Kelenjar Pankreas (Langerhans)

http://www.youtube.com/watch?v=qzjjW--I-2Q&feature=player_embedded

gambar anatomi kelenjar pankreas

• Kelenjar pankreas merupakan sekelompok sel yang terletak pada pankreas, sehingga dikenal dengan pulau – pulau langerhans.
  

• Kelenjar pankreas menghasilkan hormon insulin dan glukagon. Insulin mempermudah gerakan glukosa dari darah menuju ke sel – sel tubuh menembus membrane sel.
  

• Di dalam otot glukosa dimetabolisasi dan disimpan dalam bentuk cadangan.
  

• Di sel hati, insulin mempercepat proses pembentukan glikogen (glikogenesis) dan pembentukan lemak (lipogenesis).
  

• Kadar glukosa yang tinggi dalam darah merupakan rangsangan untuk mensekresikan insulin. Sebaliknya glukogen bekerja secara berlawanan terhadap insulin.

• Pengaturan kadar gula darah

Peningkatan glukosa darah diatas titik pasang (sekitar 90mg/100ml pada manusia) merangsang pankreas untuk mensekresi insulin, yang memicu sel – sel targetnya untuk mengambil kelebihan glukosa dari darah. Ketika kelebihan itu telah dikeluarkan atau ketika konsentrasi glukosa turun dibawah titik pasang, maka pancreas akan merespons dengan cara mensekresikan glukagon, yang mempengaruhi hati untuk menaikkan kadar glukosa darah.

"OPENING"

I love Biology so I copy this from Wikipedia

Biology (from Greek βιολογία - βίος, bios, "life"; -λογία, -logia, study of) is the science of studying living organisms. Prior to the 19th century, biology came under the general study of all natural objects called natural history.

The term biology in its modern sense appears to have been introduced independently by Karl Friedrich Burdach (1800), Gottfried Reinhold Treviranus (Biologie oder Philosophie der lebenden Natur, 1802), and Jean-Baptiste Lamarck (Hydrogéologie, 1802). Biology is now a standard subject of instruction at schools and universities around the world, and over a million papers are published annually in a wide array of biology and medicine journals.

Biology examines the structure, function, growth, origin, evolution, distribution, and classification of all living things. Five unifying principles form the fundamental axioms of modern biology: cell theory, evolution, gene theory, energy, and homeostasis.

These fields are further divided based on the scale at which organisms are studied and the methods used to study them: biochemistry examines the fundamental chemistry of life; molecular biology studies the complex interactions of systems of biological molecules; cellular biology examines the basic building block of all life, the cell; physiology examines the physical and chemical functions of the tissues and organ systems of an organism; and ecology examines how various organisms interrelate with their environment.