Frogs are amphibians in the orderAnura (meaning "tail-less", from Greek an-, without + oura, tail), formerly referred to as Salientia (Latin salere (salio), "to jump"). Most frogs are characterized by a short body, webbed digits (fingers or toes), protruding eyes and the absence of a tail. Frogs are widely known as exceptional jumpers, and many of the anatomical characteristics of frogs, particularly their long, powerful legs, are adaptations to improve jumping performance. Due to their permeable skin, frogs are often semi-aquatic or inhabit humid areas, but move easily on land. They typically lay their eggs in puddles, ponds or lakes, and their larvae, called tadpoles, have gills and develop in water. Adult frogs follow a carnivorous diet, mostly of arthropods, annelids and gastropods. Frogs are most noticeable by their call, which can be widely heard during the night or day, mainly in their mating season.
The distribution of frogs ranges from tropic to subarctic regions, but most species are found in tropical rainforests. Consisting of more than 5,000 species described, they are among the most diverse groups of vertebrates. However, populations of certain frog species are declining significantly.
A popular distinction is often made between frogs and toads on the basis of their appearance, but this has no taxonomic basis. (Members of the anuran family Bufonidae are called true toads, but many species from other families are also called toads.) In addition to their ecological importance, frogs have many cultural roles, such as in literature, symbolism and religion, and they are also valued as food and as pets.
Etymology and terminology
The name frog derives from Old Englishfrogga, (compare Old Norsefrauki, GermanFrosch, older Dutch spelling kikvorsch), cognate with Sanskritplava (frog), probably deriving from Proto-Indo-Europeanpraw = "to jump".
A distinction is often made between frogs and toads on the basis of their appearance, caused by the convergent adaptation among so-called toads to dry environments; however, this distinction has no taxonomic basis. The only family exclusively given the common name "toad" is Bufonidae, but many species from other families are also called "toads," and the species within the toad genus Atelopusare referred to as "harlequin frogs".
The order Anura contains 4,810 species in 33 families, of which the Leptodactylidae (1100 spp.), Hylidae (800 spp.) and Ranidae (750 spp.) are the richest in species. About 88% of amphibian species are frogs.
The use of the common names "frog" and "toad" has no taxonomic justification. From a taxonomic perspective, all members of the order Anura are frogs, but only members of the family Bufonidae are considered "true toads". The use of the term "frog" in common names usually refers to species that are aquatic or semi-aquatic with smooth and/or moist skins, and the term "toad" generally refers to species that tend to be terrestrial with dry, warty skin. An exception is the fire-bellied toad (Bombina bombina): while its skin is slightly warty, it prefers a watery habitat.
Frogs and toads are broadly classified into three suborders: Archaeobatrachia, which includes four families of primitive frogs; Mesobatrachia, which includes five families of more evolutionary intermediate frogs; and Neobatrachia, by far the largest group, which contains the remaining 24 families of "modern" frogs, including most common species throughout the world. Neobatrachia is further divided into the Hyloidea and Ranoidea. This classification is based on such morphological features as the number of vertebrae, the structure of the pectoral girdle, and the morphology of tadpoles. While this classification is largely accepted, relationships among families of frogs are still debated. Future studies of molecular genetics should soon provide further insights to the evolutionary relationships among anuran families.
Some species of anurans hybridise readily. For instance, the Edible Frog (Rana esculenta) is a hybrid of the Pool Frog (R. lessonae) and the Marsh Frog (R. ridibunda). Bombina bombina and Bombina variegata similarly form hybrids, although these are less fertile, giving rise to a From Yahoo Answers
Question:There was a TV ad for, I believe, a lawn weed and feed product. It featured an animated singing frog. Does anyone know the product name ?.
Answers:it was Evergreen Lawn Feeder, sung to a Monkees tune
Question:1. What do you think is the function of the nictiating membrane, & why?
2. The abdominal cavity of a frog at the start of hibernation would be full of large fat bodies, but at the end of hibernation season it would contain very small fat bodies or none at all. How do you think the fat bodies work?
3. Structures of an animal's body that help it in it's evironment are called adaptations. Do you know any adaptations of the external anatomy of the frog? What is one of them and how does it help the frog?
4. What is one difference between the anatomy of a frog and the anatomy of a human being? How does the difference between our anatomies help us in our environment or life style?
Answers:First off you are the cutest zoologist I've ever seen. Sorry, it needed to be said.
Nicitating membrane acts like a scuba mask to protect the eyes while under water.
Fat bodies provide energy while the frog is hibernating. They get smaller because the fat is being used up.
Slimy skin helps the frog to absorb oxygen from its environment. Webbed feet help it to swim. Nicitating membrane helps to see under water.
Frogs have a cloaca, which is a common opening for excretory waste and feces. Humans don't. Frogs eliminate waste in water, we need other options. We breathe through our lungs because we are terrestrial, and they use skin, mouth and lungs because the have to be able to take in oxygen in different environments.
1 Examine the external structure of a frog. To open its mouth, use scissors to cut the sides of the mouth slightly. Look inside. Identify each body part shown in the Figure below.
2 Compare the frog to a person. Use Table 1 to record similarities and differences you observe. Also record the functions of each body part.
