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DARAH6 – 8 % berat tubuh totalDarah : suspensi partikel (sel-sel darah) dalam larutan koloid cair yg mengandung elektrolit yaitu PLASMA

Komponen cair : PLASMA 90% air sebagai medium TRANSPOR

10 % Zat terlarut : Protein : albumin, globulin, fibrinogen Elektrolit misal Na , K , Fosfor Gas terlarut Produk sisa metabolisme misal : Nitrogen non-

protein , urea , asam urat

Zat-zat gizi : gula, asam amino, lemak, kolesterol, Vitamin

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Suplai O2 ke jaringanSuplai nutrien : glukosa, asam amino, asam lemak

( terlarut dalam darah atau terikat protein plasma )Membuang sampah metabolik : CO2, urea, asam laktatImunologi/ kekebalan tubuh seluler & humoral (antibodi)Koagulasi / pembekuan darah menutup lukaMedia transport substansi penting misal hormon ,

petanda kerusakan jaringanMengatur keseimbangan asam basa / pH tubuh( pH normal 7,35 – 7,45 )Mengatur suhu tubuh

Fungsi Darah

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ALBUMIN

Protein plasma paling banyak

Diproduksi di Hepar

Fungsi : Mempertahankan volume darah , pH Keseimbangan elektrolit Mengikat berbagai zat yg sulit larut

TRANSPORTASI Misal :Bilirubin, garam empedu, hormon Tiroid, Kolesterol, Obat-obatan ( misal antibiotika )

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GLOBULINDiproduksi di Hepar3 Subkelas : Globulin alfa , beta , gama

Fungsi : • Mengikat dan mengangkut zat dalam plasma Misal : Besi , Hormon Tiroid, Kolesterol• Globulin Gama : Imunoglobulin Antibodi Untuk mekanisme pertahanan tubuh• Pembekuan darah

FIBRINOGEN4% dari protein serumFungsi : pembekuan darah

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DARAH

SEL

EritrositLekositTrombosit

CAIRAN

Plasma (dengan antikoagulan)Serum

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Sel-sel darah : 45 – 60% volume darah total terutama : Eritrosit Lekosit & trombosit walaupun secara fungsional sangat esensial tetapi merupakan sebagian kecil darah.

• Proporsi SEL dan PLASMA dijaga relatif KONSTAN

• Sel-sel darah mempunyai UMUR terbatas perlu PEMBENTUKAN optimal yang konstan mempertahankan jumlah yg diperlukan memenuhi kebutuhan jaringan

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HEMATOLOGI Ilmu tentang darah & jaringan pembentuk darah Mempelajari :

Struktur, fungsi, komponen seluler darah, volume darah

Hubungan fisik antara sel2 darah dengan plasma

Komponen plasma yg berkaitan dg sifat & fungsi darah misal “ protein faktor-faktor koagulasi “

Perubahan salah satu komponen atau fungsi Penyakit Hematologi.Perubahan hematologi manifestasi penyakit lainH

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Proses pembentukan & pematangan sel darah disebut HEMATOPOIESIS

Terjadi dalam sumsum tulang vertebra, tulang tengkorak, pelvis, sternum ,iga, epifisis proksimal tulang panjang

Bila kebutuhan meningkat misal perdarahan , penghancuran sel berlebihan ( HEMOLISIS) pembentukan sel darah timbulm lagi dalam seluruh TULANG PANJANG seperti pada anak-anak.

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HEMATOPOESIS

HEMATOPOESISrangkaian proses produksi dan perkembangan sel darah

mulai dari STEM SEL (sel induk) HEMOPOETIKsampai beredar di darah tepi

TEORI PEMBENTUKAN SEL DARAHMonophyletik (uniphyletik) : Maximon dkk, 1948 Semua sel darah berasal dari 1 sel induk

Poliphyletik : Sobin dkk, 1936Masing sel darah mempunyai STEM SELsendiri, terpisah denganyang lain

Monophyletik & Poliphyletik ( Intermediate )

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HEMATOPOESIS

REGULASI

Agar supaya jumlah sel darah tetap , maka stem cell mengadakan regulasi dengan cara :- proliferasi- diferensiasi

