when lizards cut their tail it grows up but if a human being cuts it's hand it does not grow,why?
613503
because humans aren't lizards
350452
no alligators do not show regeneration.\nanimals like starfish do,when they are cut they regenerate that part of the body and it grows back.\nhowever alligators do not have this property
139900
No, the tail is not poisonious. The head isn't poisonious either, it's venomous, but that's just a technical detail (venom is injected with fangs, stinger, etc, poison isn't). But centipedes have two fangs on the bottom of the head. They can inflict quite a bit, especially the larger species. There could be some reason for people to think the tail is venomous though, there are two long "tails" at the end that look quite bad, but aren't. The tail also looks like it has antenna, so it can be confused with the tail. Also, anyone foolish enough to pick a centipede up by the tail is very likely to get bitten anyways. Centipedes are very fast and can bend backwards on themselves. But it is not the tail that is venomous.
589538
IT IS A VESTIGIAL ORGAN I.E. AN ORGAN THAT DOES NOT HAVE ANY FUNCTION IN OUR BODY BUT HAS SOME FUNCTION IN OUR ANCESTORS BODIES SUCH AS APES AND MONKEYS. IT DOES NOT HAVE TO DO ANYTHING WITH THEIR TAILS BUT DOES WITH THEIR STOMACH.\nEG: IN BIRDS THE NICTATING GLANDS OF EYES PROTECTS THEM FROM WIND WHEN THEY FLY BUT OUR NICTATING GLANDS ARE USELESS,WE INSTEAD HAVE TO USE SUN GLASSES.\nTRUST ME I JUST GAVE MY BIO. EXAM.
905462
Most parts of a male are typically bigger than the same parts on a female (not all though, females typically have wider hips for example).  This phenomenon is known as sexual dimorphism.  The most likely causes of sexual dimorphism in humans are  competition between males for females (the bigger you are the better you are at beating other men, both in a physical fight and in a bluff) and female mate choice, where females tend to pick taller, broader men for partners.  Both of these factors have led to evolutionary pressure on males to get bigger.  The mechanism by which this occurs during development is closely modulated by testosterone.  The more testosterone a man has, the taller he grows, the broader his shoulders are, the bigger his hands and feet are and the squarer his jaw is.\nSome more interesting things about the hands of men and women, is that women tend to have narrower palms and longer fingers and men tend to have wider palms and shorter fingers.  Another interesting quirk is that the more testosterone a baby boy is exposed to in the womb of his mother (yes, women have testosterone too, just not as much as men!) the longer his second digit (pointer finger) will be compared to his fourth digit (wedding ring finger).  Hopefully these will be some interesting facts to put on a science fair project!
616561
The scales- Same structure, shape, and composition- In fact, a related function, since sharks will brush the sides of their body by interesting possible food items to scrape off a little (of your skin, for example) in order to "taste" it with special sensors in the skin.  Generally, if a shark does this with a human, they will *not* attack further.
1104290
This type of reaction is caused by the nerves in the tail. The lizard Sheds its tail in an attempt to get away from predators. The movement in the tail is suppose to detract attention from the fleeing lizard.
309067
The hair follicles are different on each part of your body.  All areas grow at different rates.  And it does keep growing on your arms, just very slowly.  \n\nTry shaving your arms or waxing them.  You'll find that the hair comes back, but to that same length.  So it is growing.
935334
You friend is wrong. Some worms continue to live as two worms if you cut them up, or the living part grows again.\n\nBut if you cut up a snake, you break its backbone. No creature survives a cut up back bone. Yes, it dies.
31307
Each person has a  different limit to how long his or her hair can grow, but don't reach it since it is generally socially unacceptable. Most people can't grow hair much past their tushes...
577448
It's bad if the lizard bit your right foot and it was a poisonous one. It's good if the lizard didn't bite you and it was a poisonous one.
832561
If you mean 'Iguana', then: lizard, cold blooded, grows by sheading skin
974358
lizards can regenerate tails\nnewts and salamanders can regenerate\n\nPlanarians are flat worms. If cut into pieces, each piece can grow into a new worm.\n\nSea cucumbers have bodies that can grow to be three feet long. If cut into pieces, each one can become a new sea cucumber.\n\nSharks continually replace lost teeth. A shark may grow 24,000 teeth in a lifetime.\n\nSpiders can regrow missing legs or parts of legs.\n\nStarfish that lose arms can grow new ones; sometimes an entire animal can grow from a single lost arm.
397831
It depends on the type of rattlesnake, how well it has been eating, and on the individual characteristics of that particular snake.\n\nRattlesnakes add a "button" to their rattle each time they shed their skin.  Rattlesnakes, as all snakes, shed their skin after they grow a certain amount.  The rate of growth is not constant throughout their life.  They grow very fast from birth, but then slow down as they reach maturity.  If they live in an area where food is scarce, or difficult to catch, they will not grow as fast as one for whom food is plentiful and easily captured.\n\nBecause of the unconstant growth rate, counting the rattles is not an effective method to predict a snake's size, nor it's age.  Also, rattles can break, partially or completely.  An island off of South America boasts a population of rattlesnakes that don't have any rattles at all.  They have evolved to be brittle, and break off immediately after each shed.  This trait was selected, because the main prey item on this island isn't rodents, but birds, which must be hunted in the trees where they live.  Can you imagine trying to sneak up on an alert, very fast-reacting bird when your rattle gives you away everytime the wind moves the branch you're on?
335943
Okay.... blood, in general, no matter what species it comes from is blue when it is oxygen deficient (in our veins)... and red when it has oxygen (in our arteries)... if a snake is cut open (while alive.... or right after being killed) then all of the blood will be red, regardless if you hit a vein or artery..... because when the blood is given oxygen it turns red.\n\n-Z
828421
Animals are supported by a skeleton, made of bone.  Plants don't have skeletons, they use a cell wall to give them support.  Such walls wound make movement impractical.
1082915
cool question!\n\nno reptiles do not suffer from dwarfism in the true sense that humans do \n\nbut they can have retarded or stunted growth due to stress or poor food etc either when they are in the egg or subsequent to that