W3006    Fall 2002       Physiology      Mini-Exam #4         NAME __________________________________

Circle all correct answers.   5 points for each answer,  which makes for a total of 75 points.  Everyone was given 5 free points, to make the exam equal 80 like the previous exams.

1.  _____ are the precursor cells of macrophages.
a. eosinophils   b. basophils   c.  neutrophils   d.  monocytes   e. lymphocytes

Both neutrophils and and monocytes can leave the blood and enter the tissues, but only the monocytes turn into macrophages. 

2.  The cells responsible for cell-mediated immunity are the
a.  B lymphocytes    b. plasma cells    c.  T lymphocytes     d. NK cells  
e. more than one of the above

See slide 3 in the last lecture 

3.  When an antigen is bound to an MHC I molecule, it can stimulate a
a. B cell     b.  plasma cell     c. helper T cell     d. cytotoxic T cell     e. NK cell  

MHC I is found on body cells, which display antigen when infected with virus, or mutated, which is recognized by TCR and CD8.

4.  A patient is not feeling sick, but goes for a routine exam, and blood is taken and analyzed.  The results show a high IgM level for the mumps antigen.  This would indicate that
a. The person has just recovered from mumps a few weeks earlier.
b. The person has recently been infected with mumps for the first time, but hasn’t yet developed symptoms.
c. The person had mumps a long time ago, and is now immune to mumps.
d. The person had mumps a long time ago, and has been recently infected with mumps a second time.
e. The person has some sort of mutation, because IgM is normally found only in exocrine secretions, not in the blood.

IgM is secreted into the blood in large amounts after first exposure to an antigen.  Much smaller amounts may be found in a secondary response, at which time IgG predominates.  IgA is found in exocrine secretions.

5. Norepinephrine stimulates  ____ receptors
a.  muscarinic  b. nicotinic   c.  adrenergic

 6.  Both cortisol and epinephrine 
a.  stimulate a cell-membrane receptor    b.  are released from the adrenal cortex   c. break down muscle protein
d.  increase blood glucose levels    e. increase fatty acids in the blood

7.  A person has a disorder in which the cells that express CD8 do not mature normally.  This person would be especially susceptible to    a. viral infections     b. bacterial infections      c.  infections or other traumas that would stimulate the inflammatory response

CD8 is found on cytotoxic T cells, which recognize cells of our body that are displaying a foreign protein, either because they've been infected by a virus, or because they're expressing a mutant protein. 

8.  A person with hay fever has localized edema in the tissues of the respiratory system.  Antihistamines may lessen this symptom by blocking histamine receptors on the
a.  lymphocytes      b.  mast cells      c.  macrophages     d. capillaries     e. fibroblasts

Histamine is secreted from mast cells and stimulates capillaries to increase the openings between adjacent epithelial cells, such that the capillaries are more porous, and more protein leaves the blood, with water following, causing the edema. 

 9.  ___Interferon_________ is released from virally-infected cells and inhibits multiplication of viruses in other cells.

 10.  Some kinds of bacteria, such as Staphylococcus aureus, release a protein called leukocidin which damages the cell membrane of phagocytes.  Which one type of cells are most likely to be affected by leukocidin?

a.  cytotoxic T cells     b.  plasma cells     c.  neutrophils      d. natural killer cells        e.  fibroblasts

 Neutrophils can phagocytize bacteria.

11.  Certain drugs are able to inhibit the activity of ACE (Angiotensin Converting Enzyme).  You would expect these ACE-inhibitors to be used when it’s desirable to 

a.  raise the sodium content of blood   b.  lower blood pressure   c. stimulate aldosterone secretion   d.  treat a person who can’t produce renin   e. treat a person who can’t produce angiotensinogen

 ACE activates angiotensin, which stimulates aldosterone release, which increases salt and water retention, and so raises blood pressure.  So inhibiting ACE would lower aldosterone secretion, lower the sodium content of blood, and lower blood pressure.  It would have no effect on people who can't produce renin or angiotensinogen, since these people would lack the substrate that it acts on (angiotensin I). 

12.  People who have survived polio are twice as sensitive to pain as normal people.  This may be explained in part by the finding that these people have lower than normal levels of
a.  pomc       b. renin      c. norepinephrine     d. vasopressin       e. acetylcholine  

POMC is a precursor to ACTH and also to endorphin, which suppresses sensations of pain.  Low pomc, less endorphin, higher sensation of pain. 

13.   The neurotransmitter in the sympathetic ganglia is ___acetylcholine_____________.

The ganglia is the region where the preganglionic neuron synapses on the postganglionic neuron, and ACh is the neurotransmitter in this synapse.   

14.    ___Perforin______  is released from both NK cells and cytotoxic  T cells.

15.   ___Complement_____  refers to a group of plasma proteins that, when activated produce a  cylindrical pore in bacterial cell membranes.