FAKTOR YG MEREGULASI PEMBENTUKAN SEL DARAH

.Eritropoetin : Untuk pembentukan eritrosit Lekopoetin : Untuk pembentukan lekosit Trombopoetin : Untuk pembentukan trombosit

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HEMATOPOESIS

TEMPAT PEMBENTUK AN SEL DAR AH

Pada Embryo dan Foetus :

Stadium MESOBLASTIK : minggu ke 3-6 kehamilan Oleh sel mesenkim di YOLK SACCEritrosit inti besar & umur pendek : megaloblasProduksi pada Minggu ke-6 menurun diganti organ lain

Stadium HEPATIK : minggu ke-6 s/d bulan ke 5-9 kehamilanTerdiri dari organ lien, hepar, limfonodi

Stadium MIELOID : bulan ke- 6 s/d lahirPembentukan di SUMSUM TULANG :Eritrosit, lekosit, megakariosit.

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HEMATOPOESIS

TEMPAT PEMBENTUK AN SEL -SEL D AR AHSetelah lahir s/d dewasa :1 Hemopoesis MEDULER : lahir s/ d 20 tahun

Setelah 20 tahun korpus tulang panjang berangsur diganti lemak, karena produksinya berkurang

Pada dewasa sumsum tulang merah : tulang panjang, tulang pendek, tulang pipih

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HEMATOPOESIS

2 Hemopoesis EKSTRAMEDULERPada keadaan abnormalmisal pada keganasan darah LeukemiaOrgan : lien, hepar, limfonodiGranulosit dan megakariosit

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ERITROPOESIS

Perkembangan sel darah merah 1. Mitosis (pembelahan) 2. Maturasi (pematangan) 3. Pelepasan (dari sumsum tulang ke aliran darah)

Ciri Perkembangan sel darah merah1. Ukuran sel2. Warna sitoplasma3. Inti sel4. Nukleoli5. Benang kromatin inti

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ERITROSIT

Selama hidupnya berada di sirkulasiBentuk : cakram bikonkaf , diameter 8 micron

FLEKSIBEL membran lentur , deformasi kapiler

Masa hidup : 120 hari

Fungsi utama : membawa O2 dlm darah arteri sistemik ke jaringan dan mengembalikan CO2 dalam darah vena ke paru

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Masa janin : eritrosit diproduksi Yolk SAC hati dan limpa sumsum tulang

Dewasa : Sumsum merah di : - Sternum , Iga - Panggul - Tengkorak - Bagian Proksimal tulang paha dan lengan

Sel bakal / Stem cell PLURIPOTENSIAL terus menerus membelah diri ber DIFERENSIASI menjadi berbagai jenis sel darah

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ERITROSIT

Eritrosit mengandung protein khusus yg terikat besi yaitu Hemoglobin mengangkut gas2 respirasi ( O2 dan CO2) secara selective-binding dan meningkatkan kelarutan gas2 tersebut dalam darah.

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ERITROSIT

Hemoglobin : Hem ( besi) + Globin ( protein )Hb : mengangkut O2 dan CO2, pH darah / Buffer darah

Hb yg dominan pada dewasa setelah usia 3-6 bulan : HbA dalam jumlah sedikkit : HbF , HbA2

Eritrosit tidak dapat membelah diri eritrosit tua di sirkulasi dihancurkan di LIMPA diganti sel baru oleh sumsum tulang (ERITROPOIESIS)

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Komponen HEM : Besi

Sumber Besi :

Diet / Makanan : sebagian kecil 10% besi dalam diet yg diabsorbsi dipermudah Vit C

Cadangan besi di jaringan RES ( Retikuloendotelial ) berasal dari penghancuran Eritrosit tua “ daur ulang besi “

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GLOBIN

Susunan asam amino dalam Globin menentukan STRUKTUR & FUNGSI Hb

PEMATANGAN SEL (inti & sitoplasma eritrosit) : - Vit B12 : makanan hewani- Asam Folat : sayuran

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PEMECAHAN ERITROSIT

Eritrosit pada akhir masa hidupnya mengeluarkan Hb ke sirkulasi darah Hb diuraikan di Hepar dan Lien :

molekul GLOBIN diubah menjadi Asam amino digunakan lagi oleh tubuh

Besi / Hem Hepar dan Lien Bilirubin empedu

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Kontrol / Regulator Eritropoiesis : Hormon ERITROPOIETIN di Ginjal merangsang Eritropoiesis di sumsum tulang

