پاسخ : سیستماتیک. دمین یوکاریوت ها ؟؟؟
من دیروز داشتم raven میخوندم
تاجایی که یادمه نوشته بود دیگه پروتیستا به علت اینکه مونوفیلتیک نیست دیگه یک فرمانرو رسمی نیست و به صورت غیر رسمی یک "ابر فرمانرو" دسته بندی میشه.
اینم از کتاب هیکمن گرفتم امیدوارم به دردتون بخوره
---- دو نوشته به هم متصل شده است ----
الان رفتم ریون رو بگردم ببینم کجاش نوشته بود نتونستم دقیق پیدا کنم!!!
در تایید حرف بالام هیچ تضمینی نمیکنم:4:
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این رو هم بخونید تو هیکمن بود شاید به دردتون بخوره:
MAJOR DIVISIONS OF LIFE
From Aristotle’s time to the late 1800s, every living organism was
assigned to one of two kingdoms: plant or animal. However,
the two-kingdom system had serious problems. Although it was
easy to place rooted, photosynthetic organisms such as trees and
herbs among the plants and to place food-ingesting, motile forms
such as insects, fi shes, and mammals among the animals, unicellular
organisms presented diffi culties (see Chapter 11). Some
forms were claimed both for the plant kingdom by botanists and
for the animal kingdom by zoologists. An example is Euglena
(p. 225), which is motile, like animals, but has chlorophyll and
photosynthesis, like plants. Other groups, such as bacteria, were
assigned rather arbitrarily to the plant kingdom.
Several alternative systems have been proposed to
solve the problem of classifying unicellular forms. In 1866
Haeckel proposed the new kingdom Protista to include all
single-celled organisms. At first bacteria and cyanobacteria
(blue-green algae), forms that lack nuclei bounded by
a membrane, were included with nucleated unicellular
organisms. Finally, important differences were recognized
between the anucleate bacteria and cyanobacteria (prokaryotes)
and all other organisms that have membrane-bound
nuclei (eukaryotes). In 1969 R. H. Whittaker proposed a fi vekingdom
system that incorporated the basic prokaryoteeukaryote
distinction. The kingdom Monera contained the
prokaryotes. The kingdom Protista contained the unicellular
eukaryotic organisms (protozoa and unicellular eukaryotic
algae). Multicellular organisms were split into three kingdoms
by mode of nutrition and other fundamental differences in
organization. The kingdom Plantae included multicellular
photosynthesizing organisms, higher plants, and multicellular
algae. Kingdom Fungi contained molds, yeasts, and fungi
that obtain their food by absorption. Invertebrates (except the
protozoa) and vertebrates compose the kingdom Animalia.
Most of these forms ingest their food and digest it internally,
although some parasitic forms are absorptive.
These different systems were proposed without regard to the
phylogenetic relationships needed to construct evolutionary or
cladistic taxonomies. The oldest phylogenetic events in the history
of life have been obscure because the different forms of life
share very few characters that can be compared among them to
reconstruct phylogeny. Recently, however, a cladistic classifi cation
of all life-forms has been proposed based on phylogenetic
information obtained from molecular data (the nucleotide base
sequence of DNA encoding ribosomal RNA). According to this
tree ( Figure 10.11 ), Woese, Kandler, and Wheelis (1990) recognized
three monophyletic domains above the kingdom level:
Eucarya (all eukaryotes), Bacteria (the true bacteria), and Archaea
(prokaryotes differing from bacteria in membrane structure and
ribosomal RNA sequences). They did not divide Eucarya into
kingdoms, although if we retain Whittaker’s kingdoms Plantae,
Animalia, and Fungi, Protista becomes a paraphyletic group ( Figure
10.11 ). To maintain a cladistic classifi cation, Protista must
be discontinued by recognizing as separate kingdoms all of the
labelled branches of Eucarya as shown in Figure 10.11 .
Until a few years ago, animal-like protistans were traditionally
studied in zoology courses as animal phylum Protozoa.
Given current knowledge and the principles of phylogenetic
systematics, this taxonomy commits two errors; “protozoa” are
neither animals nor are they a valid monophyletic taxon at any
level. Kingdom Protista is likewise invalid because it is not
monophyletic. Animal-like protistans, now divided into seven
or more phyla, are nonetheless of interest to students of zoology
because they provide an important phylogenetic context
for the study of animal diversity.
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این هم از ویکیپدیا:
بد نیست این جارو هم ببینید:
http://en.wikipedia.org/wiki/Protist