Blood

Blood

1. Functions

   • Temperature
   • Temperature regulation
   • Immunity
   • Communication

2. Composition

   • Plasma
     • 55%
   • Red blood cells (erythrocytes)
   • White blood cells (leucocytes)
   • Platelets (thrombocytes)

3. Plasma

   • 55% of blood pale yellow liquid 92% water - 8% solutes antibodies clotting proteins transports materials e.g. glucose, vitamins, salt carries heat serum - without clotting proteins

4. Erythrocytes

   • red blood corpuscles bone marrow biconcave disc shape no nucleus no mitochondria rich in haemoglobin transports oxygen anaemia

5. Leucocytes

   • Defend the body against infection colourless no haemoglobin nucleus mitochondria some are phagocytes e.g. monocytes remove cell debris (some) produce antibodies (some) bone marrow + lymphatic tissue leukaemia
   • Monocytes (macrophages)
     • Engulf pathogens, viruses, cancer cells, and tissues by phagocytosis formed in bone marrow 4-8% of the blood
   • Lymphocytes
     • made in bone marrow and stored n parts of the lymphatic tissue e.g. spleen, lymph nodes, tonsils move using pseudopodia account for 20-25% of white blood cells produce antibodies

6. Platelets (thrombocytes)

   • not cells - no nucleus fragment of large bone marrow cells (megacytes) blood clotting chemicals bone marrow haemophilia

7. ABO blood grouping

   • A
     • A antigens
   • B
     • B antigens
   • AB
     • A and B antigens
   • O
     • no antigens

8. Rhesus factor

   • rhesus antigen - factor D RH + (antigen present) RH - (antigen absent) RH - can be donated to RH + but not the other way around A+/A RH+ A-/A RH-

Images and files in the map