Blood
Learning objectives
After completing this study unit you will be able to:
- Understand the composition of blood.
- Describe the different types of blood cells and their functions.
Watch video
Blood is composed of 45% cells such as erythrocytes, leukocytes and platelets, and 55% blood plasma. Blood plasma consists mainly of water and contains proteins, antibodies, electrolytes and other substances.
Erythrocytes, also known as red blood cells, transport oxygen throughout the body. Leukocytes, or white blood cells, play a role in the immune system, while thrombocytes, also known as platelets, are responsible for blood clotting. Other tasks of the blood are the transport of nutrients, hormones and heat as well as maintaining the acid-base balance.
Watch the following video to learn more about its components and histological appearance:
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Browse atlas
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Ready to review all these structures in further detail? Browse our image gallery below:
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/blood-smear/XyJgj9dDuPmvgi0qlAr7Q_Blood_smear.png "Blood smear (Sanguis); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/erythrocyte/1jmYAWXa8oYVdAFE85dM5Q_Erythrocytes.png "Erythrocyte (Erythrocytus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/erthyrocyte-rouleau/SsIk0ypDykcRV2aWrIJk6g_Erythrocyte_rouleau_magni.png "Erythyrocyte rouleau (Strues erythrocytorum); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/reticulocyte/72hNeau0BiMdcLfJRLnHw_Reticulocyte.png "Reticulocyte (Reticulocytus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/small-lymphocyte/5GunvPU2ENHwySxIHYDJw_O2WTM7twZoM7tDdE3qEgg_Lymphocyte.png "Small lymphocyte (Lymphocytus parvus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/large-lymphocyte/H7drvB8xWxC8wiYhlyyFyg_large_lymphocyte_magni.png "Large lymphocyte (Lymphocytus magnus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/monocyte-3/M51o4sjJ4gAFJrCWuyoOcQ_monocyte_magni.png "Monocyte; Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/azurophilic-granules-of-monocyte/ImHJ1kDh2nVChOQqgOTTw_Azurophilic_granules_of_monocyte.png "Azurophilic granules of monocyte (Granula azurophili monocyticus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/thrombocyte/D5mNqiYQa8RFXGK64Jm6Jw_Thrombocytes.png "Thrombocyte (Thrombocytus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/neutrophil/q4MUlfeRotNqSLlteAB1Ww_Neutrophil.png "Neutrophil (Granulocytus neutrophilus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/multilobed-nucleus-of-neutrophil/oyYqpajdPeuO2GstX1og_Multilobed_nucleus_of_neutrophil.png "Multilobed nucleus of neutrophil (Nucleus multilobatus neutrophili); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/sex-chromatin-of-neutrophil/Ql2eL3GNEmphh0FoVfJA_Neutrophil_sex_chromatin_med_mag_magnis.png "Sex chromatin of neutrophil (Chromatinum sexuale neutrophili); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/neutrophilic-band-cell/6qjJz49CbKJAZrpKNSs2A_Neutrophil_band_cell.png "Neutrophilic band cell (Granulocytus neutrophilus non segmentonuclearis); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/basophil/FWIodaCoAHv0gewxXH4vuA_Basophil.png "Basophil (Granulocytus basophilus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/eosinophil/oZABu14Ge0g5ZEaIcR2xKA_Eosinophil.png "Eosinophil (Granulocytus eosinophilus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/eosinophilic-granules/RXYOi3iKonFJYOdx52DvA_Eosinophilic_granules.png "Eosinophilic granules (Granula eosinophili); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/eosinophilic-band-cell/45gDDnfbfiJ7hkEQwWZhQ_Eosinophilic_band_cell_magni.png "Eosinophilic band cell (Granulocytus eosinophilus non segmentonuclearis); Image:"){kind=logo}
Well done!
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