Bila kebutuhan eritrosit meningkat (misal perdarahan) sumsum tulang mengeluarkan eritrosit imatur : RETIKULOSIT

Petanda peningkatan aktivitas Eritropoiesis : pemeriksaan darah Retikulosit

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LEKOSITDibentuk di sumsum tulang dari Stem cellSetelah dibentuk Lekosit diangkut dalam darah menuju berbagai jaringan melakukan tugas fisiologiknya

Jenis : Bergranula : GRANULOSIT POLIMORFONUKLEAR Eosinofil, Basofil, Neutrofil Nukleus tersegmentasi menjadi beberapa lobus Sitoplasma mengandung banyak Granula

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LEKOSIT

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Tidak bergranula : AGRANULOSIT MONONUKLEAR Limfosit B dan T, Monosit, Makrofag Nukleus besar, tidak bersegmen Monosit lebih besar dari Limfosit

Gambar Lekosit PMN dan MN

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Lekosit melaksanakan fungsinya diluar darah yaitu :dalam JARINGAN Dapat bergerak / mobile dalam sistem pertahanan tubuh

Lekosit bergerak ke tempat invasi atau jaringan rusak

Peran Lekosit untuk pertahanan tubuhFUNGSI Lekosit :

FAGOSITOSIS PATOGEN ( bakteri, virus) Mengenali & melawan mikroorganisme pada reaksi imun Membersihkan “sampah tubuh”

memfagosit sel-sel mati atau cedera Penyembuhan luka , perbaikan jaringan

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IMUNITAS

Kemampuan tubuh untuk menahan atau mengeliminasi sel abnormal atau benda asing yang berpotensi merusak

Beberapa jenis Lekosit diproduksi dengan berbagai kecepatan Tergantung jenis dan luas serangan

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Maturasi LekositMaturasi Lekosit

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LEKOSIT :Tidak mempunyai Hb tidak berwarna( dicat dg pewarnaan khusus mikroskop )

Bervariasi dalam struktur, fungsi, jumlahUkuran lebih besar dari Eritrosit

5 jenis yg bersirkulasi : Neutrofil Eosinofil Basofil struktur dan fungsi KHAS Monosit Limfosit

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LIMFOSIT berada di JARINGAN LIMFOID : Kelenjar limfe dan Tonsil

Jumlah Lekosit lebih sedikit dari Eritrosit karena hanya mampir sementara dalam darah

Normal :2/3 lekosit sirkulasi : Granulosit terutama Neutrofil1/3 : Agranulosit terutama Limfosit

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NEUTROFIL Spesialis fagositik Sel pertahanan terutama terhadap invasi BAKTERI Penting dalam respons peradangan

Pembersihan DEBRIS

NEUTROFILIA infeksi bakteri akut

Hitung jenis/ hitung diferensial lekosit : proporsi setiap jenis lekosit yang ada.

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EOSINOFIL

Mengandung Granula azurofilik

EOSINOFILIA : peningkatan eosinofil dalam darahEosinofilia dijumpai pada : Alergi misal asma Infeksi parasit internal misal cacing eosinofil melekat ke cacing mengeluarkan bahan2 yg mematikan cacing

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BASOFIL

Jenis lekosit yg paling sedikit jumlahnya Granula menghasilkan HISTAMIN reaksi Alergi HEPARIN

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MONOSIT

Agranulosit Mononuklear

FAGOSIT

Monosit dari sumsum tulang sirkulasi darah menetap di jaringan tubuh Fagosit jaringan yaitu MAKROFAG

Sel Fagositik hanya dapat memakan benda asing dalam jumlah terbatas lalu mati.

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LIMFOSIT

LIMFOSIT BMenghasilkan Antibodi yg beredar dalam darah

LIMFOSIT TTidak menghasilkan antibodiLangsung menghancurkan sel sasaran spesifik yaitu sel-sel tubuh yg telah dimasuki Virus atau Sel kanker disebut “ Respon imun yg diperantarai sel “Respon Imun Seluler

Umur Limfosit : 100 – 300 hariLimfosit beredar diantara jaringan Limfoid, Limfe, Darah.

