PHYSIOLOGY OF HEMOPOIESIS

Question 1

WHY DO WE NEED BLOOD CELLS?

Answer 1

1. RBCs CARRY O2 TO TISSUES AND CO2 TO LUNGS
2. PLTS ARE IMPORTANT FOR BLOOD CLOTTING
3. WBCs IS NEEDED FOR FIGHT INFX

Question 2

SITE OF NORMAL HAEMOPOIESIS IN CHILDREN.

Answer 2

• IN CHILDREN, HAEMOPOIESIS CAN OCCUR IN ALL BONE MARROW OF THE ACTIVE BONES
• AS FOR EXAMPLE:
  1. CLAVICLE
  2. FEMUR
  3. HUMERUS
  4. VERTEBRAE BODIES
  5. SMALL BONES IN HAND AND FEETS

Question 3

SITE OF NORMAL HAEMOPOIESIS IN ADULTS.

Answer 3

• IN ADULTS, THE HAEMOPOIESIS CANNOT OCCUR IN ALL BONE MARROW.
• THIS IS BECAUSE, AS WE AGED, THE BONES BECOME INACTIVE.
• THEREBY NOT ALL LONG BONES CAN UNDERGOES HAEMOPOIESIS.
• IN ADULT, BONES THAT CAN UNDERGOES HAEMOPOIESIS IS
  1. PROXIMAL END OF FEMUR
  2. PROXIMAL END OF HUMERUS
  3. CENTRAL SKELETON

Question 4

WHAT IS EXTRAMEDULLARY HAEMOPOIESIS?

Answer 4

EXTRAMEDULLARY HAEMOPOIESIS IS:
- HAEMOPOIESIS THAT OCCUR OUTSIDE FROM THE MEDULARRY SPACES OF BM.
- IT CAN BE OBSERVED IN HEPATOMEGALY, SPLEENOMEGALY AND HEMOGLOBINOPATHY.
- APPEARANCE INCLUDE ACCELERATED ERYTHROPOIESIS AND HEMATOPOIESIS (FRONTAL BOSSING OF THE SKULL) HAIR ON END PREGNANCY ON SKULL RADIOGRAPH.

Question 5

BRIEFLY DESC REGARDING:
1. MYELOID TISSUES
2. LYMPHOID TISSUES

Answer 5

1. MYELOID TISSUES
   - MYELOID TISSUE IS UNDIFFERENTIATED STEM CELL SPECIFICALLY THE RED BONE MARROW THAT CAN BE FOUND IN MAINLY THE LONG BONE.
   - IT USED TO FORM ALL BLOOD CELL
2. LYMPHOID TISSUES
   - LYMPHOID TISSUE CAN BE SEEN MAINLY IN THYMUS, IN SPLEEN, LYMPH NODE, TONSILS.
   - IT IS USED TO FORM LYMPHOCYTES DERIVED FROM CELLS THAT ORIGINATED IN THE BM.

Question 6

REGULATION OF HEMOPOIESIS NEEDS:

Answer 6

• COLONY STIMULATING FACTOR
• GLYCOPROTEIN HORMONE SUCH AS ERYTHROPOIETIN AND THROMBOPOIETIN.

Question 7

WHAT IS FUNCTION OF COLONY STIMULATING FACTOR?

Answer 7

CSF IS TO:
- SUSTAIN THE FORMATION OF ALL BLOOD CELLS THROUGHOUT LIFE: MAINLY WBC
- IT CAN STIMULATE THE HAEMOPOIESIS

Question 8

WHAT IS THE EXAMPLE OF CSF?

Answer 8

1. MULTIPOTENT CSF
2. GRANULOCYTE CSF
3. GRANULOCYTE- MONOCYTE CSF

Question 9

THE APPEARANCE OF RETICULOCYTES IN PBF INDICATES THAT

Answer 9

THERE IS RAPID PRODUCTION OF RBCS

Question 10

STATE THE FACTORS NECESSARY FOR ERYTHROPOIESIS.

Answer 10

1. EPO
2. THYROXINE
3. HAEMOPOIETIC GROWTH FACTOR (IL AND STEM CELL)
4. VITAMIN B,C,D, AND E

Question 11

BRIEFLY DESC THE FACTORS NECESSARY FOR ERYTHROPOIESIS.

