CLASSIS AMPHIBIA

Practicum Report Zoology Vertebrate
3rd Practicum

Title : Classis Amphibia
Introduction
Amphibian is derived from the Greek meaning Amphi double and bios meaning life. So amphibia are animals that live with two forms of life, first in fresh water and then continued on the ground. In amphibia there is a change in the respiratory and locomotor organs. On land these animals no longer needed so that the gills for respiration and stimulates the formation of reduced lung. On changes in locomotor, while in the water body amphibia be light because of the upward buoyant force and allow for movement of the fin, but when the land will be heavier body so that the fins can not withstand the weight of the body. Therefore, it is necessary legs to walk, this leg is assumed as a modified form of the pinna pectoral and pelvic pinna in Pisces. Amphibian metamorphosis can be seen in the image below (Andi, 2010).

Image 1. Frog Metamorphic


Amphibians have the characteristics, namely as follows:
Her body was covered skin slimy
It is a cold-blooded animal or Poikilotherm
Amphibious have a heart that consists of three rooms, two porches and one cubicle
Have two pairs of legs and on each leg there are swimming membranes between the toes and legs function to jump and swim in the water
The eyes have additional membrane called niktitans membrane function while diving in the water
Breathing while still tadpole form of gills, as an adult breathing apparatus in the form of the lung and skin
The nose has a valve that serves to prevent water from entering into the oral cavity when diving in the water
Breed by releasing eggs and fertilized by the male outside its mother's body, which is called external fertilization
Not having nails and claws, but there are some members that the tip of his finger amphibia experience penandukan shaping nails and claws, for example Xenopus sp.
The skin has two glands are glands or glandular mucosa and berbintil (usually poisonous)
Has the auditory system, in the form of auditory canal and tympanum known as tympanum
Has the tooth structure, namely the maxillary teeth and the teeth of the palate.
Amphibia members consist of 4 orders namely Urodela (Salamander), Apoda (Caecilia), and Anura (frogs and toads), Proanura (already extinct).
Order Apoda (Gymnophiona)
The General characteristics of this Order is have no legs so called Apoda. The body resembles a worm (roundworm), segmented, not limbed, and reducing tail. This animal has a compact skin, eyes reduced, covered by skin or bone, retina in some species function as photoreceptors.

Images 2. Example animal of Order Apoda or Gymnophiona
Order Urodela / Caudata
This Order has the characteristic shape of an elongated body; limbs and tail have and do not have the tympanum. The body of this order can be distinguished between the head, neck and body. Some species have gills and others breathe with lungs. In this part of the head there is a small eye and in some kind of order are the eye is reduced. Members of the order Urodela live on land but cannot be separated from the water. Distribution species covering North America, Central Asia, Japan and Europe.

Images 3. Example animal of Order Urodela or Caudata
Order Anura
Anura has characteristics that are influenced by the habits of life and a place of life, in addition to the structure of the framework that indicates the characteristics of primitive and advanced characteristics. This structure appears in the shoulder girdle structure, namely the shape and firmisternal arsiferal shoulder girdle. On the shoulder girdle arsiferal characterized by overlapping the scapula bone (primitive traits), for example in Leiopelmatidae and Discoglossidae. While the shoulder girdle firmisternal characterized by non-overlapping scapula bone that normally occur in modern frogs (Larasati, 2010).

Image 4. Anura Order Morphology

Image 5. Anura Ordder Anatomy

Purpose of Practicum
Observing the characteristics of both morphology and anatomy of one instance of the class Amphibian and the morphology of Bufo Sp. Or Rana Sp.
Classify organisms into the levels of classification (categories) based on their characteristics.
Deepening the understanding of the various organ systems owned by a group of Frog (Amphibian).

