BODY FLUIDS

Cairan tubuh menempati +/- 60 % BB tubuh : Wanita dewasa muda : 50 - 55% Berat Badan Pria dewasa muda : 55 - 60% Berat Badan Bayi : 75% Berat Badan Usia lanjut : 45% Berat Badan

Total Cairan Tubuh 67 % 33 % Cairan Intraseluler Cairan Ekstraselular 75 % Cairan Intertisial 25 % Cairan Intravascular

What is Blood Brain Barrier? The BBB is formed by the single layer of endothelial cells that line the inner surfaces of capillaries in the brain. It is a semi-permeable capillary membrane; that is, it allows some materials to cross, but prevents others from crossing. In most parts of the body the capillaries, are lined with endothelial cells. The endothelial tissue has small spaces between each individual cell so substances can move readily between the inside and the outside of the vessel. However, in the brain, the endothelial cells fit tightly together and substances cannot pass out of the bloodstream. (Some molecules, such as glucose, are transported out of the blood by special methods such as active transport.)

Functions and Properties of the BBB The BBB has several important functions: Protects the brain from "foreign substances" in the blood that may injure the brain. Maintains a constant environment for the brain. General Properties of the BBB Large molecules do not pass through the BBB easily. However, lipid soluble molecules rapidly cross the BBB into the brain. Molecules that have a high electrical charge to them are slowed. Therefore: The BBB is selectively permeable to :Oxygen, Carbon dioxide and glucose The BBB is not permeable to hydrogen ions

CENTRIFUGATION

Eritrosit bersirkulasi selama 120 hari           -  sel darah merah yang rusak difagosit oleh               makrofag dalam limfa, hati dan sumsum tulang              akan terurai menjadi :              - globin : bagian protein yang akan menjadi asam                            amino dan akan diperbaharui dalam                            proses sintesis seluler              - hem    : bagian yang mengandung zat besi                             diubah menjadi biliverdin (pigmen                             hijau) kemudian menjadi bilirubin                             pigmen kuning) yang dilepas ke dalam                            plasma. bilirubin diserap oleh hati dan                            disekresikan ke cairan empedu.

Leukosit A.  AGRANULOSIT  B. GRANULOSIT

Proses Pembekuan Darah Bila terjadi luka, trombosit akan pecah mengeluarkan trombokinase atau tromboplastin. Trombokinase akan mengubah protrombin menjadi  trombin. Trombin mengubah fibrinogen menjadi fibrin yang berbentuk  benang-benang yang menjerat sel darah merah dan membentuk gumpalan  sehingga darah membeku. Protrombin adalah senyawa globulin yang larut dan dihasilkan di hati dengan bantuan vitamin K (perubahan protrombin yang belum aktif menjadi trombin yang aktif dipercepat oleh ion kalsium (Ca). Fibrinogen  adalah protein yang larut dalam plasma darah.

A KIDNEY

NEPHRON

GLOMERULUS

a. Filtration (filtrasi) b. Reabsorption (reabsorpsi) c. Secretion (sekresi) Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

URINE FORMATION

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