Login

Welcome, Guest. Please login or register.

March 29, 2024, 01:41:26 am

Author Topic: VCE Biology Question Thread  (Read 3570615 times)  Share 

0 Members and 5 Guests are viewing this topic.

RazzMeTazz

  • Victorian
  • Forum Leader
  • ****
  • Posts: 673
  • Respect: 0
Re: VCE Biology Question Thread
« Reply #1890 on: June 11, 2014, 08:07:45 pm »
0
Do red blood cells have any MHC marker proteins on their surface?

Reus

  • Victorian
  • ATAR Notes Superstar
  • ******
  • Posts: 2125
  • Respect: +135
Re: VCE Biology Question Thread
« Reply #1891 on: June 11, 2014, 08:14:47 pm »
0
Do red blood cells have any MHC marker proteins on their surface?
Well if we're talking about MHC #1, no, as they are only found on cells with a nucleus. However MHC #2 are found on leucocytes (red blood cells) for instance on macrophages and dendritic cells.
2015: Bachelor of Science & Bachelor of Global Studies @ Monash University

nhmn0301

  • Victorian
  • Forum Obsessive
  • ***
  • Posts: 379
  • Respect: +15
  • School: The University of Melboure
  • School Grad Year: 2017
Re: VCE Biology Question Thread
« Reply #1892 on: June 11, 2014, 08:55:58 pm »
0
Well if we're talking about MHC #1, no, as they are only found on cells with a nucleus. However MHC #2 are found on leucocytes (red blood cells) for instance on macrophages and dendritic cells.
Leuko - is a Greek word, meaning "white". Hence, Leukocyte means White Blood Cell. White blood cells have MHC II markers, but not red blood cell. Red blood cells don't have markers on them.
2015-2017: Bachelor of Biomedicine

vox nihili

  • National Moderator
  • Great Wonder of ATAR Notes
  • *****
  • Posts: 5343
  • Respect: +1447
Re: VCE Biology Question Thread
« Reply #1893 on: June 11, 2014, 09:47:43 pm »
+2
Leuko - is a Greek word, meaning "white". Hence, Leukocyte means White Blood Cell. White blood cells have MHC II markers, but not red blood cell. Red blood cells don't have markers on them.

Not all leukocytes have class II molecules. Only APCs do. The rest is completely correct though. Also worth noting that all leukocytes carry MHC class I molecules.
2013-15: BBiomed (Biochemistry and Molecular Biology), UniMelb
2016-20: MD, UniMelb
2019-20: MPH, UniMelb
2021-: GDipBiostat, USyd

Reus

  • Victorian
  • ATAR Notes Superstar
  • ******
  • Posts: 2125
  • Respect: +135
Re: VCE Biology Question Thread
« Reply #1894 on: June 11, 2014, 09:53:16 pm »
+1
Leuko - is a Greek word, meaning "white". Hence, Leukocyte means White Blood Cell. White blood cells have MHC II markers, but not red blood cell. Red blood cells don't have markers on them.
Oh wow! Can't believe I just said red blood cells were leucocytes... Haha my teacher would kill me!
Sorry for that! Was completely thinking of white blood cells when MHC markers came to my head.
2015: Bachelor of Science & Bachelor of Global Studies @ Monash University

nhmn0301

  • Victorian
  • Forum Obsessive
  • ***
  • Posts: 379
  • Respect: +15
  • School: The University of Melboure
  • School Grad Year: 2017
Re: VCE Biology Question Thread
« Reply #1895 on: June 11, 2014, 10:17:05 pm »
0
This question probably a bit outside the course but oh well
Since immunoglobulin is really specific and there are seem to be infinite variety of them inside our body. Hence, according to a bit of my research, are they produced by recombination-activating genes? If so, for the coding message to be read and produce antibodies, the cell must carry synthesis of protein from transcription and translation right? Meaning for 1 gene, we can code for 1 polypeptide = possible many proteins (i.e immunoglobulin in this case) ? The final point I am trying to ask is: when we produce an antibody initially, we don't just produce only 1 big molecule of antibody but many of them from the same type?
Hope this question makes sense, thanks for help!
2015-2017: Bachelor of Biomedicine

