question from the ADA 2009 test

[runner222]

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17. which of the following cells creates antibody-producing plasma cells?
A. B-cells
B. T-helper cells
C. cytotoxic T cells
D. Macrophages
E. Natural killer cells

Maybe im just being really stupid but I thought it was B cells. ADA's answer is C.

Any input?

 

[267862]

dude... it should be B cells. Cyt T cells are "killer"cells as i'm sure everyone knows. that's messed up

 

[prsndwg]

17. which of the following cells creates antibody-producing plasma cells?
A. B-cells
B. T-helper cells
C. cytotoxic T cells
D. Macrophages
E. Natural killer cells

Maybe im just being really stupid but I thought it was B cells. ADA's answer is C.

Any input?

I thought both A and B used antibody.. I dont remember cytotoxic T cell using antibody!!
how is the overall difficulty of that test? Is it worth getting? How long it took for you to receive it?

 

[runner222]

i don't know if it's worth it. i feel like the ADA should put out a pretty dang good test since that's all they give us but i saw a few errors, such as asking the same question twice.

It also had questions that I had never seen before in any of the achiever tests or topscore or kaplan. Such as ochem nomenclature involving lamda with nonstandard bonding.

heres another question if anyone has some input:
Which of the following is the major intracellular buffer?
A. Tris
B. Acetate
C. Phosphate
D. Bicarbonate
E. calcium carbonate.

I thought bicarbonate buffering was in the blood and phosphate was intracellular, but the answer is D. Anyone?

 

[runner222]

haha sorry to keep posting questions but bio isn't my strong suit.

The fusion of male and female pronuclei characterizes the final step of
A. Ovulation
B. sperm meiosis
C. gametogenesis
D. Egg maturation
E. Fertilization

Help??...

 

[prsndwg]

alright so, i see errors, The Q about buffer, bicarbonate is for blood and phosphate is for intracellular. So that is an error.

Is last Q you posted, Fertilization?

 

[runner222]

No. they said ovulation. haha screw this test

 

[runner222]

im pretty sure that is the definition of fertilization

 

[TexasOMFS]

Looks like a lousy test man. It is definitely B cells, phosphoric acid buffer, and fertilization. Did you say you had to pay for this test? Lmao.

 

[prsndwg]

No. they said ovulation. haha screw this test

May be they are testing your knowledge of whether their answer is true or false? 🙄

 

[runner222]

do you think they will give me my money back? i've found two ochem issues so far. Like way wrong. like wrong number of carbons.

 

[299678]

17. which of the following cells creates antibody-producing plasma cells?
A. B-cells
B. T-helper cells
C. cytotoxic T cells
D. Macrophages
E. Natural killer cells

Maybe im just being really stupid but I thought it was B cells. ADA's answer is C.

Any input?

It's not mistake. That's exactly right answer
B cell produce antibodies, but cytotoxic t-cells through the release of interleukins can also stimulate the proliferation of B-cells and plasma cells, so Cytotoxic t cell create antibody producing plasma cells. Read question carefully, question is not asking which cell produce antibodies, but which cell produce antibody producing plasma cells. In other words, which cell produce B cell?

so answer is cytotoxic T cell

 

[299678]

i don't know if it's worth it. i feel like the ADA should put out a pretty dang good test since that's all they give us but i saw a few errors, such as asking the same question twice.

It also had questions that I had never seen before in any of the achiever tests or topscore or kaplan. Such as ochem nomenclature involving lamda with nonstandard bonding.

heres another question if anyone has some input:
Which of the following is the major intracellular buffer?
A. Tris
B. Acetate
C. Phosphate
D. Bicarbonate
E. calcium carbonate.

I thought bicarbonate buffering was in the blood and phosphate was intracellular, but the answer is D. Anyone?

Internal fluid of cell, intracellular buffer - Phosphate Buffer (H2PO4^-)
Extracellular fluid buffer - Bicarbonate (HCO3^-)

so intracellular buffer is phosphate. Also Plasma, the liquid portion of blood, is part of the extracellular fluid (ECF) and question is asking Major intracellular buffer.

But the question didn't specify what organism?

 

[299678]

haha sorry to keep posting questions but bio isn't my strong suit.