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TROMBOSITBukan merupakan sel Berasal dari sitoplasma TIDAK berintiDibentuk di sumsum tulangSel induk : Megakariosit

Umur : 10 hari Diambil Makrofag jaringan dan Makrofag di Limpa

Lokasi : Sirkulasi dan Limpa/ Lien (1/3)

Peran : Hemostasis dan pembekuan SUMBAT TROMBOSIT menutup luka kecil di kapiler , PD kecil

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TROMBOSIT

Mencegah tubuh kehilangan darah akibat perdarahan Melakukan fungsinya pada DINDING PEMBULUH DARAH. Pembekuan darah

PROTEIN PLASMA

Pengangkut utama zat gizi & hasil metabolik ke organ tujuan untuk penyimpanan atau ekskresi. Pencegahan perdarahan melalui proses koagulasi

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ANEMIAPengurangan kuantitas atau kualitas eritrosit dlm sirkulasiPenyebab :

Gangguan pembentukan eritrosit Kehilangan eritrosit akibat perdarahan Destruksi / Lisis eritrosit berlebihan

Semua sistem organ terlibat MANIFESTASI KLINIK luas Penurunan Viskositas / kekentalan darah Hipoksia Peningkatan beban kerja jantung

KELAINAN DARAH

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GEJALA KLINIS ANEMIA

PUCAT Konjungtiva, kuku, telapak tangan, mukosa mulut Vasokonstriksi meningkatkan pengiriman O2

DISPNEA , cepat lelah saat aktivitas Pusing, TINITUS oksigenasi SSP

TAKIKARDIA, bising jantung ok peningkatan aliran darah Anemia berat Payah jantung kongestif

ANOREKSIA , NAUSEA, STOMATITIS

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JENIS ANEMIA

ANEMIA AKIBAT KEHILANGAN DARAH Perdarahan akut Perdarahan kronik : Hemoroid, Menstruasi, Keganasan

ANEMIA APLASTIK Sumsum tulang tidak berfungsi pembentukan sel-sel darah menurun Penyebab: Radiasi, Obat, Benzen, Infeksi virus (Hepatitis)

PANSITOPENIA Kekurangan Eritrosit, Lekosit, Trombosit

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ANEMIA HEMOLITIK HEMOLISIS: penghancuran Eritrosit di sirkulasi

Penyakit KETURUNAN / HERIDITER Misal : Talasemia, Hb abnormal

Eritrosit rapuh, mudah robek melewati kapiler, lien Masa hidup Eritrosit PENDEK

MALARIA Parasit Plasmodium masuk Eritrosit hemolisis

Luka bakar / COMBUSTIO berat kapiler pecah hemolisis Reaksi Transfusi

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ANEMIA DEFISIENSI BESIPenurunan sintesis HbPenyebab utama Anemia di dunia

Wanita usia subur, mensturasi, hamil

Penyebab : Asupan besi kurang Bayi pola makan salah, diet hanya sayuran

Absorbsi besi terganggu Terjadi di Duodenum dan Jejunum proksimal

Kehilangan darah kronik : perdarahan saluran cerna, obat Aspirin, Gastritis, Hemoroid

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ANEMIA MEGALOBLASTIKDefisiensi Vit B12 dan asam folat

Penyebab : Asupan / malnutrisi Malabsorbsi , orang tua Infeksi parasit cacing pita makan ikan mentah terinfeksi cacing pita berkompetisi mendapatkan Vit B12 Pecandu allkohol Hamil fetus & laktasi Cara penyiapan makanan yang BENAR ! Masak banyak air Asam folat hilang >>>

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POLISITEMIAKelebihan semua jenis sel darah umumnya volume sel darah merah peningkatan kekentalan (VISKOSITAS) darah

Penyebab : Dehidrasi : demam, luka bakar, muntah, obat Diuretik Merokok CO meningkatkan eritrositosis Tempat tinggal dataran tinggi O2 atmosfir <<< Penyakit jantung

Konsentrasi O2 <<< merangsang Eritropoietin ginjal merangsang Eritropoiesis di sumsum tulang produksi

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KELAINAN SEL DARAH PUTIHLEUKOSITOSIS Peningkatan jumlah Lekosit di sirkulasiDijumpai pada :

