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Animals

I like invertebretes. I really do. Despite thier literal and metaphorical lack of backbone, I think I've enjoyed invertabretes the most out of all diversity. My girls and I really seem to be fond of Cnidarians, which we will learn about a bit later on, and I personally enjoy reminicing about fred rolling around on the table as a mollusca. All in all, good memories of invertabretes in class. So when I was chosen as the one to do invertabrete diversity (I'm going to skip the part where I declared it myself just to save time) I got pretty geeked up - just cause I like them. (Plus I have them memorized.)

Porifera:

SPONGES - yes I do declare, its what you just used to wipe up that spaghetti dinner and clean up the sink. Sponges are aquatic animals that pretty much mark the transition phase from unicellular to multicellular life. Sponges are pretty un-complex, and mostly live in salt water. Random fact: of the 10,000 species of sponges, only about 150 species live in fresh water. Adult sponges free flow in the water, which is terribly useful to them, because they are filter feeders, which means they derive food out of the water that flows through thier body.

Cnidaria:

JELLYFISH! One of our FAVORITES as a group, hence the picture taken at spring break! This Phyla consists of freshwater hydra, jellyfish, and corals which go through a transition in body forms. The medusa stage (bell-shaped) is specialized for swimming and the polyp stage (vase-shaped) is specialized for a sessile life. All members of the phylum have these two stages at one time in their life, even though the medusa stage may be found only as an embryo. All cnidarians have tentacles containing cnidocysts and nematocysts, specialized stinging cells for defense and capturing food. When they wash up on the beach, they tend to attract nerds yelling "ooh! come see the cnidarian!"

Nematoda:

Ahh. WORMS. The hint in taboo is forever "dirt" to which I have most definitly formed a neural pathway from annalids, plattyhelmenthes and nematods to connect right when I hear the word dirt, which I cant imagine actually being helpful in the future. But whatever. Roundworms have a long, slender body that tapers at both ends. They range in length from 1 millimeter to 4 feet in length. This phylum is the first to have a digestive tract with two openings, which is a major advancement over the phyla up to this point. The vast majority of these animals are free-living, but there are about 150 species that are plant and animal parasites. It has been said that if all things except roundworms were erased from the earth, one could recognize where plants, animals, and even cities were by looking at the roundworms.

Mollusca:

::Insert picture of fred on table acting like a clam:: Snails, clams, squids and octopi are the first animals with a true coelom, a hollow, fluid-filled cavity completely surrounded by the mesoderm. The phylum is divided into three diverse classes.
Gastropoda: most members of this class have a one-piece, external shell. Gastropods include snails and slugs.
Bivalvia: members have an external shell divided into two halves that are connected by a hinge. Bivalves include clams, oysters, and scallops.
Cephalopoda:these marine mollusks are the most advanced group in the phylum. Their nervous and circulatory systems are highly advanced and they have an internal shell supporting the body. Octopus and squids are cephalopods, including the giant squid - the world's largest known invertebrate.

Annelida:

DIRT! WORMS! Segmented worms are more advanced than roundworms and have several visible characteristics that distinguish them. They are named for the many body segments that make an annelid look like it is composed of a series of "rings". Unlike roundworms, the segmented worms have an obvious head and tail. All segmented worms have one of two types of structures extending from their bodies that are used for locomotion. Most annelids have hair-like bristles known as setae and some have fleshy protrusions called parapodia.

Arthropoda:

BUGS! Three-fourths of all animal species, including spiders, crayfish, and insects, are arthropods. This phylum is composed of a very diverse group of animals that are bilaterally symmetrical. The following characteristics have allowed arthropods to adapt to almost every environment on Earth:
Jointed appendages: the phylum name means "jointed foot". All the appendages (body extensions) of arthropods are jointed, giving them a wide range of controlled motions.
Exoskeleton: the exoskeleton provides support and protection. It is composed of three layers that are secreted by the epidermis.
Segmented body: the segments in the arthropod body make movement possible, even with the hard exoskeleton.

Echinodermata

Starfish, (otherwise and more pollitically correctly known as SEA STARS) sand dollars, and sea urchins are found in marine environments ranging in depth from shallow tide pools to 10,000 meters. Most of the 7,000 species of echinoderms have a type of radial symmetry called pentaradial symmerty, in which the body parts extend from the center along five spokes.
In addition to their radial symmetry, echinoderms have three other major characteristics that are not shared by any other invertebrate phylum:

They have an endoskeleton composed of calcium carbonate plates known as ossicles. These may be attached to spines that protrude through the skin. The phylum name echinoderm means "spiny skin".
They have a water-vascular system - a network of water-filled canals inside their body.
They have many small, movable extensions of the water-vascular system called tube feet, which aid in movement, feeding, respiration, and excretion.

And this will conclude our overview of the importance of INVERTABRATES, and also a quick look into the word associations that Katie loves to take part in!

VERTEBRATES OMG it is SO EXCITING

THere are six main divisions of vertebrate animals they are...

the CHONDRICHTHYES
the sharks and cartilaginous fishes!!! they have a lot of cartiladge so they can swim easily. they are bendy!

the OSTEICHTHYES
these are the bony fishes. they are the most numerous and vary greatly in size. their bone matrix of calcium phosphate gives them their "bony" name.

the AMPHIBIA
these are the amphibians, frogs, salamanders etc. they live on land and in water. a very versatile class.

the REPTILIA
REPTILES!!! these are the snakes and lizards that are closely related to birds and that give many mammalians the heeby jeebies.

the AVES
birds! the wild winged wonders. they have a unique honeycomb bone structure that makes them lightweight enough to fly, and gives them an aerodynamic body structure.

and the MAMMALIA the humans, animals, almost all organisms that reproduce placentally. they are the most complex organisms.

During development, cell layers form and make specific tissues and organs in the adult. Diploblastic animals have two layers, an outer ectoderm and inner endoderm. Triploblastic animals have a third layer called the mesoderm between the other two layers.

There are two patterns of development that divide all animals (other than sponges) into two groups, the protostomes and deuterostomes. Protostomes are formed mouth first; deuterostomes are formed anus first and a second opening becomes the mouth. As early as the first phase of development, cleavage,one can distinguish between protostomes and deuterostomes.

During gastrulation, a body cavity forms in most groups of animals.

So. you may be wondering. HOW DID ALL OF THESE COMPLEX ANIMALS BECOME THE WAY THEY ARE TODAY, soo complex and everything... yes well ill tell you.
looking at a "family tree" of sorts we can observe the progression from simple to complex organisms in the kingdom animalia.
a simple silly ancestral protist became multicellular somewhere along the way, and branched off into two categories of organisms, those with true tissues, and those without true tissues. the next branching of the tree which led to even more complex organisms was the separation of radially symmetrical organisms, such as the cnidarian, and the bilaterally symmetrical organisms, such as the platyhilmenthes. the next branching out of further complexity is between the presence or absence of a body cavity. the coelomates went in one direction, and the acoelomates went in the other. The coelomates had the advantage of a body cavity or two, or ten, and they evolved further into the roundworms, flatworms, and ribbon worms. The next big step in the evolutionary tree was the parting of the dueterostomes and protostomes. The dueterosomes formed anus first which gave them an advantage evolutionarily so they are the most complex organisms in the kingdom animalia. they protostomes are pretty complex, but because they form mouth first, they are still lacking in complexity in comparison to the dueterostomes. see the picture of the family tree for a visual aid.