Carolus Linnaeus

Carolus Linnaeus, 1707-1778, is a Swedish physician. He had interest in studying plants. He observed and noted the characteristics of different types of plants he found. Based on the similarities and differences in the plants, he made classification. Linnaeus published Species Plantarum in the dsitinguished Systema Naturae that includes organism classification. Because of this works, he is known as the founding father of classification (taxonomy)

Symbols in Laboratory

Pelajaran yang saya peroleh hari ini adalah tentang simbol-simbol yang sering kita jumpai di ruang laboratorium, kemanan tu penting yang nggak friend....Nah agar saat kita berada di ruang laboratorium nggak celulak celuluk (kaya kebo getu) ada baiknya teman2 tau apa makna dari lambang2 tersebut, wokey....

radioactive

yang ini simbol bahaya radioaktif, kayak uranium getu....

flammable

yang ini namanya flammable artinya mudah terbakar

                                       

kalo yang ini kita semua nggak boleh melakukannya, baik sekedar mencoba atau buat gagah2an....ruang lab bisa pengap....hehehehe...yang ini nggak cuma di lab, di pom bensin dan ruang pak kepsek juga ada kok...

Rachel Carson

After the World War II, many types of new insecticides came to the market, including DDT, which is worshipped as the main weapon in the war to combat pest and to increase harvests. Nobody considered the effect that insecticides may cause, which cannot be decompossed naturall by the soil and other organisms. In 1962, a book written by an American marine biologist, Rachel Carson (1907-1964), entitled Silent Spring attracted many people on the destructions caused by these chemicals. In her book, Carson presented an evidence that insecticides do not kill the pest only. The secondary consumers predate insect that are infected by the chemical sprays and therefore this accumulates pesticides in the bodies of the secondary consumers. The chemicals accumulate more in every increasing rank of thropic pyramid so the danger seriously threats the organism in the top of food web, including human beings. Carson wants that not only time will come when the song of birds are not heard anymore to welcome the spring, but the human beings have also threatened their own exixtence.

Hazardous Chemical Substances

Hazardous chemical substances include

• Poisonous Chemicals

 For example : alcohol, metahnol, carbon monoxida and chloride acid

• Explosive Chemicals

For example : strong acid (chloride acid and concentrated sulfate acid) must be poured into Erlenmeyer containing water slowly using a rod stirrer

• Coorosive and Irritative Chemicals

Corrosive substances stimulate rust on metals. Irritative substance causes irritation on exposed body tissue. Example of  corrosive and irrittative chemical include sulfate acid, chloride acid, nitrate acid and formaldehyde

• Vaporable and Flammable Chemicals

For example : alcohol, methanol, eter and acetone

• Carcinogenic Chemicals

Carcinogenic Chemical are chemical substances that promote the development of cancer cells. For example, food coloring or a lipstick that contains rodamine B, benzene, nitrosophenol or cigarette smoke.

• Radioactive Chemicals

Radioactive chemicals are often used in medicine, agriculture and also BATAN (National Atomic Energy Agency). For  example : X-ray, laser and uranium.

Thermometers

A thermometer is an instrument to measure temperature. A thermometer contains either hydrargyrum or alcohol that function to indicate the low or high level of temperature. A thermometer has different types depending on the purpose of its use. For instance, maximum-minimum thermometer is used to measure air temperature, laboratory thermometer is used in laboratory research and clinical thermometer is used to measure body temperature.

Antonie Van Leeuweenhoek

Born in Delft, Holland by the end of XVII century could succesfully invent a simple microscope following his dilligent and careful works. He could see tiny  weird thing in a drop of water that he took from container of soaked straw under his microscope. Leeuwenhook is popularly known as the father of microbiologi.