispersal is enormously efficient in fungi and plants of the same species crowded together in fields are ripe for attack. Fungal diseases can on occasion result in the loss of entire crops if they are not treated with antifungal agents.

 

    Animal Disease

    Fungi can also parasite domestic animals causing diseases, but this is not usually a major economic problem. A wide range of fungi also live on and in humans, but most coexist harmlessly. Athletes foot and Candida infections are examples of human fungal infections.

 

    Food Spoilage

    It has already been noted that fungi play a major role in recycling organic material. The fungi which make our bread and jam go moldy are only recycling organic matter, even though in this case, we would prefer that it didn't happen! Fungal damage can be responsible for large losses of stored food, particularly food which contains any moisture. Dry grains can usually be stored successfully, but the minute they become damp, molds are likely to render them inedible. This is obviously a problem where large quantities of food are being produced seasonally and then require storage until they are needed.