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sarah99 let me see if I can help!

1. Interferons have antiviral properties, so they're going to try and stop virus replication. In order for viruses to replicate, they're going to take over a host cell and its gene expression machinery, meaning interferons will pause gene expression to prevent viral proteins from being produced (aka preventing viral replication). I'm assuming it would just be preventing gene expression of viral genes, not the cell's genes. That said, the cell would probably have to be cleared from the body anyway because it's already virally infected. The interferons will just prevent the virus from spreading further.
2. No. The proteome includes all the proteins expressed in an organism. This includes MHC I, but also other proteins in the organism too.
3. Viruses and tumours/cancerous cells can downregulate the expression of MHC I markers, meaning they can be absent. Some may be present, presenting viral or tumour/cancer peptides (i.e. antigens). Some would function abnormally as well. NK cells will just look to see if normal MHC I markers are being expressed or stressed/abnormal markers, and if there's been any downregulation in the number of MHC I markers.

lune777 no problem! I'm glad it makes more sense. Year 12 photosynthesis and photorespiration stuff can get confusing.

lune777 this is probably referring more to the fact that Rubisco's affinity to bind with O2 and CO2 changes depending on the conditions, and in a sense, these two substates compete to bind to Rubisco's active site. Therefore, the two processes compete with each other. Plus, you're not just going to have one Rubisco enzyme doing all the work in the plant, but rather heaps, so at points, some may bind to O2 and some may bind to CO2. I guess some cells would be undergoing photosynthesis, whilst some may undergo photorespiration depending on the situation. It's all about relative affinity and the levels of substate present. Overall, there will be a swing towards one or the other, and in those hot/dry conditions, there are C4 and CAM plants to accommodate for its negative impacts on Rubisco (i.e. increased photorespiration). I hope that makes sense!

AngelWings okay cool. Yeah, that's why I'm interested in the unit, since I love biology but I also want to study some chemistry too! Thanks!

Hey!
So, I know this forum is usually for school stuff, but I was wondering if any Monash students have taken CHM2942 (biological chemistry)? I'm considering taking the unit next semester, although I haven't done chemistry since first year (I did enjoy it and did well, especially in second semester/CHM1022 - I meet the unit the prerequisites). I'm currently studying just biology units (immunology, dev, physiology), but this chemistry unit sounds really interesting (definitely topics I'm interested in). Even though I love biology, I kind of miss chemistry. Anyway, I'm not sure if it's going to be too hard haha or what to expect. Is this a doable unit? I'm also underloading, so I'm only taking three units per semester right now.

Any advice or thoughts would be amazing!

VitalVera haha it's not great but once it's done, you'll never have to think about it again!

Billzene haha oh my goodness SCI1000 was not it. I did it last semester and it like an absolute waste of time, but I mean at least it's all done now!

VitalVera I mean I definitely am the same in a sense that I don't study nearly as intense as year 12 (couldn't do that again, at least not long-term haha). It's a fine balance haha, one that I'm still trying to work out. I can't wait to here about how you find things over this year! Good luck!

VitalVera oooo welcome to Monash Science!!! That's super exciting congrats! I also get the whole "I have no idea" thing, since I'm in the same boat too (going into second year), and the not wanting to do medicine thing (same here haha). Your units look pretty good. I did BIO1011 and of course SCI1000. BIO1011 is pretty good. It's quite broad and covers a lot of areas within bio (has to cover the different majors across semester 1 and 2, and any other essential content), but the lecturers are generally great and it's not too hard to stay on top of. Just make sure to start your assignments early. Don't leave them last minute, since they take quite a bit of time and research (save yourself the stress). SCI1000 is really boring and kind of feels pointless haha, but its not hard as long as you do the assignments thoroughly and follow the criteria carefully (some are super pedantic and others are very vague, so make sure to clarify things where you can...oh and be really careful with the referencing since it's super easy to stuff up because it's a made-up referencing format so that people don't use referencing tools). I've heard EAE1011 is pretty good too. Anyway, enjoy o-week. Definitely a good idea doing the tours and meeting up with friends! I'm excited to see how you find first year!

DomainEducation I agree. The complex process based topics are quite hard, and I would also include the immune system in that mix too. That said, depends on what areas of biology/study/learning you find hardest.

Lemonade_222 you can use pencil but it need to be quite dark (so it will show up on the scanned copies) and not a really smudgy lead (this will ruin your other pages). Pen is always best, but I did my whole exam in pencil and was absolutely fine. Unless the rules have changed since last year, I think you'll be okay.

prettypink1881 yes you don't need to know about it in detail. From memory, VCAA usually focuses on bacteria being extracellular, but many would still initiate the cell-mediated response because they can invade host cells. In reality, biology is a lot more complex haha. However, if you were asked to explain the third line of defence in relation to bacteria, I would usually just stick with the humoral response for sake of time and the marking scheme since all bacteria will definitely initiate this response.

Taaaa76 It contains gRNA, which includes the mRNA CRISPR sequence (with viral DNA), and the endonuclease Cas9.

Taaaa76 hmm that might be why. In uni we learn that the complement system is important for many pathogens, so I have no clue why B would be correct. Since it wasn't a VCAA question, I wouldn't worry about it.

Taaaa76 oh it's about carbon dioxide ahaha. I'm currently studying haemoglobin at uni so that's why I messed that up. Yes, CO2 is carried by bicarbonate ions in plasma, but I don't think you'll need to know about that.

Taaaa76 okay yes that does make sense. Apoptosis would take place because of natural killer cells and cytotoxic T cells. My bad. You know what, it's a dumb question ahaha because complements would be released. Is this a VCAA question?

Taaaa76 okay so when a virus enters a cell, the cell will release interferons as a warning signal for other neighbouring cells. Basically, it's warning its neighbours that a virus is in the body, and therefore A wouldn't be correct. Complement proteins will be released to try and recruit more leukocytes to the site of infection, so B wouldn't be correct. Production of lymphocytes, aka T and B cells will increase as antigen-presenting cells active the humoral and cell-mediated responses, so D is also incorrect. Apoptosis however is controlled cell death. This is used by the body to get rid of body cells that are damaged, dying, potentially cancerous, etc. Cells infected by viruses undergo lysis, at least according to VCAA (biology is a lot more complicated), not controlled cell death initiated by the body itself. Therefore, I reckon C is probably correct (I might be wrong though).