Infeksi / peradangan Keganasan, gangguan sumsum tulang

LEUKOPENIAPenurunan jumlah Lekosit di sirkulasi Mudah terkena infeksi !!Penyebab :

Radiasi kerusakan sumsum tulang Invasi bakteri Obat ( misal Antibiotik, Analgetik ) Bahan kimia ( misal Benzene )

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PEMBENTUKAN NANAH

Netrofil dan Makrofag menelan bakter dan jaringan nekrotik mati beberapa hari jaringan meradang rongga mengandung jaringan nekrotik, Netrofil mati, makrofag mati, cairan jaringan disebut NANAH

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LEUKEMIAPenyakit neoplasma yang ditandai proliferasi abnormal sel-sel hematopoietik proliferasi sel darah putih tidak terkontrolPenyebab :

Predisposisi Genetik + Mutan Radiasi Obat sumsum tulang Bahan dari lingkungan

Klinis : Anemia Infeksi Perdarahan Organomegali

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KELAINAN PEMBEKUAN DARAH

TROMBOSITOPENIA Penurunan jumlah trombosit di sirkulasi Mudah mengalami perdarahan Fungsi trombosit : menutup kebocoran kecil di kapiler Perdarahan berasal dari kapiler kecil bintik-bintik perdarahan di jaringan tubuh

HEMOFILI Kecenderungan perdarahan Penyakit koagulasi HERIDITER (kromososm X) Terutama Pria Defisiensi Faktor Pembekuan (Faktor VIII dan IX) Perdarahan sendi sendi nyeri

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Maturasi Eritrosit

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Supply of oxygen to tissues (bound to hemoglobin which is carried in red cells)

Supply of nutrients such as glucose, amino acids and fatty acids (dissolved in the blood or bound to plasma proteins)

Removal of waste such as carbon dioxide, urea and lactic acid Immunological functions, including circulation of white cells, and detection of

foreign material by antibodies Coagulation, which is one part of the body's self-repair mechanism

Messenger functions, including the transport of hormones and the signalling of tissue damage

Regulation of body pH (the normal pH of blood is in the range of 7.35 - 7.45) Regulation of core body temperature

Hydraulic functions

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Blood, a specialized bodily fluid (technically a tissue), is blood plasma (also called plasma), a liquid, in which blood cells are suspended. The blood cells present in blood are red blood cells (also called RBCs or erythrocytes), white blood cells

(includes both leukocytes and lymphocytes) and platelets (also called thrombocytes). Plasma is predominantly water containing dissolved proteins, salts and many other substances, and it makes up about 55% of blood by volume. Blood is a red color,

which is a brighter red when blood is oxygenated.By far the most abundant cells in blood are red blood cells. These contain hemoglobin

, an iron-containing protein, which facilitates transportation of oxygen and carbon dioxide by selectively binding to these respiratory gases and greatly

increasing their solubility in blood. White blood cells help to resist infections, and platelets are important in the clotting of blood.

Blood is circulated around the body through blood vessels by the pumping action of the heart. It is pumped from the strong left ventricle of the heart through arteries to peripheral tissues and returns to the right atrium of the heart through veins. It then enters the right ventricle and is pumped through the pulmonary artery to the lungs

and returns to the left atrium through the pulmonary veins. Blood then enters the left ventricle to be circulated again. Arterial blood carries oxygen from inhaled air to all of the cells of the body, and venous blood carries carbon dioxide, a waste product of

metabolism by cells, to the lungs to be exhaled.Medical terms related to blood often begin with hemo- or hemato- (BE: haemo- and haemato-) from the Greek word "haima" for "blood." Anatomically and histologically,

blood is considered a specialized form of connective tissue, given its origin in the bones and the presence of potential molecular fibers in the form of fibrinogen.

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Blood, a specialized bodily fluid (technically a tissue), is blood plasma (also called plasma), a liquid, in which blood cells are suspended. The blood cells present in blood are red blood cells (also called RBCs or erythrocytes), white blood cells

(includes both leukocytes and lymphocytes) and platelets (also called thrombocytes). Plasma is predominantly water containing dissolved proteins, salts and many other substances, and it makes up about 55% of blood by volume. Blood is a red color,

which is a brighter red when blood is oxygenated.By far the most abundant cells in blood are red blood cells. These contain hemoglobin

, an iron-containing protein, which facilitates transportation of oxygen and carbon dioxide by selectively binding to these respiratory gases and greatly

increasing their solubility in blood. White blood cells help to resist infections, and platelets are important in the clotting of blood.

