Lab Skill 7: Arthropod

LAB SKILL 7 ARTHROPOD (Crustaceae, Arachnida and Myriapoda) I. Basic theory Characteristic featuresArthropods 1. The segmented body consists of the head (caput), chest (thorax), and stomach (abdomen). 2. Bilaterally symmetrical body shape, triploblastic, protected by an outer skeleton of chitin. 3. Perfect digestive apparatus, the mouth has lateral jaws which are adapted for chewing and sucking. The anus is at the end of the body. 4. The nervous system is a rope ladder. The brain ganglion is connected to the sense organs. 5. Arthropods have sensory organs such as antennae which function as touch tools, single eyes (ocellus) and compound eyes (facet), hearing organs (oninsecta) Andstatocyst(balance tool) in Curstacea. 6. Excretory tools in the form ofcoxalor green glands, ductsMalpighi. 7. Reproductive organs, usually separate. Fertilization is mostly internal (inside the body). A. Crustaceans Crustaceansare aquatic (water) animals found in sea water and fresh water. Characteristic featurescrustaceansare as follows : 1. Body Structure BodyCrustaceanssegmented (segmented) and consists ofcephalothorax(head and chest together) and abdomen (stomach). The anterior (front end) of the body is large and wider, while the posterior (back end) is narrow. On the head there are several mouth organs, namely: a. 2 pairs of antennas b. 1 pair of mandibles, for biting prey c. 1 pair maxilla d. 1 pair of maxillipeds The maxilla and maxilliped function to filter food and deliver food to the mouth. The means of locomotion are legs (one pair eachsegments on the abdomen) and function for swimming, crawling or sticking to the bottom of the water. 2. Organ Systems a. Digestive system FoodCrustaceansin the form of carcasses of small animals and plants. The digestive organ in the form of a mouth is located in the anterior part of the body, meanwhile esophagus, stomach, intestines and anus are located posteriorly. This animal has digestive glands or liver located in the head and chest on both sides of the abdomen. Apart from being excreted from the anus, the remains of digestionare also excreted through excretory organs called green glands which are located in the head. b. Nervous system Nervous systemCrustaceansis a rope ladder. The brain ganglion is connected to the sense organs, namely the antennae (touch organs),statocyst(balance device) and compound eyes (facets) which have stems. c. Bloodstream system Bloodstream systemCrustaceanscalled open blood circulation. This means that blood circulates without going through blood vessels. Blood does not contain hemoglobin, but rather hemocyanin, which binds O2(oxygen) low. d. Respiratory system In generalCrustaceansbreathe with gills. ExceptCrustaceansthose of very small stature breathe with the entire surface of their body. e. Reproductive Equipment The reproductive organs are generally separate, except in a few Crustaceans low. The female genitals are found on the third pair of legs. Meanwhile, the male genitals are found on the fifth pair of legs. Fertilization occurs externally (outside the body).During their growth, shrimp experience ecdysis or change of skin. Adult shrimp experience ecdysis twice a year, while young shrimp experience ecdysis once every two weeks. Apart from that, shrimp are capable of autotomy (severing part of their body parts). For example:The shrimp will break off part of the base of the leg, if we catch the shrimp by the leg. Then the leg will grow back through a regeneration process. 3. ClassificationmCrustaceans Based on body sizeCrustaceansgrouped as follows: a.Entomostraca(lower shrimp) of the Entomostraca group generally constitute zooplankton, float in the water and are fish food. The division of orders included Entomostracainclude: 1)Branchiopods Example: Daphnia pulex And Asellus aquaticus. This animal is often called a water flea and is one of the constituents of zooplankton. Breeding takes place automaticallyparthenogenesis. 2)Ostracoda Example:Cypris candida,Codona fertile. Lives in fresh water and sea as plankton, small body and can move with antennae. 3)Copepods Example:Argulus indicus, Cyclops. Lives in sea water and fresh water, and is a plankton and parasite, its body segmentation is clear. 4)Cirripedia Example: Take off orBernacle,Sacculina. The body with head and thorax is covered with a disc-shaped carapace and lives in the sea attached to rocks or other objects.Cirripediasome are parasitic. Way of life Cirripediavarious. One of them is the Bernacle which is found at the bottom of ships, boats and poles that are fixed in the sea or floating in the sea. b.Malakostraca(higher shrimp), this animal lives mostly in the sea, some live in fresh water. Its body consists ofcephalothorax namely the head and chest together and the stomach (abdomen). Malakostraca is divided into 3 orders, namelyIsopods, StomatopodsAndDecapoda. 