why is the frog's body suitable for an aquatic environment?
111141
A frog can respire in two ways- pulmonary respiration(through lungs) and cutaneous respiration(through skin).Thus under water it can respire through skin and on land, with the help of lungs.The sklin of a frog is thin and richly supplied with blood vessels to facilitate exchange of gases.It is moist and slimy for protective purposes.
1004465
the first 1 would be frogs and the 2nd one would be lizards.....simple!!\nP.S.:thanks for the 2 points!
1186677
1. amphibians don't have AMNIOTE land egg. Reptiles do.Thus amphibians lay LOTS of eggs which have HIGH mortality rates from fungus, other organisms eating them; reptiles eggs are less vulnerable to mortality and so they lay fewer and have higher rate of hatching\n2. amphibians mate with external fertilization. Reptiles have internal fertilization and mate with HEMIPENES, not penis (true penis is in mammals!)\n3. slimy skin in amphibians, so they need water env, vs reptiles have heat-dessication resistant scales\n4. Most nitrogenous wastes of amphibians are ammonia\nreptiles have very concentrated uric acid\n5. amphibians and most reptiles have 3 chambered heart, but CROCODILIANS have a partial septum in their ventricle\n6. metamorphosis in amphibians, dev in egg in reptiles\n7. reptilian skull much more solid-heavy than amphibians.  There are more bones in reptiles (radio-ulna is ONE bone in frog, tibio-fibula is ONE bone in frog.  Reptiles have the same lower leg-arm bones as us humans and are NOT fused as in amphibians. Amphibians lack ribs, reptiles with ribs.\n8. ear HOLE and external ear on reptile head. Amphibians just have the tympanic membrane there,so they don't have much of an external ear.
201123
frogs have a cloaca, a single reservoir for both urine and feces.  Fortunately in humans these are divided so we have one opening for urine and another for feces.
1155102
As we come to the vertebrates, we begin to find real efficiencies with the closed system. Fish possess one of the simplest types of true heart. A fish's heart is a two-chambered organ composed of one atrium and one ventricle. The heart has muscular walls and a valve between its chambers. Blood is pumped from the heart to the gills, where it receives oxygen and gets rid of carbon dioxide. Blood then moves on to the organs of the body, where nutrients, gases, and wastes are exchanged. However, there is no division of the circulation between the respiratory organs and the rest of the body. That is, the blood travels in a circuit which takes blood from heart to gills to organs and back to the heart to start its circuitous journey again.\n\nFrogs have a three-chambered heart, consisting of two atria and a single ventricle. Blood leaving the ventricle passes into a forked aorta, where the blood has an equal opportunity to travel through a circuit of vessels leading to the lungs or a circuit leading to the other organs. Blood returning to the heart from the lungs passes into one atrium, while blood returning from the rest of the body passes into the other. Both atria empty into the single ventricle. While this makes sure that some blood always passes to the lungs and then back to the heart, the mixing of oxygenated and deoxygenated blood in the single ventricle means the organs are not getting blood saturated with oxygen. Still, for a cold-blooded creature like the frog, the system works well. Humans and all other mammals, as well as birds, have a four-chambered heart with two atria and two ventricles. Deoxygenated and oxygenated blood are not mixed. The four chambers ensure efficient and rapid movement of highly oxygenated blood to the organs of the body. This has helped in thermal regulation and in rapid, sustained muscle movements.
