Blood Tissue and Plasma MCQ 1

Blood Composition

• Blood is a tissue consisting of many cells working together, with functions including transportation of oxygen, waste products, and hormones, as well as heat transport from internal organs to plasma.
• Blood has four main parts: plasma, red blood cells (RBCs), white blood cells (WBCs), and platelets.

Plasma

• Plasma is the yellow liquid part of blood, making up approximately 55% of blood volume.
• Functions of plasma include:
  • Transporting RBCs, WBCs, platelets, and hormones around the body.
  • Transporting heat around the body.
  • Acting as an excellent solvent, mainly composed of water (approximately 92%).

Red Blood Cells (RBCs)

• Produced in red bone marrow.
• Lacking a nucleus, RBCs are unique in this characteristic.
• Functions:
  • Transporting oxygen around the body.
• Adaptations for oxygen transport:
  • Biconcave shape for maximum surface area.
  • Containing iron pigment hemoglobin to carry oxygen.
  • Flexibility to prevent damage.

White Blood Cells (WBCs)

• Produced in bone marrow.
• Lacking a definite shape, WBCs change shape to fit through narrow spaces.
• Functions:
  • Fighting infection.
• Two main types of WBCs:
  • Lymphocytes: primarily active in the lymphatic system, producing antibodies and engulfing pathogens.
  • Monocytes (Macrophages): found throughout the body, engulfing and destroying pathogens.

Platelets

• Produced in bone marrow.
• Function: clotting blood to reduce blood loss and prevent micro-organism entry.
• Importance: Haemophiliacs are unable to form blood clots.

Blood Groups and Rhesus Factor

• Four main blood groups: A, B, AB, and O.
• Importance of matching blood types in transfusions to prevent harm to recipients.
• Rhesus factor: 85% of Irish people have this antigen on their RBCs.