1)Isopods flat body,dorsiventral, same-legged. Example:Onicus asellus(boat flea) andLimnoria lignorum,both are wood scrapers. 2)Stomatopods Example:Squilla empusa(mantis shrimp). Living in the sea, its body shape resembles a praying mantis and has striking colors. The back of the head has a carapace. The head is equipped with two movable anterior segments, the eyes and the antennae. 3)Decapoda(ten foot) Included in this order are shrimp and crab. This animal has ten legs and is a group of shrimp whose role is very important for human life. Decapoda is widely used as a food source rich in protein. Examples are shrimp, crab, crab and crab. Head and chest become onecephalothorax) which is covered by a carapace. The body has 5 pairs of legs or ten legs so it is also called a ten-legged animal. Live in fresh water, and some live in the sea. Some examples of Decapoda below are descriptions, namely: a) Shrimp -Penacus setiferus(tiger prawns), live in brackish water, are delicious to eat and are widely cultivated. -Macrobrachium rasenbengi(shrimp), delicious to eat, lives in fresh and brackish water. -Cambarus virilis(freshwater shrimp) -Panulirus versicolor (crayfish), live in sea water and do not have scalpels. -Palaemon carcinus(cuttlefish shrimp) b) Crab -Portunus sexdentatus(crab) -Neptune peligicus(crab) /Pagurus sp. -Parathelpusa maculata(crab) -Scylla serrata(crab) -Birgus latro(canary crab) B. Arachnids MemberArachnidsincluding scorpions, spiders, mites or ticks. Most of these animals are parasites that harm humans, animals and plants.Arachnidsis both carnivorous and predatory. The place of life is on land. Characteristic featuresArachnids 1. The body is divided into head-chest (cephalothorax) and clearly distinguishable abdomen, exceptAcarina. 2. On the head and thorax there are no antennas, but have several pairs of single eyes, mouth,keliseraAndpedipalps. 3. Has 4 pairs of legs on the head and chest. 4. The excretory apparatus is equipped with channelsmalpighiand glandscoxal. 5. Respiratory apparatus in the form oftrachea, book lungs or book gills 6. Male and female genitals are separated, the genital opening is open in the anterior part of the abdomen, fertilization is internal (inside). 7. The ladder nervous system with the dorsal ganglion (brain) and the ventral nerve cord with pairs of ganglia. 8. The mouthparts and digestive organs of food are mainly adapted for sucking and have poison glands 9. Habitat (place to live) on land, in general but there are also parasites. Those included in the order Arachnida are: a.Scorpionida Example: Scorpion (Vejovis sp, Hadrurus sp, Centrurus sp) and Ketonggeng (Buthus). This animal has a multi-segmented stomach and the last segment turns into a means of self-defense. b.Arachnoid Examples are all kinds of spiders, including:Dome web spider (found in Botswana, South Africa), Primitive spiderLiphistius(in the jungles of Southeast Asia), Trapping spider (in Malaysia), Hunter spider (in Mexico), Wolf spider, Poisonous spider Latrodectes natansAndLaxosceles reclusaand Tarantulas (Rhechostica hentz) C. Aracina The characteristic characteristic of this animal's body is that it has no books, generally parasites on birds and mammals, including humans.Aracina useful for controlling insect populations, especially insect pests. However, many of these animals also cause a lot of harm to humans, especially animalsAracinafor example: 1.Tickscauses itching or scabies in humans 2.Psoroptes equicauses scabies in sheep, rabbits, horses. 3.Ododectes cynotis(ear scabies mite) attacks dogs and cats. D. Myriapoda Myriapoda comes from the wordmyria: many andpodos: legs, so they are called multi-legged animals 1. Chilopods This is a type of centipede that has legs on each segment of its body. The characteristics are: a. Can move quickly and are carnivorous. b. The head is equipped with a pair of antennas. c. The body is flat from the front to the back d. The first pair of legs is modified to poison prey. Example: Scolopendra sp, Scutigera sp 2. Diplopoda It is an animal with many legs, its movements are slower than centipedes. The characteristics are: a. There is a pair of legs on each body segment b. The first 4 segments only have one pair of legs c. The body shape is cylindrical d. The head is well divided and has a pair of antennae. e. Example: Keluwing(Passedsp), Limulus polyphemus (horse shoe) II. Tools and materials Tool : 1. Loope 2. Paraffin tub 3. Ether 4. Straight pin 5. Tweezers 6. Surgical tools 7. Microscope 8. Cavity slide 9. Tissue Material : 1. Giant prawns / tiger prawns 2. Crab/crab 3. Crab/yuyu 4. Spider 5. Centipede, 6. Centipede 7. Centipede 8. Scorpion 9. Daphniasp III. Ways of working 1. Anesthetize the object with ether 2. Place the object on the paraffin bath, observe and observe: body segments, body parts, antennae, and habitat 3. Draw the morphology of each object observed and make a taxonomic classification.