461928
The males of toads (and most amphibians in general) do not have a penis or other copulatory organ, and the fertilization of eggs is external. This means that the female toad is really ovuliparous (she's not oviparous because she does not release fertilized eggs, but rather unfertilized ova). \nIn most species, mating occurs in freshwater environments (such as ponds, lakes, rivers, etc.). The males start their vocalizations and these attract the females to the pond; then the male jumps or "climbs" on top of the female and grabs her dorsally using his strong forelimbs. This embrace is called "amplexus", and the pressure exerted by the male stimulates the female to release the ova through her cloaca, which are then fertilized by the sperm from the male's cloaca.\nThe fertilized eggs are encased in a mucous-gelatinous substance (in some cases the parents can "stir" it with their legs to make it foamy, like egg white) and attached to aquatic plants or other elements so that they don't drift or float at the surface.\n\n-------------\nGoth_chick, even though the couple may seem "stuck together", they're not physically stuck as if with an adhesive, except for some species in which the male _does_ have adhesive glands in his chest and gets stuck to the female (in these cases, the male is usually much smaller than the female and needs some help to remain on top). In most toads (especially if we're talking about the _real_ toads, family Bufonidae), the male has very strong arms for the amplexus. \nSee the photograph of toads mating:\n http://www.hainaultforest.co.uk/Toad%20pair1.JPG\n(Males are usually smaller than females)\n\nThese are Microhylidae from Asia, in this case they're really "stuck", so that if you disturb them, the female will start walking carrying the male:\nhttp://www.ecologyasia.com/images-a-j/dark-sided-chorus-frogs_0018.jpg
320173
Frogs come in variety of colors but the majority of them are green. Being green when sitting on green leaves has obvious advantages if you want to avoid becoming an easy meal for some hungry predator. \n\nFrogs are not green because they have green pigment in their skin.In their skins they have three types of pigment cells (called chromatophores) stacked on top of each other. At the bottom are melanophores, containing a mostly dark pigment called melanin. These are the same cells that can make human skin various shades of brown. On top of the melanophores are iridophores, packed with highly reflective bundles of purine crystals, and on top of the iridophores are xanthophores, usually packed with yellowish pteridine pigments. In the typical green frog, light penetrates to the iridophores, which act like tiny mirrors to reflect mostly blue light back into the xanthophores above them. These cells act like yellow filters, so the light escaping the skin surface appears green to our eyes.\n\nBy manipulating all three types of pigment cells, a wide range of colors can be produced, although usually the range extends from bright green to various shades of brown and gray. In frogs, all of these changes appear to be mediated by hormones circulating in the blood. The advantage of such color change is obvious. Imagine a frog leaping from a green leaf onto a brown tree branch. Melanin moves, reflective purine crystals shift position, yellow pteridine pigments cluster or disperse, and voila, that green frog that stood out like, well, like a green frog sitting on a brown branch is now a well camouflaged brown frog.
568980
A frog jumps and a toad walks.\n\nA frog has usually wet smooth skin, which gives feeling of colder animal. And a toad has a dry skin, of different texture, like with small warts on it.\n\nThey both are very nice. However it is not advisable to touch a toad much, because this animal, if scared, may excrete a burning fluid, not good for alergic people.\n\nI live in Europe. There are much more different frogs of many colours (and toads, I think) in the world, which may be different, also from toxicologic perspective.
187973
Mmm... it could have been an escaped pet. You could try to contact your local faunal control service and let them know, I'm sure environmental agencies would be interested in knowing about any possible exotic species. \nOne popular pet tree frog is Agalychnis callidrias (originally from Central America). Did it look like this?\nhttp://www.froggyville.com/images/graphics/usenet/wild28%5B2%5D.gif
228732
Interesting question, but I think you're putting the cart before the horse. \nI could say that they don't live out of the water because their many specializations make it impossible; you've seen what happens when a whale gets beached. \n\nAnd why not turn the question around? Why not ask\n"If dolphins live in the water, why do they have lungs instead of gills?"\nThe thing is, adaptation is a phenomenon that usually shows us amazing results, such as the entire lifestyle of cetaceans (and they have many specializations for aquatic life). But a specialized or well-adapted animal is not "perfectly" fitted, because of the way evolutionary processes work. \nEvolution and natural selection can only work on the "materials" that are already there; and the lungs of mammals are not something that can be "reverted" to gills; their origin goes way back to remote ancestors of the whales. This irreversibility of _complex_ evolutionary processes is known as Dollo's "law" (and creationists love to misinterpret it). Stephen J. Gould gave a good example with the giant panda's "thumb" (this additional finger arose from one of the bones of the carp (wrist), and the real thumb of pandas is as reduced as in the rest of the Carnivora). \nEven if cetaceans where to evolve back into terrestrial animals, the results would not look like their ancestors, or probably anything that we know.
676943
Red-eyed tree frogs are prey on by snakes, large birds, and even bats.  Birds are its major predator which spurred the developement of the frogs bright red eyes.  The red eyes of the frog act as a defense mechanism. Birds can see color and the bright flash of the red eyes popping open is enough to stun potential predators.  All the frog needs to do is stall the predator for less than a second to make its escape.
