HSC Biology Question Thread

[vox nihili]

It's an oversimplification we are supposed to know what Addison's disease actually is but some people simplify it to mean there is no aldosterone

Thanks

So there you go everyone: Addison's is an adrenal insufficiency, it also involves cortisol!

Loss of aldosterone alone is called Conn syndrome

[amina_98]

 I came across this question in 2013 paper from genetics section  "analyse how the understanding of mechanisms of genetic change has influenced the use of genetic technology in society"
Right so a couple of marks in the marking guidelines are allocated for "relates understanding of genetic change to the use of genetic technology"
Could someone shed some light here I got stuck there in terms of formulating my "knowledge" to respond to what they're asking
cheers

[aimbotted]

If anyone is doing the Genetics option can you go through a quick summary of what this dotpoint is?
Identify the role of genes in embryonic development
i can't really understand it besides the fact that there are structural and regulating genes.

[studybuddy7777]

Hey aimbotted,
I personally didnt do genetics (did communication instead) but a quick google turned this up:

Homeotic gene, any of a group of genes that control the pattern of body formation during early embryonic development of organisms. These genes encode proteins called transcription factors that direct cells to form various parts of the body.

For example, in fruit flies (Drosophila), mutation of a particular homeotic gene results in altered transcription, leading to the growth of legs on the head instead of antenna; this is known as the antennapedia mutation.

(Source: Britannica)

Hope this helps and sorry I couldnt do more for you!

[studybuddy7777]

I came across this question in 2013 paper from genetics section  "analyse how the understanding of mechanisms of genetic change has influenced the use of genetic technology in society"
Right so a couple of marks in the marking guidelines are allocated for "relates understanding of genetic change to the use of genetic technology"
Could someone shed some light here I got stuck there in terms of formulating my "knowledge" to respond to what they're asking
cheers

Not that I have done genetics (maybe aimbotted could help?) but this is how i would structure it (assuming 7 or 8 marks)

First, topic sentence. This is basically rewording the question (not always needed but imho i think dump statements are good)

Next, What are the mechanisms of genetic change? What causes a change in the genes?

Then bring in your genetic technology. Define GT1. Then say GT1 has influenced society by... (Advances in technology yada yada yada)

This has led to.. (Increased/decreased genetic diversity and changes to genes and gene technology)

Wouldnt hurt to talk about ethical issues either

Sorry I could not help more, but hopefully you (or someone else) can fill the gaps of knowledge where mine is so evidently lacking.

[Blissfulmelodii]

hey, I was hoping someone could explain to me how to go about answering this question. Essentially how to structure the response and what details are exactly needed to satisfactorily answer it? 

"Scientists have tried to achieve a viable embryo by fusing two ova (eggs) from the same female.
Explain whether the offspring produced using this process would be a clone of the female whose two ova were used. Use your knowledge of gamete formation and sexual reproduction to support your answer."

Also I am pretty hopeless at the Kidney stuff so I would greatly appreciate if someone could explain the role of the kidney in the excretory system of fish and mammals and how it all works in simple terms?

Thank you in advanced!! 

[marynguyen18]

i was looking at the 2004 HSC question and was unsure on how to answer q24. "JUSTIFY CONTINUED RESEARCH INTO THE DEVELOPMENT OF ARTIFICIAL BLOOD." Can anyone please explain to me what exactly is artificial blood and how it can be incorporated into this kind of question. I looked at the answers and didn't like the way it was explained.

Thank you in advanced

[aimbotted]

i was looking at the 2004 HSC question and was unsure on how to answer q24. "JUSTIFY CONTINUED RESEARCH INTO THE DEVELOPMENT OF ARTIFICIAL BLOOD." Can anyone please explain to me what exactly is artificial blood and how it can be incorporated into this kind of question. I looked at the answers and didn't like the way it was explained.

Thank you in advanced

artificial blood is blood that is created, not donated. it is important to develop artificial blood as sometimes donated blood may not be readily available, as opposed to where you can create blood in a laboratory there will always be a constant supply of blood. another reasoning for artificial blood is that it does not require cross matching for the type of blood, this will remove the necessity of finding the correct type of blood in situations such as transfusions basically saving lives.

there are more dotpoints but this is just what i could think of from the top of my head (god help me if i'm totally wrong)

you can further elaborate on those points as to how it saves lives and is more effective than relying on donated blood.