Jason12

  • Victorian
  • Forum Obsessive
  • ***
  • Posts: 497
  • Respect: +15
  • School: WCC
  • School Grad Year: 2014
Re: VCE Biology Question Thread
« Reply #1896 on: June 11, 2014, 10:24:35 pm »
0
are antibodies produced by the b cell or the plasma cell? Which one is more correct? My teacher says only plasma cells
2014 ATAR - 88

2015 sem 1 - Bachelor of Business (Accounting/Banking & Finance) - Monash

2015 sem 2 - Present: Bachelor of Commerce (Accounting/Finance), Diploma of Languages (Chinese) - Monash

nhmn0301

  • Victorian
  • Forum Obsessive
  • ***
  • Posts: 379
  • Respect: +15
  • School: The University of Melboure
  • School Grad Year: 2017
Re: VCE Biology Question Thread
« Reply #1897 on: June 11, 2014, 10:32:55 pm »
0
are antibodies produced by the b cell or the plasma cell? Which one is more correct? My teacher says only plasma cells
When B cells are activated, they differentiate into plasma cells and B-memory cells. Plasma cells produce free-floating anitbodies and release into the bloodstream, they have a pretty short life span.
2015-2017: Bachelor of Biomedicine

Reus

  • Victorian
  • ATAR Notes Superstar
  • ******
  • Posts: 2125
  • Respect: +135
Re: VCE Biology Question Thread
« Reply #1898 on: June 11, 2014, 10:35:43 pm »
0
are antibodies produced by the b cell or the plasma cell? Which one is more correct? My teacher says only plasma cells
B cells posses a specific antibody (when binded to an antigen), then proliferates into B plasma cells that produce the specific antibodies for that particular antigen.
So in a sense, B plasma cells produce them.
I think your teacher is right
2015: Bachelor of Science & Bachelor of Global Studies @ Monash University

simpak

  • Victorian
  • ATAR Notes Legend
  • *******
  • Posts: 3587
  • Respect: +376
Re: VCE Biology Question Thread
« Reply #1899 on: June 11, 2014, 10:43:32 pm »
+1
This question probably a bit outside the course but oh well
Since immunoglobulin is really specific and there are seem to be infinite variety of them inside our body. Hence, according to a bit of my research, are they produced by recombination-activating genes? If so, for the coding message to be read and produce antibodies, the cell must carry synthesis of protein from transcription and translation right? Meaning for 1 gene, we can code for 1 polypeptide = possible many proteins (i.e immunoglobulin in this case) ? The final point I am trying to ask is: when we produce an antibody initially, we don't just produce only 1 big molecule of antibody but many of them from the same type?
Hope this question makes sense, thanks for help!

For one gene you can normally encode one polypeptide but for the genes encoding antibodies or TCRs you can encode many different varieties of polypeptides from the same basic 'gene'. In the germline (eg stem cells) you have many different DNA 'segments' that might be chosen to contribute to an antibody - only one of a large group of these varieties will be chosen by the developing B cell or T cell and this gives them a unique and specific receptor from the same original germline DNA.  But in each individual cell, the DNA has been changed from what was in the zygote that gave rise to all cells - special immunity enzymes actually modify the genome of the T and B cells so that they can express only one TCR or antibody each.  Thus, stem cells have the capacity to produce many different antibodies somewhere down the line but once they actually start differentiating to a lymphocyte they become restricted to producing only one antibody through the modification of their DNA coding sequences (basically cutting and pasting of DNA).
So overall, the antibody gene locus can give rise to every possible antibody.
But in an individual cell, the 1 gene = 1 polypeptide/protein (interchangeable terms for these in this context) rule still applies because it's the gene that got changed, the change doesn't occur at the protein level.

Does that answer your question?  I'm not sure, I think I understood what you were trying to ask but I could be wrong.