3 Place the frog on its dorsal (back) side. Pin the legs to the pan.
4 The frog should now be in a position that will allow you to open its body cavity. Carefully use scissors to cut through the skin and muscle from between the hind legs all the way to the lower jaw. CAUTION: use care when cutting! NOTE: Do NOT cut too deeply. You do not want to damage the internal structures.
5 Cut through the bone in the chest region with scissors. Then cut the body wall toward the sides (see figure). Fold the tissue to each side and pin it to the dissecting pan.
6 Observe the internal organs. Some organs will be hidden from view. Those organs on top must be moved to the side in order to see all parts. NOTE: Female frogs are often filled with eggs. Use forceps to carefully remove the eggs in order to see the organs.
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Wait! Please read this before you begin the actual dissection:
Unlike humans, frogs don't store fat next to the skin. Frogs store winter fat in fat bodies, found inside the body cavity. If your frog was collected late in the year, the body cavity might be full of orange fat bodies.
Now you are ready to being the actual dissection. Please be respectful of your lab partners and of the specimen you are about to explore, observe, and learn from.
Take extra care with your dissecting tools. Your scissors are your most important tool, but be sure to handle them carefully and always double check before cutting.
1. Begin by pinning your frog on its back to the dissecting pan.
2 Follow the diagram on the right, and make the cuts shown through the thin belly skin.
You'll notice that skin is paper thin, and not tightly attached to the muscle underneath.
You will also find hard abdominal muscles right under the skin.
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3. Pin back the skin and open the body cavity the same way you opened the skin.
4. Now pin back the abdominal muscle to expose internal organs.
5. Push the 3-lobed liver to the left to expose the esophagus, which runs back from the mouth to the large, J-shaped stomach.
6. Now cut the esophagus as close to the mouth as possible.
7. Look for the stomach, which consists of a large, anterior cardiac portion and a smaller, posterior pyloric portion that ends at the pyloric sphincter. This circular muscle opens and closes the bottom of the stomach.
8. Now look for the first part of the small intestine. Called the duodenum, it is directly below the pyloric sphincter.
9. Behind the duodenum is the elongated and coiled ileum, which connects the small intestine to the large one.
10. Find the large intestine by looking for an obvious expansion of the alimentary canal in the posterior region of the body cavity.
11. Look for the gall bladder on the dorsal surface of the right lobe of the liver.
12. Now find the spleen. It is a dark, spherical organ in the intestinal mesentery, below the kidneys.
PAGE 4 of 7
LOCATE each of the organs. Check the box to indicate that you found the organs.
Fat bodies - spaghetti shaped structures that have a bright orange or yellow color, if you have a particular fat frog, fat bodies may need to be removed to see other structures. Usually they are located just on the inside of the abdominal wall.
Peritoneum - A spider web like membrane that covers many of the organs, you may have to carefully pick it off to get a clear view.
Liver - The largest structure of the body cavity. This brown colored organ is composed of three parts or lobes: the right lobe, the left anterior lobe, and the left posterior lobe. The liver is not primarily an organ of digestion; it does secrete a digestive juice called bile. Bile is needed for the proper digestion of fats.
Heart- at the top of the liver, the heart is a triangular structure. The left and right atrium can be found at the top of the heart. A single ventricle located at the bottom of the heart. The large vessel extending out form the heart is the conus arteriosis.
Lungs - locate the lungs by looking underneath and behind the heart and liver. They are two spongy organs.
Gall bladder - lift the lobes of the liver, there will be a small green sac under the liver. This is the gallbladder, which stores bile. (Hint: it looks like a booger).
Small intestine - leading from the stomach, the first straight portion of the small intestine is called the duodenum; the curled portion is the ileum. The ileum is held together by a membrane called the mesentery. Note the blood vessels running through the mesentery; they will carry absorbed nutrients away from the intestine. Absorption of digested nutrients occurs
Answers:Son, you have too much time on your hands.
Question:Amphibians live in a variety of habitats. Generate hypothesis as to why this is true. What feature of the frog's physiology prevents its successful adaptation to marine habitat?
Answers:they absorb water ozmotically through their skin. So the fact that it is salt water would cause them to have an overdose of salt in their system.
Frog Sex :Frogs mating, birds singing, spring is in the air...frogs dont actually have sex mating is by external fertilization...it just looks like sex
The Princess and the Frog Movie Trailer :Disney goes back to the princess well once again with The Princess and the Frog, a movie that's about pretty much what it says, a princess and a frog. Featuring major names like Oprah Winfrey and Terrence Howard, The Princess and The Frog takes us back to the New Orleans French Quarter at the dawn of the twentieth century--often called the Jazz Age. A visiting prince finds himself turned into a frog by an evil witch doctor, and believes that the only way he can become human again is to receive a kiss from a princess. So when he finds Princess Tiana, he believes his troubles are over...but are they? Check out the trailer! It'll be hopping onto screens this December, but what do you think about this one? Is it good to see Disney finding their roots again, or is it just more of the same? Hit the comments section below and tell us what you think. Thanks for watching! The Princess and the Frog Cast: Anika Noni Rose, Terrence Howard, John Goodman, Keith David, Jim Cummings, Jenifer Lewis, Oprah Winfrey The Princess and the Frog movie trailer is provided by Walt Disney Pictures. The Princess and the Frog opens in US theaters on November 25th, 2009. The Princess and the Frog is directed by John Musker and Ron Clements.