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Why wouldn’t the answer be A ?
Original post by mh2410
Why wouldn’t the answer be A ?


because a pathogen can't have an antibody, P, on it's surface?
Also, T helper cells stimulate B cells so they divide into plasma cells that produce antibodies, T helper cells don't have anything directly to do with antibodies afaik
Reply 3
Original post by Aloe Striata
because a pathogen can't have an antibody, P, on it's surface?

But a lymphocyte can be attached on its surface for the phagocytes to take it in
An antibody is an enzyme produced in response to an antigen on the surface of the pathogen.
The antigen is a surface protein that is present on the pathogen's surface, often with a function that aids its virulence.

T-helper cells play a key role in mediating the immune response, by producing immune factors that activate other immune cells.

B-lymphocytes manufacture antibodies which bind to the antigens, marking them for destruction by other immune cells including phagocytes.

Hope this helps.
Original post by mh2410
But a lymphocyte can be attached on its surface for the phagocytes to take it in

No but why would a lymphocyte be attached to the surface of the pathogen? The lymphocyte (depends on which you're talking about) ENGULFS the pathogen or produces the antibodies (B lymphocytes) And let's suppose for a second that the pathogen did have a lymphocyte on it's surface, even then A would be wrong, because a lymphocyte is a white blood cell, it's not an antibody
Edit: sorry, my bad, didn't mean to say that lymphocytes engulf pathogens. they don't
(edited 2 years ago)
Original post by mh2410
But a lymphocyte can be attached on its surface for the phagocytes to take it in

Nope, the lymphocyte manufactures and releases antibodies which bind to the antigen, thus marking it for destruction by the phagocyte.
Reply 7
Original post by Aloe Striata
No but why would a lymphocyte be attached to the surface of the pathogen? The lymphocyte (depends on which you're talking about) ENGULFS the pathogen or produces the antibodies (B lymphocytes) And let's suppose for a second that the pathogen did have a lymphocyte on it's surface, even then A would be wrong, because a lymphocyte is a white blood cell, it's not an antibody
Edit: sorry, my bad, didn't mean to say that lymphocytes engulf pathogens. they don't

I meant antibodies
Reply 8
Original post by dacb2f2dd4
Nope, the lymphocyte manufactures and releases antibodies which bind to the antigen, thus marking it for destruction by the phagocyte.

Yes precisely what I meant
Original post by mh2410
I meant antibodies

Antibodies attach to the pathogen to destroy it or be marked for destruction, they’re not a permanent feature of the pathogen as the question asks
Reply 10
Original post by dacb2f2dd4
An antibody is an enzyme produced in response to an antigen on the surface of the pathogen.
The antigen is a surface protein that is present on the pathogen's surface, often with a function that aids its virulence.

T-helper cells play a key role in mediating the immune response, by producing immune factors that activate other immune cells.

B-lymphocytes manufacture antibodies which bind to the antigens, marking them for destruction by other immune cells including phagocytes.

Hope this helps.

So basically its just a factor that helps to stimulate immune response ( ex,it triggers B lympcutye to secrete amtboies )
Original post by mh2410
Yes precisely what I meant

But the antibody doesn't attach to the surface of the cells.
It attaches to the surface protein (antigen). The antigen is attached to the surface of the pathogen, and the antibody attaches onto than. Therefore A cannot be correct, as the antibody does not attach directly to the surface of the pathogen.
Additionally, T-helper cells cannot produce antibodies, only signalling molecules to mediate the immune response.

Hope this clarifies the point you're finding confusing.
Original post by mh2410
So basically its just a factor that helps to stimulate immune response ( ex,it triggers B lympcutye to secrete amtboies )

So the surface protein on the pathogen usually serves a purpose for the pathogen itself - often it aids in entering human cells etc, in order to cause infection.
These surface proteins are recognised by the t-cells as 'foreign', as they are not normal human proteins.
The t-cells produce factors which activate the immune response.
The b-cells produce antibodies specific to the foreign antigens.
These bind to the antigens and mark the cells for destruction.

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