Lab Skill 8 Arthropod 2 (Insecta)

LAB SKILL 8 ARTHROPOD 2(INSECTA) I. Basic theory Insectaoften called insects or hexapods. Hexapod comes from the word hexa meaning 6 (six) and the word podos meaning feet. Heksapoda means a six-legged animals. It is estimated that the number of insects is more than 900,000 species divided into 25 orders. This shows that there is a lot of variation within the classinsectaboth form and nature and habits. Characteristic featuresInsecta, among others: 1. The body can be clearly distinguished between head, chest and abdomen. 2. Head with: One pair of facet (compound) eyes, single eye (ocellus), and one pair of antennae as a touch tool. Mouth apparatus adapted for chewing, sucking, licking and biting. 3. This part of the mouth consists of the back jaw(mandible), front jaw (maxilla), and upper lip (labrum) and lower lip (labium) 4. The feet change shape according to their function, namely: a. feet for digging (earth dog) b. legs for jumping (grasshopper) c. swimming legs (water beetle) d. legs for collecting polle e. walking legs (ground beetle) f. legs for holding (praying mantis) 5. The stomach (abdomen) has eleven (11) segments or only a few segments. In female grasshoppers, the back of the abdomen is presentovipositorwhich serves to lay the eggs. In the first segment there is a hearing organ or membrane tympanum. 6. The digestive system consists of: mouth, esophagus, crop, stomach, intestines, rectum and anus. 7. Rope ladder nervous system. 8. Respiratory system with tracheal system 9. Living place in fresh water and land. 10. Insects generally undergo changes in shape (metamorphosis) from egg to adult B. The Role of Insects in Human Life Like other invertebrate animals,insectaSome are beneficial and some are detrimental, including: 1.Insectaprofitable a.InsectaEspecially butterflies and bees are very helpful to farmers because they can help the pollination process of flowers. b.Insectacultivated because it can produce honey. For example: honey bee (Apis mellifera). c. In the industrial sector, butterflies and silkworms make cocoons which can produce silk (example:Bombix mori). d. For food, for example laron, gangsir and bee larvae (tempayak) which can be obtained seasonally. e. It is a very important link in the food chain for life. 2. Severalinsectawhich is detrimental, among others a. Transmits several types of diseases such as mice, cholera and dysentery by flies and cockroaches. b. Damages human cultivated plants, for example: grasshoppers, coconut beetles, caterpillars... c. Causes disease in plants, for example:Nilapervata lugens(planthoppers) cause tungro virus disease, grasshoppers (grasshoppers) which suck the fluid of young rice seeds so that rice plants become puso. d. Parasites in humans (sucking blood), for example: mosquitoes, head lice and bedbugs. e. Damages stored food ingredients (soybean flour) by various Coleoptera, for example: rice beetle. f. Many insects live as parasites on livestock and fish. g. Can damage building materials, for example: wood beetles II. Tools and Materials Tool : 1. Loope 2. Scissors 3. Tweezers 4. Ether/chloroform 5. Straight pin 6. Test tube 7. Petri dish 8. Spirit burner 9. Test tube clamp Material : 1. NaOH 10% 2. Grasshopper 3. Dragonfly 4. Butterfly, 5. Cockroach 6. Ant 7. Mosquito 8. Fly 9. Lice III. Ways of working 1. Kill the grasshoppers using ether/chloroform. 2. Observe the three pairs of grasshopper legs, then describe them complete with information. 3. Using a loupe/magnifying glass, observe and describe thefacet structure of the grasshopper's eyes. 4. Observe the mouth by: a. Cut off the grasshopper's head using scissors right at the neck b. Place the head in a 10% NaOH solution in a test tube c. Insert a pin to prevent shock, d. Heat the NaOH solution, try not to let it overflow, e. When the grasshopper's head has sunk to the bottom of the test tube, stop heating f. Remove then wash the grasshopper's head with water, g. Use a pin (inserted) on the head of the grasshopper, observe with a magnifying glass (loope), h. Match the part with picture (A). i. Observe the last segment of the grasshopper's stomach, then compare it with picture (B)