683514
The freshwater biome consists of freshwater lakes, ponds, streams, springs, and rivers. These are found all over the world. Many are beautifully landscaped, but some are just downright ugly! Most all bodies of freshwater are enclosed by land, but some rivers and streams empty into the oceans at places called estuaries. Lakes and ponds are divided into three zones. The littoral zone is near the shore where plants and animals are abundant. The next zone is the limnetic zone, which is the open water next to shore, where plankton dominate the water. The last zone is the deep part of the lake/pond called the profundal zone. This is where organisms called heterotrophs, which eat dead organisms that float down from the surface. Temperatures vary in summer from 22*C – 4*C and in winter from 4*C – 0*C. In the spring and fall, the top and bottom layers mix and then the average temperature is 4*C. Streams and rivers are bodies of moving water flowing in one direction. They can be found anywhere, but their exact origin is not really known. They may start out as lakes, ponds, springs, or even melted snow. The characteristics change from the source to the mouth. The source is cooler than the mouth. The water is clearer than of lakes and ponds, and has higher oxygen levels. Freshwater animals such as trout, snails, crabs, and clams along with heterotrophs roam the waters. In the middle part of the stream/river, the width increases, it is less shaded, and more organisms including green plants and algae are found here. Towards the mouth, the water becomes murky and light can penetrate only so far. Fish that don’t loss as much oxygen as other fish, such as catfish and carp, live here. The freshwater biome is home to many beautiful and interesting fauna and flora.
319025
Yes a big problem. Ever hear of the "boiling frog"? If you throw a frog into a boiling pot of water it will freak out, try to escape, and eventually die. BUT... if you put a frog into a cool pot of water turn the burner on and let it reach a boil, the frog will fall asleep in the warming water and then die as it boils. Wake up everybody, we're warming up, don't fall asleep! P.S. all you literal jerks out there.. this is a metaphor. Frogs biologically will respond. If they are able to jump from the container when it heats up, they will. Where are we gonna jump?
545752
the snail's body needs to be moist all the time. the water not only protects the snail it also helps lubricate it. the salt absorbs the water from the snail's body.
959845
Well I have read that a frog's tongue actually is directed down its throat when not in use, this is becasue the base of the tongue is actually attached at the front of the mouth, this would give it a downward pointing orientation when inside the mouth, so it would only make sense that the tongue would be slightly upward when outside the mouth. You have to remember that it is not as soft and evolved as the tongue of a chameleon, the frog's tongue is somewhat more rigid.
578858
Question is a little vague......anatomy is structural and function is physiological, so I am not sure what your question really is; is it about anatomy or physiology or both? So RSVP:  Are you asking about the unique physiology or anatomy of amphibians?\n\nThey have many structures in common with the other tetrapod vertebrates, but also have unique structures as amphibians.  Plus each sub-class-type of amphibian (frogs-toads) vs (newts-salamanders) vs caecilians are each different.\n\nAll amphibians have their unique slimey scaleless skin through which they attain most of their oxygen and release their CO2 by diffusion, their 3-chambered heart with 2 atria and 1 ventricle, their external fertilization type reproductive system that has egg-larva-tadpole and adult.  Their respiratory system changes at each stage of development. As tadpoles they use their gills. As they metamorphose to adults,the gills are absorbed and lungs develop to breathe air although they lack a diaphragm and ribs (in most...some amphibians retain larval stage for their whole life...axolotyl). They have kidneys and bladder for excretory system; endoskeleton is bone and has most of the same bones as us, although some are fused (radio-ulna, fibulo-tibia; no skull protecting brain, unusual urostyle bone of pelvis.
627157
In most animals, the main job of the stomach is to break down large fat molecules into smaller ones, so that they can be absorbed into the intestines more easily.\n\n1. The frog has feeble, practically useless teeth unlike humans who use their teeth for mastication in digestion.\n\n2. Solid wastes from the frog's large intestine pass into the cloaca where both liquid and solid waste material leave the body by way of the cloaca and the cloacal vent.In humans liquid waste leave the body by way of the urethra. while solid waste leaves the body by way of the rectum through the anus.