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I. Most sarcodines are free living; others are parasitic. One of these parasites is the causative organism of amebic dysentery
cilliophora-Many
are also of considerable importance as they are responsible for various diseases and infections.
Some zoomastigina
cause important human diseases. Trypanosomes cause sleeping sickness and Chagas disease while the well known water borne disease
giardiasis is cause by an organism in the genus Giardia
All species are parasitic and have elaborate life cycles, often
requiring more than one host. The best-known sporozoan is Plasmodium falciparum, the causative organism of malaria.
Myxomycophyta-no
known use
The most dramatic effect of dinoflagellates on life around them comes from the coastal marine species
which "bloom" during the warm months of summer. These species reproduce in such great numbers that the water may
appear golden or red, producing a "red tide". When this happens many kinds of marine life suffer, for the dinoflagellates
produce a neurotoxin which affects muscle function in susceptible organisms. Humans may also be affected by eating fish or
shellfish containing the toxins. The resulting diseases include ciguatera (from eating affected fish) and paralytic shellfish
poisoning, or PSP (from eating affected shellfish, such as clams, mussels, and oysters); they can be serious but are not usually
fatal.
A. Very few euglenoids have been grown in axenic culture, and euglenoid culture media are generally
very nutrient rich
II. Economic Importance
Although an indicator group for disgusting environmental conditions, euglenoids
are generally harmless
other fungi, Ascomycota are heterotrophs and obtain nutrients from dead or living organisms
(Griffin, 1994; Carroll and Wicklow, 1992). If water is present, as saprotrophs they can consume almost any carbonaceous substrate,
including jet fuel (Amorphotheca resinae) and wall paint (Aureobasidium pullulans), and play their biggest role in recycling
dead plant material. As biotrophs, they may form symbioses with algae (lichens), plant roots (mycorrhizae) or the leaves and
stems of plants (endophytes). Other Ascomycota (Ceratocystis and Ophiostoma) form symbiotic associations with an array of
arthropods, where they can line beetle galleries and provide nutrition for the developing larvae. In return, the beetles maintain
a pure culture of the fungus and transport it to newly established galleries. As parasites, ascomycetes account for most of
the animal and plant pathogens including Pneumocystis carinii, responsible for pneumonia of humans with compromised immune
systems and Ophiostoma ulmi, the Dutch elm disease fungus that is responsible for the demise of elm trees in North America
and Europe (Agrios, 1988)
Some arachnid chelicerates are parasites, such as ticks and mites. They live upon the bodies
of other animals and feed on the blood, skin, or hair. Some of these carry diseases, which they pass on to the host when they
feed.
Economically, monocots are perhaps the most important organisms on earth. Our four most important foods -- corn,
rice, wheat, and barley -- all come from monocots. Bamboo and palms are a primary source of building materials and fibers
in many tropical countries. Sugar cane, pineapples, dates, bananas, and many of our familiar tropical fruits also come from
monocots.
A. Oaks, maples, and sycamore are all dicot trees, which serve as building materials.
hydrozoa- no known
use
scyphozoa-Jellyfish are not terribly important as a food source, though they are eaten in some countries. In northern
waters, large shoals several kilometers long sometimes hamper fishing by clogging nets.
True jellyfish are graceful, and
sometimes deadly creatures. Their stings may cause skin rashes, muscle cramps, or even death.
While anthozoans retain
their nematocysts, or stinging cells, and may feed on large prey or particulate food, a number of anthozoans supplement their
diet by growing symbiotic algae in their tissues
If anything, Odonata are beneficial to humans because as voracious
aquatic predators they assist in the control of insect pests.
Hemipterans also have modified piercing and sucking mouthparts;
some suck plant juices and are plant pests, while others can bite painfully.
4) In addition to providing food for
amphibians, reptiles, fishes, birds and mammals, a role which they share with most other insects, beetles play other important
roles in the environment. Many, cantharids, scarabs, byturids, and others, are pollinators). Dung beetles (scarabs, geotrupids,
and others) feed on and reproduce in the dung of herbivores, thereby removing millions of tons of dung that would accumulate
and destroy valuable pastureland and natural areas. Burying beetles (silphids) inter animal carcasses which are then used
as food by the adults and their growing offspring thereby ridding the landscape of carcasses that would otherwise contaminate
and foul the environment. Various nest-dwellers (including histerids, trogids, staphylinids) and fur ectoparasites (such as
leiodids, leptinines) rid their bird and mammal hosts of parasitic insects, such as fleas, bed bugs, and lice. Some beetles
are effective as biocontrol agents which predate plant-feeding insects. Among these are ladybug beetles (coccinellids) which
feed on aphids and scale insects. The Vedalia ladybug beetle in California reduced the scourge of the cottony cushion scale
(Icerya purchasi). Carabid beetles, such as the "caterpillar-hunters" (Calosoma, Carabus spp.) are often helpful
in reducing populations of harmful caterpillars, such as gypsy moth and budworm caterpillars. Firefly larvae (glowworms) eat
slugs and snails which damage such crops as tomatoes and lettuce.
Lepidoptera-plant pollination
aves- bird pollination.,
seed dispersal, eggs, food, control of insects
bird flu
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