Question

Hemolytic disease of the newborn is most likely to occur with an Rh ____ mother and Rh _____ fetus. 
a. Positive; positive  b. Positive; negative   c. Negative; negative   d. Negative; positive 

All blood cells (red and white) are derived from a common ancestor cell known as a:  
a. Totipotent stem cell      d. Lymphoid stem cell 
b. Pluripotent hematopoietic stem cell.  e. Myeloid stem cell 
c. Umbilical stem cell 

Correctly route an RBC through the following structures starting in the right atrium. 
1) Left atrium      4) Left ventricle 
2) Right ventricle    5) Pulmonary artery 
3) Pulmonary vein 
a. 1, 2, 4, 5, 3    b. 2, 4, 5, 1, 3    c. 3, 4, 5, 1, 2    d. 2, 5, 3, 1, 4 

Arrange the following steps in the pathway of the conduction system of the heart in the correct sequence: 
1) AV node        3) AV bundle & bundle branches   
2) SA node        4) Purkinje fibers 
      a. 3, 1, 2, 4      b. 2, 1, 3, 4    c. 1, 2, 3, 4    d. 1, 3, 2, 4 

Answer 1

1 The right answer is Rh negative of the mother and Rh positive of the father.
Haemolytic Newborn Disease (NHHN), which is associated with alloimmunization against RH, also MNS, KELL, DUFFY and JK antigens, is generally much more severe than that due to anti-A or anti-B. This disease is the consequence of the passage through the placenta of the antibodies of the mother who will attach to the red blood cells of the newborn possessing the antigen (that the mother does not possess, like Rhesus antigen). These antibodies are necessarily IgG type antibodies, mainly IgG1 because the IgM antibodies do not pass the placental barrier.

2. The right answer is the pluripotent hematopoietic stem cell (also called HSC).
Totipotent stem cell could be a right answer too since it is the stem-cell which all the cell organism derives from.
Lymphoid and myeloid stem cell concerns each a part of the white blood cells.
Umbilical stem cell produces only the cells of the umbellic cord.

3. The route of the RBC in the organism is: Starting from the right atrium, the deoxygenated blood that comes from the vena cava goes next in the right ventricle, to be ejected in the pulmonary artery to go to the lung to be re-oxygenated, than goes back through the pulmonary vein to the right in the left atrium than the left ventricle, and finally will be ejected again in the systemic arteries and capillaries to give supplies to the organism cells.
So the right answer is D

4. The right answer is B
The electric current is born at a precise point of the heart (of the order of a few millimeters in diameter), called sinus node (SA node), located at the top of the right atrium.This source consists of a cluster of cells capable of producing an electric current of a few millivolts. Starting from the sinus node, the current propagates in an oil spot in the cardiac muscle. It circulates in the 2 atria to their base, causing their contraction. This base, it converges to the septum separating atria and ventricles, at the level of an electrical relay called atrioventricular node (AV node).From the atrioventricular node, the impulse progresses simultaneously in the 2 ventricles, the right and the left, taking very fast conductive pathways (the Hys beam  and the Purkinje network), to the tip heart, causing contraction of the ventricles.