Tools / Materials / Resources
Tools:
Board section
Complete surgical equipment (including iron cutter and scissors with sharp edges)
Needle blotter
A magnifying lens or microscope stereo
Cardboard / manila paper, plastic, glue, Styrofoam
Materials:
Species of frog Bufo Sp. or Rana Sp.
Cornstarch
Carbolic (for disinfected)
Alcohol 70% or chloroform, borax (for killing and preserving)
Procedure
Before starting the main activities, prepare all the necessary equipment. To kill the specimen, enter chloroform with cotton into killing-jar. Then insert some frogs and tightly closed. Wait a few minutes. After the frog killed, take and put on a board or box section. Perform the following activities:
Inspectio: observing specimens, alive or dead. Noting that there are organs in the caput, truncus, and observe the extremitasnya. Describing the outer structure and name parts. Opened his mouth wide, observing the parts are in ramioris, then describe. Checking the distinguishing characteristic between males and female frogs.
Sectioning: put the specimen such that the ventral part of the body facing up. Nailing each palm of his hand with a pin. Doing surgery carefully with scissors or a knife section start at the midline of the sternum on. To facilitate surgery, skin slightly removed using tweezers, then cut with slowly toward cranial up in the middle of the mandible. Then proceed to the caudal direction, until in the groin, and continued cuts to the thighs and arms. Lipatkan this skin laterally. At the time of this leather cutting, notice:
Saccus lymphaticus subcutaneus
Septa as a barrier between saccus lymphaticus
To open the abdomen, abdominal muscle cut from posterior to anterior along the median line to cut the sternum. Cut is continued to the side and then the muscles abdomen opened to the side so it looks the organs in the abdominal cavity.
Noting the organs contained in the abdominal cavity. The way these work is done to learn every organ system in the body of the animal in question. Began to pay attention to the topography of organs, then draw and name the parts.
After the lifting of each organ system ranging from Systema digestive, respiratory Systema, Systema circulatorius, urogenital da Systema Systema nervorum. In this activity, should be careful in order not to cut too bantak network of blood is spilled yng mengakibatakan observation difficult. If this happens wipe the blood by using cotton. Describe and name the parts of each organ system has been appointed until the entire system organ in the abdominal cavity was observed.
To learn nervorum system, especially the spinal nerves. Removing the entire contents of the abdominal cavity so that the vertebral column terlhat clear. Between meetings spinal segments will come out to the left and to the right of the spinal nerves creamy. Viewing:
Branchialis plexus, and plexus ischiococcygeus. To view the brain, scalp first removed and then carefully cut cranium to be carefully then brain can be removed. Observing the parts of his brain.
To observe the muscle system, must be taken from the first step to the skin of the abdomen open. Surgery followed to the thighs, calves and upper arms. Subsequently turn the frog's body so that the dorsal part of the body facing up. Perform surgery such as the ventral part of the body, so that the entire skin peeled off. Observing muscle parts that can be seen from the outside. After identifying the muscles of the surface, then cut 3 pieces of muscles located in the ventral part of the right foot, to choose the muscles inside. Noting the large tendon Achiles.