[aimbotted]

I came across this question in 2013 paper from genetics section  "analyse how the understanding of mechanisms of genetic change has influenced the use of genetic technology in society"
Right so a couple of marks in the marking guidelines are allocated for "relates understanding of genetic change to the use of genetic technology"
Could someone shed some light here I got stuck there in terms of formulating my "knowledge" to respond to what they're asking
cheers

i'm not entirely sure if i'm answering this question correct but i'll give it a go

what i think the question is asking for is the mechanics of genetic change and how we use those mechanisms in society

the mechanics of genetic change are technologies such as recombinant dna (snipping dna and inserting into another organism) and selective breeding. i think both are mechanisms to change the genetic composition in an organism.

we use technologies such as recombinant DNA in society to create necessary proteins such as insulin to treat diabetes in humans, effectively helping to treat or cure a disease. another use of a mechanism of genetic change is selective breeding in which we choose organisms with desirable traits and  breed them for their benefits, such as higher yields better quality better suitability

benefits of these technologies involve having the ability to treat a disease, another benefit is having the ability to solve world issues such as world hunger (transgenic species)

disadvantages of this technology include ethical issues and which you are disrupting nature and evolution

[Ayyddaan]

i was looking at the 2004 HSC question and was unsure on how to answer q24. "JUSTIFY CONTINUED RESEARCH INTO THE DEVELOPMENT OF ARTIFICIAL BLOOD." Can anyone please explain to me what exactly is artificial blood and how it can be incorporated into this kind of question. I looked at the answers and didn't like the way it was explained.

Thank you in advanced

So artificial blood is an alternative for actual blood, that is 'man-made'; it carries out some of the functions of real blood. Hemerythrin is an example of artificial blood - it is a protein extracted from sea worms and mixed with water & salt; could lead to 'instant blood' as it is like a 'just add water' thing.
So, now that you know what Artificial Blood is, you need to know why it is good (in order to justify the continued research into the development of it). Artificial blood has heaps of benefits:
- It can be sterilised. Therefore, it can prevent the spread of diseases like HIV - if you sterilise biological blood, it will kill the cells.
- AB doesn't have a membrane, therefore there is no need for cross matching - 'universal blood type'.
- Shelf-life of up to 3 years, unlike biological blood which can only be stored for a few weeks.
- Since it does not contain other human cells, it is safe for use by religious groups that cannot use biological blood due to beliefs.
- Does not cause any side-effects

Now, why do we need to conduct more research?
- the population is rising, but not enough people are donating - more blood is needed!
- Useful in emergencies - no time to test for blood type.

Therefore, to answer this question, you need to, using this information, support the idea of continuing research in AB.

[Skidous]

I did a little report upload of artificial blood If you want a look it's on this thread

[marynguyen18]

can anyone explain chromosomes to me i always get confused with it

[Lottie99]

Gene homologues and gene cascades. Why. Just why.
I really struggle with those 7 or 8 mark questions at the end of the code broken that have vague mentions of technology and genetics and genetic change and development. What kind of things are really core to understanding gene homologues and gene cascades and how they fit within all those 8 mark questions?

[:3]

hey, I was hoping someone could explain to me how to go about answering this question. Essentially how to structure the response and what details are exactly needed to satisfactorily answer it? 

"Scientists have tried to achieve a viable embryo by fusing two ova (eggs) from the same female.
Explain whether the offspring produced using this process would be a clone of the female whose two ova were used. Use your knowledge of gamete formation and sexual reproduction to support your answer."

Also I am pretty hopeless at the Kidney stuff so I would greatly appreciate if someone could explain the role of the kidney in the excretory system of fish and mammals and how it all works in simple terms?

Thank you in advanced!! 

First question: the answer is basically that it does not produce a clone of the female whose ovaries were combined.
- Refer to Boveri's experiment with sea urchins: he discovered that if only the nucleus of one parent was present, it would result in abnormalities (not 100% sure why but probably due to chromosomes not being transferred properly).
- Refer to how crossing over, independent assortment and random segregation during meisos results in a different and unique genetic makeup to that of the parent cell within each daughter cell produced.

Second question:
- the kidney is fundamentally involved in homeostasis; it removes excess substances and nitrogenous waste that is either not needed by or toxic to the body, or reabsorps substances needed by the body for optimal functiong (e.g. salt and water).
- For how it works, are there any specific areas/concepts you are unsure about? The process itself can't be simplified other than the fact that blood enters it, reabsorption occurs throughout and the left over bits are excreted as urine.

Hopefully this helps .

[Lottie99]

can anyone explain chromosomes to me i always get confused with it

Chromosomes as in do they exist? Or their function? Or how they came about? Or their structure? Or our understanding?