Phlebotomy, plasma, blood

• What percentage of medical interventions rely on test results from hospital laboratories?

  More than 80%
• What are the main disciplines within Pathology in hospital laboratories?

  • Clinical Biochemistry
  • Haematology
  • Transfusion & Transplantation
  • Clinical Immunology
  • Microbiology
  • Histopathology & Cytopathology
• What is the primary role of Biomedical Scientists in hospital laboratories?

  To carry out tests and deliver accurate, quality assured results
• What is the focus of Clinical Scientists in hospital laboratories?

  Developing new techniques and troubleshooting unusual cases
• What is Phlebotomy?

  • Process of taking blood
  • Usually performed by venepuncture
  • Often uses a needle and vacutainer
• What types of tests can blood be used for?

  Full blood counts, blood grouping, biochemical assays, microbiology, immunology, and oncology
• What is the composition of blood?

  • Cells: RBCs, WBCs, platelets
  • Plasma: Water, ions, plasma proteins
  • Functions: Respiration, transport, protection, repair, thermoregulation
• What is the average volume of blood in a human body?

  4 to 6 liters
• What is the function of plasma proteins in the blood?

  They maintain osmotic pressure and transport substances
• What are the main types of plasma proteins and their functions?

  • Albumin: Maintains osmotic pressure, carries hydrophobic substances
  • Globulins: Immunity, transport, inhibitors
  • Clotting factors: For coagulation
• What happens when there is a drop in plasma proteins?

  It reduces osmotic pressure, resulting in pitting oedema of tissues
• What are the roles of electrolytes in plasma?

  • Osmotic balance
  • Muscle contraction
  • Transmission of nerve impulses
  • Acid-base balance
• What is the normal pH range of plasma?

  Between 7.35 and 7.45
• What are the functions of vitamins in plasma?

  • B complex: Energy release, DNA synthesis
  • C: Collagen formation, antioxidant
  • Folic acid: DNA synthesis, neural tube development
  • A: Vision, cell growth
  • D: Bone calcification
  • E: Antioxidant
  • K: Coagulation factor synthesis
• What are the roles of minerals in plasma?

  • Calcium: Bones, teeth, muscle action
  • Phosphate: Energy, membranes
  • Sodium: Muscle and nerve function
  • Potassium: Muscle and nerve function
  • Iron: RBCs, metabolism
  • Iodine: Thyroid hormones
• What are the waste products of protein metabolism transported in plasma?

  Urea, creatinine, uric acid
• How is oxygen primarily transported in the blood?

  Mostly on hemoglobin
• What are the classes of hormones found in plasma?

  • Protein/peptide hormones: Hydrophilic (e.g., insulin)
  • Steroid hormones: Hydrophobic (e.g., cortisol)
  • Tyrosine derivatives: Either hydrophilic or hydrophobic (e.g., adrenaline)
• What is the normal range for urea in plasma?

  1. 5-6.7 mmol/L
• What is the normal range for sodium in plasma?

  135-145 mmol/L
• What is the normal range for potassium in plasma?

  1. 5-5 mmol/L
• What is the normal range for creatinine in plasma?

  70-110 µmol/L
• What is the normal range for eGFR in plasma?

  Greater than 90
• What are the true/false statements regarding plasma?

  • Electrolytes are the biggest contributor to osmotic pressure: True
  • Liver disease is the primary cause of ascites due to a drop in plasma proteins: True
  • Plasma pH is tightly regulated between 6.35 and 6.45: False (correct range is 7.35-7.45)
  • Urea, creatinine, and uric acid are waste products of respiration: False (they are waste products of protein metabolism)
  • Gases must be carried by a binding protein to travel in the blood: False (oxygen is carried by hemoglobin)
• What is the structure of Red Blood Cells (RBCs)?

  Biconcave discs, flexible, ~7µm in diameter, anucleate
• What is the primary function of Red Blood Cells (RBCs)?

  Transport of oxygen and carbon dioxide around the body
• What are the critical roles of RBCs in the body?

  • Critical role in respiration
  • Transport of gases (oxygen and carbon dioxide)
• What is the function of oxytocin?


  Oxytocin is a hormone involved in various physiological processes.
• What type of hormones are steroid hormones?

  Steroid hormones are hydrophobic and require carrier proteins.
• Give examples of steroid hormones.

  Cortisol, oestrogen, and testosterone are examples of steroid hormones.
• What are tyrosine derivatives?

  Tyrosine derivatives can be either hydrophilic or hydrophobic hormones.
• Provide examples of tyrosine derivatives.


  Adrenaline and thyroxine are examples of tyrosine derivatives.
• What do U&Es stand for in plasma tests?

  U&Es stand for urea and electrolytes.
• What is the normal range for urea in plasma tests?

  The normal range for urea is 2.5-6.7 mmol/L.
• What is the normal range for sodium in plasma tests?

  The normal range for sodium is 135-145 mmol/L.
• What is the normal range for potassium in plasma tests?

  The normal range for potassium is 3.5-5 mmol/L.
• What is the normal range for creatinine in plasma tests?

  The normal range for creatinine is 70-110 µmol/L.
• What does eGFR stand for and what is its normal value?

  eGFR stands for estimated Glomerular Filtration Rate, and its normal value is >90.
• Why are electrolytes important in plasma?

  Electrolytes are the biggest contributors to osmotic pressure, keeping water in the blood vessels.
• What is the primary cause of ascites related to liver disease?

  Ascites is primarily caused by a drop in plasma proteins (albumin) due to liver disease.