Result

Discussion
In this third practicum, we've execution about the animal that in the neighborhood called frog. This animal from the general characteristic is grouped into class of amphibian. In this world, the most type of frog that we found is in two types. First type is the frog that has smooth skin with web among its digity and its leg fingers. Second type is the frog has rough skin and smooth web among digity and leg fingers and also has caws on fingers. In bahasa, the smooth skin one called "katak" and the rough one called "kodok". Both of this frog type have same characteristic that make them include into the class of amphibian. From the word of amphibian is from two greek words, those are amphios that mean two worlds and bios mean living or organism (Campbell, 2010). Frog is the type of animal that have live phase in two worlds, when the frog still in larva phase or we call it tadpole, it lives in the water, especially fresh water until it has their complete extremities or limb. After the adult phase, it lives in the terrestrial but still through their part life in the water such as for reproduction and take off the eggs (Irnaningtyas, 2014). The other characteristics will be explained on the system organ of the frog in the next paragraph.
In this practicum, as always we start our observation by inspected the morphology of frog that we found around our house. The frog body divided to dorsal and ventral area. The ante-posterior body side separated also into two part, those are cephalic and truncates. The anterior is about the cephalic from the ventral, we found the outer of mandible muscle or we call it musculi myhyoideus's skin is rough where the granules is reddish. The dorsal side we found many parts that important to support the frog living. The first side that we found is rima oris or mouth. The frog has very wide rima oris where's in the inside we found lingua or tongue that function to catch the prey. Goes to the posterior side we found big eyes, it has one eye in dexter and one another in sinister. The eye has the other structures. We found the thick eye sheath on and under the eye. If see more deeply to the eye, there is smooth membrane called membrane nictitan or sleep membrane. The function is to safe the eye when the frog is swimming or diving in the water. Between the eyes we can see a pair of nares pore, this is nares anterior. These nares are part of fovea nasalis where the function is for respiratory tools and olfactory tools. The other structure that we also found is membrane tympani. The frog's membrane tympani is outside, the function is detected vibrate or auditory organ.
The dorsal side of frog's trunctus that we observed, show the rough skin, there are many granules in its skin, the function is for respiratory by oxygen diffusion. The other part that we found is dorsalateral dermal plica, it has a pair of plica extending from anterior to posterior. Their limb or extremities divided to two parts, extremities anterior and posterior. The posterior is longer than anterior because of the function. The function is to jump and push it body away when it's swimming. Like a human, the limb separated in to some parts based on their bone. The extremities anterior, composed of brachium, ante-brachium, carpal that has 4 digiti or fingers. In the end of fingers we could find thickening called caws. Whereas, the extremities posterior also separated into 3 parts based to the bon that composed but has different name. The first part named femur, tibia, tarsal that has 5 phalangus or fingers with caws too. Among the phalangus we found smooth web (Karyanto, 2008).
From the morphology that we found, Maskoeri Jasin said in his book Sistematika Hewan (Invertebrata dan Vertebrata), from the morphological characteristics mentioned above, this specimen is a male animal. The specimen that we observed is classifying into species named Bufo Sp. The scientific classification is below:
Kingdom : Animalia
Phylum : Chordate
Sub-Phylum : Vertebrate
Classis : Amphibian
Sub-Classis : Lissamphibian
Order : Anura
Family : Bufoidae
Genus : Bufo
Species : Bufo Sp.
After we observed the morphology, we start to observe the anatomy. The biggest organ inside is hepaticum. Observed organ systems include the digestive system, circulatory system, reproductive system and the respiratory system. Digestive system start from mouth – pharynx – esophagus – gastric – small intestine – large intestine – cloacae (Jasin, 1989). Glandula digestoria that we found is hepaticum, bile and pancrease. The bile shape is like a crystal ball. The hepaticum divided to two parts, sinister and dexter. The sinister one has more lobules than sinister. Beside the hepaticum, we found lung the color is purple pinkish. The organ looks like a group of bubbles.
Bufo Sp. has 4 phase of respiration when it uses its lungs. Those are aspiration, inspiration, expiration phase I and expiration phase II (Artawan, 2010). The aspiration phase is about make the air enter to the mouth cavity or cavum oris. Musculi myhyoideus or musculi mandibularis is relaxation the nares anterior opened then the air can enter to the cavum oris. When the cavum oris's pressure is high, the nares posterior is closed; rima glottidis open, the air enter to the lung from larynx when the M. Mandibulasris is contaction. This phase called inspiration or the air entered to the lungs. After the process diffusion of oxygen and carbon dioxide inside the lungs, the air ready to go to outside. Expiration phase I is outing the air from lung to cavum oris. It happened because the M. Sternohyoideus is contraction, rima glottidis open and the M. Mandibularis is relaxation. After the rima glottidis closed, nares posterior is open, M. Mandibulasris contraction again to outputting the air (Radiopoetro, 1983; Artawan, 2010). The respiration is also happened in the skin, but not all the skin parts. The skin has patch that has pigment where the respiration also hold there (Jasin, 1989).
Bellow the digestive tube, in posterior area, we can find structure colored yellow, from the book, it name is corpus adiposum. The different between male and female is about the structure of oviduct, in amphibian, especially Anura order. Our specimen, from the morphology, we hypotized that the animal is male. From the anatomy organ, we don't find oviduct, and we found structure named testes and the ductus ending in cloacae too. Cloaca is the organ where urogenital and anus is become one ductus and exit by one pore name cloacae pore.
Between the hepar, we can find organ name heart. The amphibians has characteristic, the heart separated to three chamber, one ventricle and two auricles. Bufo Sp. has double closed blood flow, where the blood goes to lung and skin to diffusion air supply then back to heart and the blood goes to all of body to transfer the air supply and other thing contained in blood (Radiopoetro, 1983). In this group of animal, the blood rich of oxygen is mix with blood rich of carbon dioxide, that's why the air transformation not only happened in lung, but also in skin, to decrease contamination of carbon dioxide in high level will be toxin for body (Campbell, 2010).

Refrences
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Artawan, I Ketut. 2010. Bahan Ajar: Zoologi Vertebrata (Presentasi). Singaraja: Universitas Pendidikan Ganesha.
Campbell, Neil A., Jane B. Reece. 2010. Biologi edisi ke 8 jilid II. Translator: Darmaning Tyas Wulandari with original title Biology 8th edition. Jakarta: Penerbit Erlangga.
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Larasati. 2010. Klasifikasi Amphibi (Popular Article). Accessed on webpage http://www.slideshare.net/PutriLarasati1/klasifikasi-amphibi. downloaded date 17th March 2015.
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