Jun 22, 2009
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1.Which of the following is the major intracellular buffer?
Phophate ? or Bicarbonate?

2. Which of the following cells creates antibody-producing plasma cells?
I thought it is B cells. But the answer key says it is cytotoxic T cells. Is it?

3. The fusion of male and female pronuclei characterizes the final step of
A. ovulation
B. Sperm meiosis
C.Gametogenesis
D.egg muturation
E.fertilization

I thought it is E. but the answer key says it is A.

4. Growth (increased length) of long bones originates in which of the following regions? I thought it is Metaphysis. But key says it is epiphysis. :(


What do you think for these qs?

I think this one has several errors. :confused:
 

OU11BB

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1.Which of the following is the major intracellular buffer?
Phophate ? or Bicarbonate?

2. Which of the following cells creates antibody-producing plasma cells?
I thought it is B cells. But the answer key says it is cytotoxic T cells. Is it?

3. The fusion of male and female pronuclei characterizes the final step of
A. ovulation
B. Sperm meiosis
C.Gametogenesis
D.egg muturation
E.fertilization

I thought it is E. but the answer key says it is A.

4. Growth (increased length) of long bones originates in which of the following regions? I thought it is Metaphysis. But key says it is epiphysis. :(


What do you think for these qs?

I think this one has several errors. :confused:
pretty sure the first is phosphate buffers, as for to the T cells are thymus derived and i thought that the bone marrow cells produce plasma and memory cells. it seems like the T helper (Th2)may play a role in B cell but i will need to look. #3 i would have guess fertilization, and 4 would have picked epiphyseal plates (growth plates) so i would have gone with epiphysis.
 

TexasOMFS

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IntRAcellular buffer is phosphoric acid (phosphate) while intERcellular buffer is bicarbonate
B lymphocytes give rise to plasma cells.
3. should definitely be E. Fertilization
Epiphyseal plates
ADA seriously needs a test-proofreader.
 
Last edited:

UndergradGuy7

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B cells make plasma cells. And helper T cells might help to make plasma cells.

I don't know anything about phosphate as a buffer, but bicarbonate is definately a buffer with respiration, CO2.
Edit: I did some googling it seems as though bicarbonate is the main extracellular buffer. Since it is in the blood circulating etc. The main intracellular buffer is phosphate though. Link http://books.google.com/books?id=erKJnpXOTi4C&pg=PA30&lpg=PA30&dq=h3po4+intracellular+buffer&source=bl&ots=cgeB7jYL8r&sig=EFlIdOOqtcQ7Zfqb__5vf57fB9o&hl=en&ei=XyioS-zbBpSmNoXEhL4B&sa=X&oi=book_result&ct=result&resnum=7&ved=0CCAQ6AEwBg#v=onepage&q=&f=false

For the bone growth, bone growth happens in the metaphysis region, and more specifically there is a place in the metaphysis region called the epiphyseal plate where it happens. I guess this is a bad question. Could be either one depending on how specific they want the answer.

Is this the sample exam that is free or the one you have to order?
 
Last edited:

kpanesar

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i agree with most of you and some of these questions are also tested in the destroyer

1. phosphate is intracellular buffer and carbonate is extracellular

2. B-cells need to be activated by T-cells in order to differentiate into other specialized cells.

3. It has to be E. Ovulation is characterized by a surge in LH. Sperm meiosis would be characterized by 4 equal haploid germ cells. Gametogenesis is just a generic term for diploid/haploid differentiating into haploid gametes. Egg maturation is the final step of Oogenesis and needs to occur before fusion with male gametes.

4. Yeah same as above. Long bones have epiphyseal growth plates.
 

akeurogh

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i agree with most of you and some of these questions are also tested in the destroyer

1. phosphate is intracellular buffer and carbonate is extracellular

2. B-cells need to be activated by T-cells in order to differentiate into other specialized cells.

3. It has to be E. Ovulation is characterized by a surge in LH. Sperm meiosis would be characterized by 4 equal haploid germ cells. Gametogenesis is just a generic term for diploid/haploid differentiating into haploid gametes. Egg maturation is the final step of Oogenesis and needs to occur before fusion with male gametes.

4. Yeah same as above. Long bones have epiphyseal growth plates.


agreed!
 

dentalWorks

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answers = blue

1.Which of the following is the major intracellular buffer?
Phophate ? or Bicarbonate?
There is a destroyer question about this, Im pretty sure its phosphate. Bicarbonate is the buffer in your blood (aka extracellular buffer)

2. Which of the following cells creates antibody-producing plasma cells?
I thought it is B cells. But the answer key says it is cytotoxic T cells. Is it?
Dunno this one

3. The fusion of male and female pronuclei characterizes the final step of
A. ovulation
B. Sperm meiosis
C.Gametogenesis
D.egg muturation
E.fertilization

I thought it is E. but the answer key says it is A.
This is a nice question, It has to do with you underestanding oogenesis. Remember with oogenesis (oogenesis = creation of egg cell), the egg will stay halted in metaphase II UNTIL fertilized by sperm.

4. Growth (increased length) of long bones originates in which of the following regions? I thought it is Metaphysis. But key says it is epiphysis. :(
I am 100% sure of this, Its epiphyseal plates. These are regions located at the ends of long bones. they are cartilage, they remain so until the child is fully developed into an adult in which case the epiphyseal plates harden and turn to bone and the only thing left in them is the "epiphyseal line".... I know this cause we covered this pretty heavy in my 2 classes (anatomy and histology)


What do you think for these qs?

I think this one has several errors. :confused:
I think they are all correct, I don't see any errors, except the immunology one, I have no idea if its right or wrong
 

AmpedUp

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#3's answer is definitely wrong...wow!

ovulation doesn't mean sperm and egg will join...it's definitely Fertilization.
 

TeethandLakers

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This is a nice question, It has to do with you underestanding oogenesis. Remember with oogenesis (oogenesis = creation of egg cell), the egg will stay halted in metaphase II UNTIL fertilized by sperm
#3 is Fertilization for sure. The egg will stay halted in metaphase II until Sperm ENTRY not fertilization. Once the sperm enters, the egg goes through the slow polyspermy reaction and gives off its 2nd (1N/1C) polar body. It is then that the sperm's centriole brings the pro-nuclei together and completes fertilization.
 

K Niner

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Since I've taken immunology I can tell you for sure on that one. B cells are the precursor to plasma cells. They are made in the bone marrow also, while t cells are from the thymus. T cells and b cells are both called lymphocytes. This might clear up some of the confusion

However t cells may be needed (can't remember) to tell the b cells to differentiate into plasma cells. Since you didn't copy the question verbatim I can't tell you the definite answer.
 
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Since I've taken immunology I can tell you for sure on that one. B cells are the precursor to plasma cells. They are made in the bone marrow also, while t cells are from the thymus. T cells and b cells are both called lymphocytes. This might clear up some of the confusion

However t cells may be needed (can't remember) to tell the b cells to differentiate into plasma cells. Since you didn't copy the question verbatim I can't tell you the definite answer.

Which of the following creates works of art? The artist or the canvas? If you say artist, your same logic is why the question's answer is T-cells.

Even so, I still disagree with the specific answer itself. Helper T-cell cytokine signaling activates B-cell proliferation, not cytotoxic T-cells.