The blood

• Red blood cells, or erythrocytes, contain hemoglobin, a protein that binds to oxygen and carries it to the body's tissues.
• Platelets, also known as thrombocytes, play a role in clotting and wound healing by forming blood clots at sites of injury.
• White blood cells, or leukocytes, are involved in immune responses and defend against infection and disease.
• The bone marrow is responsible for producing all types of blood cells.
• Blood vessels include arteries, veins, capillaries, and lymphatic vessels.
• The spleen is an organ located under the ribcage on the left side of the abdomen that filters the blood and removes old red blood cells from circulation.
• Arteries carry blood away from the heart, while veins return blood back to the heart.
• Blood is composed of plasma, red blood cells, white blood cells, and platelets.
• The spleen is an organ that filters the blood, removes old red blood cells, stores platelets, and produces lymphocytes.
• The blood is a bit acidic. It's pH is 7.35
• Plasma in the blood is the liquid part of the blood that contains dissolved substances such as vitamins, hormones immoglobulins and proteins
• Red blood cells doesn't have a nucleus, so it can carry more oxygen
• Red blood cells carry oxygen from the lungs to the body cells, and carbon dioxide from the body cells to the lungs
• If we doesn't have enough blood cells we get anemia. (vérszegénység). The causes of not having enough blood cells can be acute bleeding, loss of ferrum or B12, or a genetic defect.
• Leukaemia: a malignant progressive disease in which the bone marrow and other blood-forming organs produce increased numbers of immature or abnormal leucocytes. These suppress the production of normal blood cells, leading to anaemia and other symptoms.
• Blood types are determined by the presence or absence of antigens on the surface of red blood cells. The universal blood-donor is the O-, and the AB blood-type is the universal recipient.
• Rh factor is a protein found on the surface of red blood cells
• During the first pregnancy, the Rh- mother's initial exposure to fetal Rh+ red blood cells is usually not sufficient to activate her Rh-recognizing B cells
• During delivery, the mixing of blood results in the mother's plasma B cells eliminating the fetal Rh+ cells from her bloodstream
• In first pregnancies for Rh-D mediated disease, IgM antibodies do not cross the placental barrier, leading to no effects on the fetus
• In subsequent pregnancies with Rh+ fetuses, IgG memory B cells mount an immune response when re-exposed
• IgG anti-Rh(D) antibodies cross the placenta and enter fetal circulation
• These antibodies are directed against the Rhesus (Rh) factor found on the surface of fetal RBCs
• Antibody-coated RBCs are destroyed by IgG antibodies binding and activating complement pathways
• We have 5 liters of blood.