Blood

Question 1

List the roles that blood plays in the human body relating to homeostasis?

Answer 1

1. Transport: brings various substances to and from cells
2. immunological function: includes circulation of WBC and detection of foreign material by antibodies
3. Coagulation
4. Messenger function: transport hormones
5. Regulating body PH
6. Regulating core body temperature
7. Hydraulic functions: regulation of colloidal osmotic pressure

Question 2

Divide the components of blood into two portions, and give their approximate percentage volumes?

Answer 2

Plasma: 55%

Formed elements: 45%

Question 3

List the components of blood plasma, noting that it is almost identical to interstitial fluid with the exception of its protein content.

Answer 3

Plasma: protein + water + other solutes

interstitial fluid: does not contain protein

Question 4

Divide the proteins of plasma into three groups, giving a major function to each group.

Answer 4

Plasma proteins (made in liver)

1. Albumins (54%)- produced by liver, they transports several steroids and fatty acids
2. Fibrinogen (7%)- are clotting proteins that decrease blood loss when a blood vessel is injured
3. Globulins (38%)- Produced by liver & plasma cells (cell derived from B lymphocytes). Antibodies help attack viruses & bacteria

Question 5

Describe the structure and function of erythrocytes (RBC) and give a typical value for red blood cell count.

Answer 5

the hemoglobin within the RBCs transports most of the oxygen and part of the carbon dioxide in the blood.

females: 38%-46%
males: 42%-54%

Question 6

Name the structures and describe the steps involved in blood cell formation in the fetus and adults (including the name of the non mature cells).

Answer 6

RBC: pluripotent stem cell -> prorythroblast -> erythroblast
-> normoblast -> reticulocyte (w/o nucleus) -> erythrocyte

stem cell produces myeloid and lymphoid cells

myeloid produces: monocyte, neutrophil, eosinophil, basophil, platelets

lymphoid produces: B-cell, T-cell, natural killer

Question 7

Describe the mechanism which controls the number of circulating red blood cells, mentioning kidneys, erythropoietin, concentration of oxygen, spleen, liver, bone marrow and hematopoiesis.

Answer 7

low 02 levels -> kidneys produce EPO -> increased erythropoeisis production in blood -> new RBC’s enter bloodstream -> old blood cells eaten by macrophages -> heme or globin

heme -> bilirunin + iron

globin -> amino acids

Question 8

Predict the effect on red blood cell count of:

(a) a lack of kidney function
(b) living at high altitude, where oxygen concentration is lower than at sea level.

Answer 8

lack of kidney function: erytheropoetin (EPO) is produced in kidneys which increases production of RBC’s. would = decrease in RBC count.

High altitude: low oxygen concentration would = increase in EPO which would increase RBC count

Question 9

myeloid produces?

Answer 9

monocyte, neutrophil, eosinophil, basophil, platelets

Question 10

ymphoid produces?

Answer 10

B-cell, T-cell, natural killer