Blood is circulated around the body through blood vessels by the pumping action of the heart. It is pumped from the strong left ventricle of the heart through arteries to peripheral tissues and returns to the right atrium of the heart through veins. It then enters the right ventricle and is pumped through the pulmonary artery to the lungs

and returns to the left atrium through the pulmonary veins. Blood then enters the left ventricle to be circulated again. Arterial blood carries oxygen from inhaled air to all of the cells of the body, and venous blood carries carbon dioxide, a waste product of

metabolism by cells, to the lungs to be exhaled.Medical terms related to blood often begin with hemo- or hemato- (BE: haemo- and haemato-) from the Greek word "haima" for "blood." Anatomically and histologically,

blood is considered a specialized form of connective tissue, given its origin in the bones and the presence of potential molecular fibers in the form of fibrinogen.

Page 67: Darah

Blood, a specialized bodily fluid (technically a tissue), is blood plasma (also called plasma), a liquid, in which blood cells are suspended. The blood cells present in blood are red blood cells (also called RBCs or erythrocytes), white blood cells

(includes both leukocytes and lymphocytes) and platelets (also called thrombocytes). Plasma is predominantly water containing dissolved proteins, salts and many other substances, and it makes up about 55% of blood by volume. Blood is a red color,

which is a brighter red when blood is oxygenated.By far the most abundant cells in blood are red blood cells. These contain hemoglobin

, an iron-containing protein, which facilitates transportation of oxygen and carbon dioxide by selectively binding to these respiratory gases and greatly

increasing their solubility in blood. White blood cells help to resist infections, and platelets are important in the clotting of blood.

Blood is circulated around the body through blood vessels by the pumping action of the heart. It is pumped from the strong left ventricle of the heart through arteries to peripheral tissues and returns to the right atrium of the heart through veins. It then enters the right ventricle and is pumped through the pulmonary artery to the lungs

and returns to the left atrium through the pulmonary veins. Blood then enters the left ventricle to be circulated again. Arterial blood carries oxygen from inhaled air to all of the cells of the body, and venous blood carries carbon dioxide, a waste product of

metabolism by cells, to the lungs to be exhaled.Medical terms related to blood often begin with hemo- or hemato- (BE: haemo- and haemato-) from the Greek word "haima" for "blood." Anatomically and histologically,

blood is considered a specialized form of connective tissue, given its origin in the bones and the presence of potential molecular fibers in the form of fibrinogen.

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Blood, a specialized bodily fluid (technically a tissue), is blood plasma (also called plasma), a liquid, in which blood cells are suspended. The blood cells present in blood are red blood cells (also called RBCs or erythrocytes), white blood cells

(includes both leukocytes and lymphocytes) and platelets (also called thrombocytes). Plasma is predominantly water containing dissolved proteins, salts and many other substances, and it makes up about 55% of blood by volume. Blood is a red color,

which is a brighter red when blood is oxygenated.By far the most abundant cells in blood are red blood cells. These contain

hemoglobin, an iron-containing protein, which facilitates transportation of oxygen and carbon dioxide by selectively binding to these respiratory gases and greatly

increasing their solubility in blood. White blood cells help to resist infections, and platelets are important in the clotting of blood.

Blood is circulated around the body through blood vessels by the pumping action of the heart. It is pumped from the strong left ventricle of the heart through arteries to peripheral tissues and returns to the right atrium of the heart through veins. It then enters the right ventricle and is pumped through the pulmonary artery to the lungs

and returns to the left atrium through the pulmonary veins. Blood then enters the left ventricle to be circulated again. Arterial blood carries oxygen from inhaled air to all of

the cells of the body, and venous blood carries carbon dioxide, a waste product of metabolism by cells, to the lungs to be exhaled.

Medical terms related to blood often begin with hemo- or hemato- (BE: haemo- and haemato-) from the Greek word "haima" for "blood." Anatomically and histologically,

blood is considered a specialized form of connective tissue, given its origin in the bones and the presence of potential molecular fibers in the form of fibrinogen.