Frogs :: essays research papers

Frogs are amphibians in the order Anura. The order Anura is broken down into 22 different families of frogs and toads. Although they belong to the same order, frogs and toads are different in a lot of ways. Some of the more distinct differences are their skin and where they live. Frogs usually have smooth moist skin and toads usually have dry watery looking skin. Frogs spend most of their lives in or near water and toads spend more time on land. Amphibian means "double life." Frogs and toads each have two parts to their lives: when they live on water and when they live land. A frog's life starts in the water when it is hatched from an egg as a tadpole. A tadpole looks very different from an adult frog. A tadpole has a tail, no limbs, and breathes through gills. After a while the tadpole goes through metamorphosis. During the change the frog grows limbs, the tail disappears, it uses lungs to breathe, and it doesn't have to live in water anymore. As a tadpole, the frog feeds mostly on vegetation. The tadpoles have a small rasping mouth suited especially for scraping algea from the bottom of ponds. Depending on the species, it can take a few weeks to a year or more for the tadpoles to become fully grown. Not all frogs hatch as tadpoles. Some species of frogs hatch as froglets. Froglets look just like adult frogs but are a lot smaller. Froglets don't go through a metamophosis. Most species that hatch as froglets are found in dry places. Frogs who live in dry places where rains are seasonal have to grow up quickly because a tadpole will die if their temporary pond dries up. Adult frogs can live in water or on land, but it always needs to be near water so its respiratory organs don't dry out.

Neverending Story Turning Points Essay

Turning Points Battle for the Ivory Tower In the novel The Neverending Story, the battle for the Ivory Tower between the two protagonists; Bastian and Atreyu is a very important event to the plot of the novel. They were battling for the possession of the Childlike Empress’ amulet, AURYN: Atreyu tried to defend himself with his own sword. But wielded by Bastian, Sikanda cut in two and struck Atreyu in the chest. Blood spurted from the gaping wound. Atreyu staggered back and toppled from the wall (Ende 370). The battle for the Ivory Tower is a very important event to the plot of the novel ecause one of the major characters in the story is stabbed. Bastian is so arrogant and selfish that he stabbed his own friend just so he could keep AURYN for himself and be the Childlike Emperor of Fantastica. Atreyu only took away the amulet so Bastian wouldn’t lose anymore of his memories. However, Bastian was too self absorbed to realize that Atreyu was only trying to help him. The ba ttle for the Ivory Tower is also very important to the development of Bastian as a character. Bastian went through a change as a result of the battle. He started out very angry at Atreyu:Bastian pointed his sword at the heap of flaming ruins and his voice cracked as he declared: â€Å"This is Atreyu’s doing! For I will pursue him to the end of The world! † (Ende 371-372). However, Bastian began to feel guilty about what he had done: Over and over he lived the moment when Atreyu had set the point of his sword to his chest. And for the first time he asked himself why Atreyu hesitated. Why, after all that had happened, couldn’t he bring himself to strike bastian and take AURYN by force? And suddenly Bastian thought of the wound he had inflicted n Atreyu and the look in Atreyu’s eyes as he staggered and fell (Ende 375-376). After Bastian thought about the horrible crime he had committed, he came to realize that what he did was very wrong. Atreyu hesitated bec ause he felt sympathy for his friend even after all that Bastian had done to him. Bastian changed from being angry at his friend for the damage he had caused to feeling guilty for selfishly stabbing Atreyu. The battle for the Ivory Tower also added to the message that what Bastian did to Atreyu was very wrong and he should be shameful, â€Å"His victory left him with a itter taste in his mouth, but at the same time he felt wildly triumphant† (Ende 371). What Bastian did was a very selfish and horrible thing to do to someone who is just trying to help him. This event gets across the message that although Bastian defeated Atreyu, he should be immensely dishonoured of the the horrible thing he did. The City of Old Emperors The City of Old Emperors is a very important event in the plot of the novel. In the City of Old Emperors, Bastian learns what happens to all of the humans who come to Fantastica and try to crown themselves Emperor:Bastian saw a boy with a heavy hammer trying t o drive nails into a pair of socks. A fat man was trying to past postage stamps on soap bubbles. They kept bursting, but he went on blowing new ones (Ende 381). The City of Old Emperors is a very important event in the plot of the novel because that is where Bastian learns that if he continues making wishes, he will lose all of his memories. With no memories, Bastian can’t make anymore wishes. With no more wishes, AURYN disappears. If AURYN disappears, then Bastian will end up in the City of Old Emperors with no memory of anything.The City of Old Emperors is also very important to the development of Bastian as a character. Bastian went through a change when he learned about the City of Old Emperors. He started out very confused: For a while Bastian stood motionless. He was so stunned by what he had just heard that he couldn’t decide what to do. All his plans had collapsed at one stroke (Ende 384). When Bastian realized that he was taking advantage of Moon Child’ s powers and AURYN, he thought about what he had done to Atreyu at the battle for the Ivory Tower: Bastian dug into the earth with both hands.When the hole was big enough, he unslung the sword Sikanda and put it in. â€Å"Sikanda,† he said. â€Å"I am taking leave of you forever. Never again shall anyone draw you against a friend. No one shall find you until what you and I have done is forgotten† (Ende 385). After Bastian once again thought about the horrible thing he had done to Atreyu, he discovered that the right thing to do was burying Sikanda forever. Bastian changed from being very confused and unsure of what he should do next, to someone who knew exactly what the right thing to do is.The City of Old Emperors added to the message that Bastian learned that he was using AURYN to make too many wishes: Batstian watched a man who had lathered a mirror and was starting to shave it. Once that might have struck him as funny; now it made him break out in gooseflesh (Ende 380). Because Bastian has made many wishes, he has lost a lot of memories from his own world. The sight of the man trying to shave a mirror because he had no memories, gave Bastian goose bumps because he is worried that it could happen to him. This event gets across the message that Bastian has learned that he has made too many wishes.

Solubility Product From Solubility Example Problem

This example problem demonstrates how to determine the solubility product of an ionic solid in water from a substances solubility. Problem The solubility of silver chloride, AgCl, is 1.26 x 10-5 M at 25 Â °C.The solubility of barium fluoride, BaF2, is 3.15 x 10-3 M at 25 Â °C.Calculate the solubility product, Ksp, of both compounds. Solution The key to solving solubility problems is to properly set up your dissociation reactions and define solubility. AgCl The dissociation reaction of AgCl in water isAgCl (s) ↔ Ag (aq) Cl- (aq)For this reaction, each mole of AgCl that dissolves produces 1 mole of both Ag and Cl-. The solubility would then equal the concentration of either the Ag or Cl ions.solubility [Ag] [Cl-]1.26 x 10-5 M [Ag] [Cl-]Ksp [Ag][Cl-]Ksp (1.26 x 10-5)(1.26 x 10-5)Ksp 1.6 x 10-10 BaF2 The dissociation reaction of BaF2 in water isBaF2 (s) ↔ Ba (aq) 2 F- (aq)This reaction shows that for every mole of BaF2 that dissolves, 1 mole of Ba and 2 moles of F- are formed. The solubility is equal to the concentration of the Ba ions in solution.solubility [Ba] 7.94 x 10-3 M[F-] 2 [Ba]Ksp [Ba][F-]2Ksp ([Ba])(2 [Ba])2Ksp 4[Ba]3Ksp 4(7.94 x 10-3 M)3Ksp 4(5 x 10-7)Ksp 2 x 10-6 Answer The solubility product of AgCl is 1.6 x 10-10.The solubility product of BaF2 is 2 x 10-6.