Answer 11

1. EPO
   - ERYTHROPOIETIN IS SECRETED MAINLY BY THE KIDNEY AND SOME BY THE LIVER AND ELSEWHERE.
   - ERYTHROPOIETIN LEVEL WILL BE INCREASES DURING LACK SUPPLY OF O2 SUCH AS DURING HYPOXIA.
   - EPO WILL BIND TO THE PROERYTHROBLAST THEN CAUSING IT TO UNDERGOES CELL DIFFERENTIATION IN WHICH IT WILL BECOME ERYTHROBLAST.
   - ERYTHROBLAST THEN WILL CONTINUE TO UNDERGOES CELL DIVISION AND BECOMING RETICULOCYTES THEN ERYTHROCYTE.
   - OTHER THAN HYPOXIA, EPO ALSO CAN BE INCREASED IN A HIGH ALTITUDE SITUATION.

Question 12

BRIEFLY DESC THE NEED OF VITAMIN IN ERYTHROPOIESIS.

Answer 12

• VITAMINS ARE ONE OF THE NECESSARY FACTOR FOR ERYTHROPOIESIS.
• ONE OF THE VITAMIN THAT IS NEEDED IS VITAMIN B.
• DEFICIENCY OF VITAMIN B CAN LEAD TO ANAEMIA AS WELL AS PALLEGRA
• THEN THERE IS VITAMIN C AND D.
• DEFICIENCY OF VITAMIN C CAN LEAD TO ANAEMIA AND SCURVY.
• WHILE DEFICIENCY OF VITAMIN D, IT CAN LEAD TO RICKETS
• LASTLY, IT ALSO REQUIRE VITAMIN E IN WHICH DEFICIENCY OF VITAMIN E CAN LEAD TO MALNUTRITION.

Question 13

STATE THE IL THAT IS NEEDED FOR ERYTHROPOIESIS.

Answer 13

IL 3
IL 6
IL 11

Question 14

THROXINE CAN STIMULATE AND (ACCELERATE/DELAYED) THE ERYTHROPOIESIS.

Answer 14

ACCELERATE

Question 15

STATE THE FACTORS THAT IS NECESSARY FOR MATURATION OF RBC

Answer 15

VITAMIN B12
FOLIC ACID
INTRINSIC FACTOR

Question 16

BRIEFLY DESC THE NEED OF VITAMIN B 12 IN THE MATURATION OF RBC.

Answer 16

VITAMIN B12:
- NEEDED IN MATURATION OF RBC BY TRANSPORTING IT INTO THE BM
- CAN BE OBTAIN FROM THE DIET
- LACK OF VITAMIN B12 CAN -> FAILURE OF MATURATION OF CELL AND REDUCTION IN CELL DIVISION -> PERNICIOUS ANAEMIA
- STORED MAINLY IN THE LIVER AND SOME IN THE MUSCLE
- IMPORTANT FOR THE SYNTHESIS OF DNA OF RBC.

Question 17

BRIEFLY DESC THE NEED OF INTRINSIC FACTOR IN THE MATURATION OF RBC.

Answer 17

INTRINSIC FACTOR:
- PRODUCED IN THE GASTRIC MUCOSA IN THE PARIETAL CELL OF GASTRIC GLANDS
- LACK OF INTRINSIC FACTOR -> LACK OF ABSORPTION OF VITAMIN B12 -> PERNICIOUS ANAEMIA
- DEFICIENCY CAN OCCUR IN CASE OF:
1. SEVERE GASTRITIS
2. ULCER
3. GASTRECTOMY

Question 18

BRIEFLY DESC THE NEED OF FOLIC ACID IN THE MATURATION OF RBC.

Answer 18

FOLIC ACID:
- NEEDED FOR THE SYNTHESIS OF DNA IN RBC
- ABSENCE OF FOLIC ACID -> SYNTHESIS OF DNA REDUCED -> FAILURE OF MATURATION -> MEGALOBLASTIC ANAEMIA.

Question 19

LEUKOPOIESIS IS ACTIVATED BY SPECIFIC CHEMICALS IN RESPONSE TO

Answer 19

INFX
TOXINS
TUMOR CELLS

Question 20

GRANULOCYTE HAVE ___ LIFE SPAN WHICH ARE ___

Answer 20

SHORTER
5 TO 9 DAYS

Question 21

AGRANULOCYTE MAY LIVE ___ DEPENDING ON THE TYPE.

Answer 21

DAYS TO YEARS

Question 22

STATE THE DEVELOPMENTAL PATHWAY OF THROMBOCYTE.

Answer 22

MEGAKARYOBLAST -> PROMEGAKARYOCYTE -> MEGAKARYOCYTE -> THROMBOCYTE.

Question 23

BRIEFLY DESC THE THROMBOPOIESIS.

Answer 23

THROMBOPOIESIS:
- REGULATED BY THE TPO, WHICH PRODUCED BY THE LIVER AND KIDNEYS
- STIMULATE THE PROLIFERATION OF MEGAKARYOCYTE AND MATURATION INTO PLT.