VCE Biology Questions Thread
what would be an adavantage of surpression immunotherapy?
For question 4c short answer 2022 biology NHT, how would you answer the question would you outline the humoral immune response?
butterfly13579 allows specific cells in the immune system (basically autoreactive B and T cells that recognise self cells as foreign) to be suppressed for those who have autoimmune diseases without the entire immune system being compromised like immunosuppressants do.
what is the way autoimmune disease treated with monoclonal antibodies
chemistry1111 I think you might be referring to part D here
For part C though, you’d just have to say preventative measures to reduce transmission of a respiratory disc ease ex- wearing face masks, not sharing the food/drink which they did, or using handsanitiser to kill viral particles on their hands
For part D - you’d have to specific to Pat’s case - because she’s already received her vaccine - the humoral immune response would’ve kinda already occurred before she got infected at the movie theatres- so now its more like the response she’d have with a booster shot with the second exposure to the same pathogen
So you might modify your response like this
- The viral antigen would be recognised as “non self” by the T helper cells which would release cytokines
- Activating the B and T memory cells that were previously produced from the vaccine
- This may cause memory cells to rapidly differentiate into plasma cells
- That secrete large numbers of antibodies at a much faster rate than the first exposure to the flu virus
- Stimulating a stronger, faster greater immune response as the antibodies would quickly agglutinate the viral pathogens making it easier for phagocytes too detect, engulf and destroy them
- Preventing Pat from being infected and developing symptoms of the flu
Hope this helps and is concise enough 
Smartiestarz thank you
whats the difference between validity, and accuracy
chemistry1111 validity = are you measuring what you want to measure? and can your results be applied to the general population (important to have random sampling)
accuracy = how close is your data to the 'true,' 'known,' or 'standard' values (comparing your results to what 'should' have happened)
BEST OF LUCK TO EVERYONE FOR TOMORROW!!!
do you guys think we are going to have to draw a phylogenetic tree on the exam?
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md2112 monoclonal antibodies can either stimulate, supress or have no effect on the immune system. it just depends on what the antibody is targeted for.
For cancerous cells, monoclonal antibodies can be modified to carry toxins (anti-cancer drugs), so when the antibody binds to the non-self antigen on the surface of the cancerous cell, it releases the toxins which enter the infected cell and induce apoptosis, causing the cancerous cell to die. This stimulates the immune system.
For autoimmune diseases, antibodies can be targeted to block particular proteins in the pathway of the infection, e.g. with Rheumatoid arthritis, monoclonal antibodies can block a protein that causes inflammation. So blocking that protein will prevent inflammation and help alleviate symptoms of the condition. This suppresses the immune system.
I would suggest having a look at question 6 in the 2022 sample exam as it talks about this.
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chemistry1111 no one can tell what types of questions they will ask. if they do ask it will most likely be drawing 1 or 2 branches on a phylogenetic tree that is already provided, as opposed to drawing an entire tree from scratch. Have a look at question 9c from the 2020 vcaa exam if you want to get an idea of what it might look like.
do we need to know about photosystems 1 and 2 in the light dependent stage of photosynthesis? if so could someone please explain.
MCQ 10 in the 2022 vcaa exam involves it but I have never seen any other questions about it ever, nor is it specified in the study design, nor was I taught it by my tutor or at school! just seems like such a random question.
Omg yes! When I did bio last year, I went way to in depth in this. I think Douchy has a video about it somewhere…. And there was stuff on Khan Academy too…
Simply put, there are two photosystems in the membrane of chloroplasts. 1 and 2
Photosystem 2 is the important one
It is able to oxidise oxygen! Which is really hard to do. Using sunlight it splits water into O2 gas and H+ ions, and sends the electron down the transport chain - which pumps hydrogens across the membrane, making a proton gradient…
Etc… etc
bioho4
Hi
This is a bit late to ask that question especially since the bio exam has already passed.
Anyways,
VCAA does not expect you to know the details of the biochemical pathways of photosynthesis (such as photosystems). They only expect you to know the reactants, products and location of each stage of photosynthesis and and role of RuBisCO.
FYI, photosystems 1/2 split H20 in the light dependent stage of photosynthesis.
Hope this makes sense.