It's definitely outside the scope of this course.
2009 ENTER: 99.05
2014: BSci Hons (Microbiology/Immunology) at UoM
2015+: PhD (Immunology) at UoM

Jason12

  • Victorian
  • Forum Obsessive
  • ***
  • Posts: 497
  • Respect: +15
  • School: WCC
  • School Grad Year: 2014
Re: VCE Biology Question Thread
« Reply #1900 on: June 11, 2014, 10:44:55 pm »
0
B cells posses a specific antibody (when binded to an antigen), then proliferates into B plasma cells that produce the specific antibodies for that particular antigen.
So in a sense, B plasma cells produce them.
I think your teacher is right

do T helper cells activate the B cells dividing or what activates the B cell to proliferate?
2014 ATAR - 88

2015 sem 1 - Bachelor of Business (Accounting/Banking & Finance) - Monash

2015 sem 2 - Present: Bachelor of Commerce (Accounting/Finance), Diploma of Languages (Chinese) - Monash

simpak

  • Victorian
  • ATAR Notes Legend
  • *******
  • Posts: 3587
  • Respect: +376
Re: VCE Biology Question Thread
« Reply #1901 on: June 11, 2014, 10:46:22 pm »
+1
This question probably a bit outside the course but oh well
Since immunoglobulin is really specific and there are seem to be infinite variety of them inside our body. Hence, according to a bit of my research, are they produced by recombination-activating genes? If so, for the coding message to be read and produce antibodies, the cell must carry synthesis of protein from transcription and translation right? Meaning for 1 gene, we can code for 1 polypeptide = possible many proteins (i.e immunoglobulin in this case) ? The final point I am trying to ask is: when we produce an antibody initially, we don't just produce only 1 big molecule of antibody but many of them from the same type?
Hope this question makes sense, thanks for help!

For one gene you can normally encode one polypeptide but for the genes encoding antibodies or TCRs you can encode many different varieties of polypeptides from the same basic 'gene'. In the germline (eg stem cells) you have many different DNA 'segments' that might be chosen to contribute to an antibody - only one of a large group of these varieties will be chosen by the developing B cell or T cell and this gives them a unique and specific receptor from the same original germline DNA.  But in each individual cell, the DNA has been changed from what was in the zygote that gave rise to all cells - special immunity enzymes actually modify the genome of the T and B cells so that they can express only one TCR or antibody each.  Thus, stem cells have the capacity to produce many different antibodies somewhere down the line but once they actually start differentiating to a lymphocyte they become restricted to producing only one antibody through the modification of their DNA coding sequences (basically cutting and pasting of DNA).
So overall, the antibody gene locus can give rise to every possible antibody.
But in an individual cell, the 1 gene = 1 polypeptide/protein (interchangeable terms for these in this context) rule still applies because it's the gene that got changed, the change doesn't occur at the protein level.

Does that answer your question?  I'm not sure, I think I understood what you were trying to ask but I could be wrong.

It's definitely outside the scope of this course.
2009 ENTER: 99.05
2014: BSci Hons (Microbiology/Immunology) at UoM
2015+: PhD (Immunology) at UoM

Reus

  • Victorian
  • ATAR Notes Superstar
  • ******
  • Posts: 2125
  • Respect: +135
Re: VCE Biology Question Thread
« Reply #1902 on: June 11, 2014, 10:47:04 pm »
0
do T helper cells activate the B cells dividing or what activates the B cell to proliferate?
Yes, T helper cells stimulate the activation of B cells differentiating into B memory and B plasma.
2015: Bachelor of Science & Bachelor of Global Studies @ Monash University

Jason12

  • Victorian
  • Forum Obsessive
  • ***
  • Posts: 497
  • Respect: +15
  • School: WCC
  • School Grad Year: 2014
Re: VCE Biology Question Thread
« Reply #1903 on: June 11, 2014, 10:48:47 pm »
0
what is the correct name for when a body overreacts to a harmless antigen? Allergic response, allergy, hypersensitivity?
2014 ATAR - 88

2015 sem 1 - Bachelor of Business (Accounting/Banking & Finance) - Monash

2015 sem 2 - Present: Bachelor of Commerce (Accounting/Finance), Diploma of Languages (Chinese) - Monash

RazzMeTazz

  • Victorian
  • Forum Leader
  • ****
  • Posts: 673
  • Respect: 0
Re: VCE Biology Question Thread
« Reply #1904 on: June 11, 2014, 10:49:02 pm »
0
Do helper T cells also stimulate cytotoxic T cells to proliferate into memory cytotoxic T cells and effector cytotoxic T cells?