The fusion of male and female pronuclei characterizes the final step of
A. Ovulation
B. sperm meiosis
C. gametogenesis
D. Egg maturation
E. Fertilization

Help??...

A pro-nucleus is the nucleus of a sperm or an egg cell during the process of fertilization, after the sperm enters the ovum, but before they fuse. So, obviously fusion of pro-nucleus is the final step of fertilization

 

[runner222]

I appreciate your help but im not sure that I agree with you on the plasma cell question. In Campbells on pg 908 and 910, it states that "selected B cells generate antibody-secreting effector B cells, called plasma cells." I agree that T cells can assist, but pg 910 shows that helper T cells play a greater role in inducing the differentiation of B cells.

 

[Denty8]

10 character

 

[prsndwg]

I'm wondering where you read this; I have read Kaplan and Cliff's and don't remember reading about phosphate buffering at all. What was your resource?

destroyer

 

[lovelyinpink11]

It's not mistake. That's exactly right answer
B cell produce antibodies, but cytotoxic t-cells through the release of interleukins can also stimulate the proliferation of B-cells and plasma cells, so Cytotoxic t cell create antibody producing plasma cells. Read question carefully, question is not asking which cell produce antibodies, but which cell produce antibody producing plasma cells. In other words, which cell produce B cell?

so answer is cytotoxic T cell

You're describing the function of a helper T cell.

 

[RDH]

It's not mistake. That's exactly right answer
B cell produce antibodies, but cytotoxic t-cells through the release of interleukins can also stimulate the proliferation of B-cells and plasma cells, so Cytotoxic t cell create antibody producing plasma cells. Read question carefully, question is not asking which cell produce antibodies, but which cell produce antibody producing plasma cells. In other words, which cell produce B cell?

so answer is cytotoxic T cell

+1... Helper t cell are what bind to macrophages which display MHC markers these helper cell activate interlukins such as lymphokines which activate the Cytotoxic cells. Cytotoxic kill nonself cells and Activate Bcell response to produce antibody via plasma cells and produce memory cells for future protection

 

[lovelyinpink11]

+1... Helper t cell are what bind to macrophages which display MHC markers these helper cell activate interlukins such as lymphokines which activate the Cytotoxic cells. Cytotoxic kill nonself cells and Activate Bcell response to produce antibody via plasma cells and produce memory cells for future protection

Tc cells are effector/killing cells...they do not activate B cells. It wouldn't make sense for a Tc cell to activate B cells, because Tc cells kill intracellular infections/viruses, while antibodies work on only extracellular antigens and wouldn't be able to reach the site of infection. Helper T cells activate the effector mechanisms of Tc cells, but when they interact with B cells, they release the cytokines that help create plasma cells. Tc cells create their own memory cells, but they are not antibody plasma cells. I just took immunology and looked it up on the web to make sure.

 

[winnie bear]

haha sorry to keep posting questions but bio isn't my strong suit.

The fusion of male and female pronuclei characterizes the final step of
A. Ovulation
B. sperm meiosis
C. gametogenesis
D. Egg maturation
E. Fertilization

Help??...

Don't be! Continue to post...I'm sure there are others like myself who are studying from your Q's too. 👍

 

[prsndwg]

I think we have to wait for UCB05 for clarification🙄

 

[akeurogh]

Tc cells are effector/killing cells...they do not activate B cells. It wouldn't make sense for a Tc cell to activate B cells, because Tc cells kill intracellular infections/viruses, while antibodies work on only extracellular antigens and wouldn't be able to reach the site of infection. Helper T cells activate the effector mechanisms of Tc cells, but when they interact with B cells, they release the cytokines that help create plasma cells. Tc cells create their own memory cells, but they are not antibody plasma cells. I just took immunology and looked it up on the web to make sure.

this is exactly the answer. It wouldn't make sense for cyt t cells to stimulate B cells.

 

[clubwestpua]

bump

Another question I would like to share.

19. Developing organisms have negative entropy, and what do they use to aid this process?

A. Enzymes
B. Violating Second Law of thermodynamics
C. Using external source of energy
D. Concentrating their molecules and reverse the flow of energy
E. Creating Energy

How is the answer (E)? E is violating First Law of Thermodynamics. Therefore I thought the answer was (C).