Kingdom Animalia
Animals are complex multicellular heterotrophs. Their cells are mostly diploid, lack a cell
wall, and are organized as tissues. In addition, their zygotes develop through several
stages. Theses adaptations have enabled animals to be successful in different habitats. The
specialized tissue called muscle enables animals to move about readily. The ability of
animals to move more rapidly and in more complex ways than members of other
kingdoms is one of their most interesting characteristics. A remarkable form of movement
unique to animals is flight, an ability that is well developed among both insects and
vertebrates. Movement enables animals to avoid predators and to look for food and mates.
Most animals reproduce sexually. In animals, cells formed in meiosis function directly as
gametes. The haploid cells do not divide by mitosis first, as they do in plants and fungi,
but rather fuse directly with one another to form the zygote. The zygote then gradually
develops into an adult, going through several developmental stages.
Almost all animals (99 percent) are invertebrates; that is, they lack a backbone. Of the
more than 1 million living species, only about 42,500 have a backbone; they are referred
to as vertebrates. The animal kingdom includes about 35 phyla, most of which live in the
sea. Far fewer phyla live in fresh water, and fewer still live on land.
Kinds of Animals (Characteristics of Phyla)
Animals are very diverse in form. They can range in size from 0.5mm microscopic mites
(Demodex follicularum) that live on your skin to enormous whales, which are vertebrates,
and giant squids, which are invertebrates. Blue whales can reach a length of 30m and
weigh up to 220 tons. The many kinds of animals can be grouped by phylum.
Phylum Porifera: Name means "pore-bearing".
This phylum consists of the sponges. All are aquatic and almost all are marine.
Are the only animal without tissues, but specialized cells, they are multicellular, they have
no nervous system or sense organs. They are sessile as adults, but have a free swimming
larva.
Sponges often are abundant in reef ecosystems. They somehow are protected from
predators by their spicule and bad taste
Phylum Cnidaria: Name comes from the Greek knide- meaning "nettle".
This phylum consists of the jellyfish, hydra, sea anemones, corals, sea pens, sea wasps,
and box jellyfish. Cnidarians are mostly marine animals. Cnidarians have no head, no
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Animals are complex multicellular heterotrophs. Their cells are mostly diploid, lack a cell
wall, and are organized as tissues. In addition, their zygotes develop through several
stages. Theses adaptations have enabled animals to be successful in different habitats. The
specialized tissue called muscle enables animals to move about readily. The ability of
animals to move more rapidly and in more complex ways than members of other
kingdoms is one of their most interesting characteristics. A remarkable form of movement
unique to animals is flight, an ability that is well developed among both insects and
vertebrates. Movement enables animals to avoid predators and to look for food and mates.
Most animals reproduce sexually. In animals, cells formed in meiosis function directly as
gametes. The haploid cells do not divide by mitosis first, as they do in plants and fungi,
but rather fuse directly with one another to form the zygote. The zygote then gradually
develops into an adult, going through several developmental stages.
Almost all animals (99 percent) are invertebrates; that is, they lack a backbone. Of the
more than 1 million living species, only about 42,500 have a backbone; they are referred
to as vertebrates. The animal kingdom includes about 35 phyla, most of which live in the
sea. Far fewer phyla live in fresh water, and fewer still live on land.
Kinds of Animals (Characteristics of Phyla)
Animals are very diverse in form. They can range in size from 0.5mm microscopic mites
(Demodex follicularum) that live on your skin to enormous whales, which are vertebrates,
and giant squids, which are invertebrates. Blue whales can reach a length of 30m and
weigh up to 220 tons. The many kinds of animals can be grouped by phylum.
Phylum Porifera: Name means "pore-bearing".
This phylum consists of the sponges. All are aquatic and almost all are marine.
Are the only animal without tissues, but specialized cells, they are multicellular, they have
no nervous system or sense organs. They are sessile as adults, but have a free swimming
larva.
Sponges often are abundant in reef ecosystems. They somehow are protected from
predators by their spicule and bad taste
Phylum Cnidaria: Name comes from the Greek knide- meaning "nettle".
This phylum consists of the jellyfish, hydra, sea anemones, corals, sea pens, sea wasps,
and box jellyfish. Cnidarians are mostly marine animals. Cnidarians have no head, no
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