Blood and blood cells

Question 1

What is the function of erythrocytes?

Answer 1

Erythrocytes - transport oxygen and some CO2 between tissues and lungs

Question 2

What are the functions of the different granulocytes?

Answer 2

Granulocytes - Innate resistance to disease

• Neutrophils - Phagocytic, release cytotoxic chemicals from granules, effective against bacteria (most common)
• Eosinophils - Phagocytic, release antihistamines, effective against antigen-antibody complexes
• Basophils - Promotes inflammation (least common)

Question 3

What are the functions of the different agranulocytes?

Answer 3

Agranulocytes - Body defences

• Lymphocytes - primarily specific/adaptive immunity, found in natural killer cells (non-specific direct attack), T cells (specific direct attack) and B cells (release antibodies)
• Monocytes - largest leukocyte, phagocytic, engulfs pathogens and worn out cells, serve as antigen presenting cells

Question 4

What are the functions of platelets?

Answer 4

Haemostasis (reduce blood loss)

Release growth factors for repair and healing of tissue

Question 5

What are the general functions of blood?

Answer 5

Transport
Heat distribution
Immunity
Haemostasis
Homeostasis

Question 6

What is the basic structure of haemoglobin?

Answer 6

4 subunits

each subunit consists of a polypeptide with a haem group containing Fe2+ where O2 binds

Question 7

What is the role of haemoglobin?

Answer 7

Bind O2 co-operatively to form oxyhaemoglobin

CO2 binds with greater affinity to form carboxyhaemoglobin

Question 8

Define anemia and its subclasses

Answer 8

Low blood Hb concentration
Microcytic - small MCV - failure of Hb synthesis due to slow, gradual blood loss e.g. menstruation
Normocytic - normal MCV - acute blood loss due to large no. of RBC lost rapidly
Macrocytic - large MCV - Failure of Hb synthesis due ot fewer but larger RBC e.g. due to pregnancy