VCE Biology Question Thread

[Jackie Chan]

Thanks PheonixxFire

Also , can someone pls outline the general steps of antibiotic resistance in bacteria?

- resistance to the particular antibiotic already exists in the population (some bacteria will be resistant whilst others will be sensitive)
- the use of antibiotics causes the death of all the sensitive bacteria
- the resistant bacteria survive long enough to reproduce and pass down this resistance to the next generation
- over time, as resistance to the antibiotic has a high adaptive value (meaning it is advantageous), the number of bacteria that are resistant to the antibiotic will increase

 

[dimenc]

Hi Guys
I saw a post earlier stating that we need to know all the dates for when organism arose etc.
Does anyone have these dates and the eras they occured?
I cannot find one reliable source everywhere and it is so annoying!
Chloe

[dimenc]

Hi Guys
I saw a post earlier stating that we need to know all the dates for when organism arose etc.
Does anyone have these dates and the eras they occured?
I cannot find one reliable source everywhere and it is so annoying!
Chloe

[Jackie Chan]

Hi Guys
I saw a post earlier stating that we need to know all the dates for when organism arose etc.
Does anyone have these dates and the eras they occured?
I cannot find one reliable source everywhere and it is so annoying!
Chloe

Check out PhoenixxFire's resource 
https://atarnotes.com/forum/index.php?topic=174693.0

[zenith101]

hey everyone,

is there a list of specific hominin/hominids/primates we are supposed to know- such as dates of evolution and sets of detailed characteristics?

Or do you think knowing the order of the hominins and general trends of characteristics is sufficient information?

Thanks

[PhoenixxFire]

Thanks PheonixxFire

Also , can someone pls outline the general steps of antibiotic resistance in bacteria?

To add to what annieml said, antibiotic resistance genes can be found in plasmids. Plasmids can move between closely related bacteria (ie same genus). This means that organisms that were not resistant can become resistant due to taking up plasmids. Not entirely sure how much about this we need to know but there's was a multiple choice question on it (which could be answered by elimination alone) in a 2017 NEAP test.

[rainbowsparkles15]

hey everyone,

is there a list of specific hominin/hominids/primates we are supposed to know- such as dates of evolution and sets of detailed characteristics?

Or do you think knowing the order of the hominins and general trends of characteristics is sufficient information?

Thanks

My teacher has suggested that we should be familiar with the order of hominins and some basic details about the main ones but we haven't learnt any particular hominoids or primates (she could be wrong!)

I would place a greater emphasis on the general trends and characteristics as this seems to be what the study design is focused on

Good luck for Friday!

[rainbowsparkles15]

Hey guys,

If anyone could explain multiple choice 5 and 28 to me from the Northern Hemisphere exam it would be greatly appreciated

http://www.vcaa.vic.edu.au/Pages/vce/nht/resources.aspx

[vox nihili]

My teacher has suggested that we should be familiar with the order of hominins and some basic details about the main ones but we haven't learnt any particular hominoids or primates (she could be wrong!)

I would place a greater emphasis on the general trends and characteristics as this seems to be what the study design is focused on

Good luck for Friday!

Agreed. The emphasis on the general trends in the study design is likely a reaction to the fact that the study design used to be quite ambiguous about what you needed to know, leading some students to attempt to remember every part of the family tree. They've also added mentions in about what happens when we discover a new species, which actually happened twice during my study design and that, once again, led to some trouble.

[vox nihili]

Hey guys,

If anyone could explain multiple choice 5 and 28 to me from the Northern Hemisphere exam it would be greatly appreciated

http://www.vcaa.vic.edu.au/Pages/vce/nht/resources.aspx

Didn't even know this existed, wow.

5: A: nope because we can see that it survives best when oxygen isn't around
B: The opposite is true; they flourish in high oxygen.
C: growth appears unaffected by oxygen levels, suggesting they both survive well in oxygen and without oxygen around...implies they can do both anaerobic and aerobic respiration.
D: This is the hard one. They can grow without any oxygen at all, so definitely anaerobic. But growth increases with oxygen levels, suggesting they can do aerobic (hence the increase).

Don't like this question. I don't think there's enough information to say C with any confidence (it could just all be anaerobic), but it's clearly the best answer

Question 28

Again, not a fantastic question to be honest.

The answer is high concentrations of tryptophan. Think about how the system should be designed. The trp repressor prevents the cell from producing tryptophan. When would you want to do that? When the cell already has lots of tryptophan and thus doesn't need to make any.

[zenith101]

Agreed. The emphasis on the general trends in the study design is likely a reaction to the fact that the study design used to be quite ambiguous about what you needed to know, leading some students to attempt to remember every part of the family tree. They've also added mentions in about what happens when we discover a new species, which actually happened twice during my study design and that, once again, led to some trouble.

Thanks a lot. One point i found confusing was the homo denisovans, considering scientists are still debating over its classification, and the relatedness between denisovan, neanderthals and sapiens is still under investigation.

[vox nihili]

Thanks a lot. One point i found confusing was the homo denisovans, considering scientists are still debating over its classification, and the relatedness between denisovan, neanderthals and sapiens is still under investigation.

That’s exactly right. They’ve specifically referenced them in the study design.
Notably absent are H.floresiensis, which are even more controversial.

[Seno72]

Hey lads. Do we need to know what the vascular and cellular stages of inflammation response? It does not state in the study design but it's on the Jacaranda Bio book (pg. 303)

[Jackie Chan]

Hey lads. Do we need to know what the vascular and cellular stages of inflammation response? It does not state in the study design but it's on the Jacaranda Bio book (pg. 303)

If it's not on the study design, they can't test us on it unless they provide enough extra information that we can use to answer a particular question. However, it is specified on the study design that you do know the steps in the inflammatory response:

1. Bacteria or a pathogen breaches the first line of defence e.g. through an open wound.
2. Injured cells release cytokines which attract mast cells and neutrophils. Mast cells release histamine which increases the permeability of the blood vessels, allowing complement proteins and leukocytes to easily enter the site of infection.
3. Neutrophils migrate towards the cytokines, become activated and secrete defensins and hydrogen peroxide at the site of infection to kill the pathogens and they also recruit macrophages.
4. These macrophages phagocytose the debris and pathogen at the site of infection.
5. The inflammatory response continues until the wound is healed and the pathogen is removed.

[Seno72]

Cheers

If it's not on the study design, they can't test us on it unless they provide enough extra information that we can use to answer a particular question. However, it is specified on the study design that you do know the steps in the inflammatory response:

1. Bacteria or a pathogen breaches the first line of defence e.g. through an open wound.
2. Injured cells release cytokines which attract mast cells and neutrophils. Mast cells release histamine which increases the permeability of the blood vessels, allowing complement proteins and leukocytes to easily enter the site of infection.
3. Neutrophils migrate towards the cytokines, become activated and secrete defensins and hydrogen peroxide at the site of infection to kill the pathogens and they also recruit macrophages.
4. These macrophages phagocytose the debris and pathogen at the site of infection.
5. The inflammatory response continues until the wound is healed and the pathogen is removed.

Thanks for the reply. Also how does swelling occur in the inflammation response? Is it because of the restricted blood flow from the source of infection?