Arthropod leg
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: coxa (meaning hip, plural coxae), trochanter (compare trochanter), femur (plural femora), tibia (plural tibiae), tarsus (plural tarsi), ischium (plural ischia), metatarsus, carpus, dactylus (meaning finger), patella (plural patellae).
Homologies of leg segments between groups are difficult to prove and are the source of much argument. Some authors posit up to eleven segments per leg for the most recent common ancestor of extant arthropods but modern arthropods have eight or fewer. It has been argued that the ancestral leg need not have been so complex, and that other events, such as successive loss of function of a Hox-gene, could result in parallel gains of leg segments.
Biramous and uniramous
The appendages of arthropods may be either biramous or uniramous. A uniramous limb comprises a single series of segments attached end-to-end. A biramous limb, however, branches into two, and each branch consists of a series of segments attached end-to-end.
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Mrs. Blaileen
by: PrimusMrs. Blaileen - she was a sixth grade teacher
And she controlled the children
By using humiliation.
The target always seemed to be Donny.
He was a bit slower than the others.
When he was quite young
His mother died at the kitchen table
While choking on some food.
The fashion of the day
Was bleach and tied Levi's.
Donny decided to make some,
But he didn't know to rinse them.
So he came to school a reekin'.
Bleach stenched filled the classroom.
Mrs. Blaileen began to chastise.
She made him feel like an asshole
two feet small.
Oh what a lonely boy.
Don and Ronald
They always stuck together
For they were a bit different than the others
And they were as tight as brothers
Then Ronald moved away.
Now Steven
He was year or two younger
And he really thought he was something.
He liked to harass other children
Or anyone he found outnumbered.
Alone Don walks from fishing.
Steven and his friend they stop him.
They took his hat and they taunt him,
Pimp-slap him with a newspaper.
Don lunged forward with his fish knife
Then ran all the way home weeping.
He gave his knife to his father and
Said "I think I hurt Steve."