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jozza80

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homijoe said:
Antibiotics are substances that destroy bacteria (bactericidal) or inhibit their growth (bacteriastatic) and hence are used to treat bacterial diseases. In recent time there has been the misuse of antibiotics such as not carrying out the full course. By not carrying out the full course acts as a selecting agent in selecting those bacetria which have a natural resistant strain to the drug. as a result the bacteria survies, reproduce and passes this resistant strain to its offsprings. Hence leading to the evolution of a colony of bacertia that are resistant to a certain antibiotic. Golden Staph is an example of an antibiotic resistant bacetria, it is resistant to methicilian. As result individuals who are infected by the Staphlycoccus Aureus pathogen are difficult to treat as it is resistant to its complementary antibiotic, methicillin. This has and continues to have a negative impact on society as it is becoming difficult to treat this bacetria, many people are dying from this disease as a result of by infected by the mulitresistant bacteria. Overall, antibiotic resistance is highly detrimental to society as bacetrial diseases are harder to treat and individuals are suffering from these multiresistant bacteria severly. Antibiotics should be carefully used and not discriminantly used to prevent the arise of more antibiotic resistant bacteria.
I don't think you can get better than that!!
 

dolbinau

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someone go over how phloem is both passive and active transport...i think ive confused myself now
Passive transport is important when describing the movement of materials in the phloem, but If it were a 1 mark question we'd only say Phloem involved active transport while Xylem involves passive IMO.

not yet, i did umat (needed for optometry) and did ok

dyu know if theyre similar?
I did UMAT! I hope they aren't similar. God. STAT is much more basic English/Maths I think, ACER have an entire practice paper for free on the STAT website so you can take a look.

Pharmacy @ uSYD is my second preference and I still need to take the STAT test too, so if anyone has taken it would be interested to know what you thought ;).
 
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bekmay

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2S1D3 said:
Excuse me if this question was asked before :D
The widespread use of antibiotics for the treatment of bacterial infections has led to the development of antibiotic resistance in some species of bacteria. From your studies of evolution and the mechanisms of inheritance, explain how resistance has been developed in bacteria.

Basically an hsc question that I did previously, found it hard but eventually got it, just want to see how you guys would answer it...
wouldn't that just be that one organism in the bacteria population had a mutation which made it resistant to the antibiotics, reproduced and the mutated gene was passed along the generations while others without the mutation didn't survive (survival of the fittest)? how many marks is this q. worth?
 
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bekmay

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"Originally Posted by homijoe
Antibiotics are substances that destroy bacteria (bactericidal) or inhibit their growth (bacteriastatic) and hence are used to treat bacterial diseases. In recent time there has been the misuse of antibiotics such as not carrying out the full course. By not carrying out the full course acts as a selecting agent in selecting those bacetria which have a natural resistant strain to the drug. as a result the bacteria survies, reproduce and passes this resistant strain to its offsprings. Hence leading to the evolution of a colony of bacertia that are resistant to a certain antibiotic. Golden Staph is an example of an antibiotic resistant bacetria, it is resistant to methicilian. As result individuals who are infected by the Staphlycoccus Aureus pathogen are difficult to treat as it is resistant to its complementary antibiotic, methicillin. This has and continues to have a negative impact on society as it is becoming difficult to treat this bacetria, many people are dying from this disease as a result of by infected by the mulitresistant bacteria. Overall, antibiotic resistance is highly detrimental to society as bacetrial diseases are harder to treat and individuals are suffering from these multiresistant bacteria severly. Antibiotics should be carefully used and not discriminantly used to prevent the arise of more antibiotic resistant bacteria."



hahah YOINK. that makes my lazy answer look so dumb. LOL.
 

sam2100

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2S1D3 said:
Excuse me if this question was asked before :D
The widespread use of antibiotics for the treatment of bacterial infections has led to the development of antibiotic resistance in some species of bacteria. From your studies of evolution and the mechanisms of inheritance, explain how resistance has been developed in bacteria.

Basically an hsc question that I did previously, found it hard but eventually got it, just want to see how you guys would answer it...

hmm depending on the amount of lines given id say something like

antibiotics are chemicals which inhibit the functioning of specific bacteria on a cellular level. widespread application of these antibiotics has resulted in large numbers of bacteria being exposed to these chemicals. due to the speed of bacterial multiplication, genetic mutations are fairly common within colonies of bacteria. thus large exposure of antibiotics to bacteria with a large number of mutations has resulted in the evolution of antibiotic resistant strains. through mechanisms of inheritance these strains survive the antibiotics and reproduce in greater numbers, causing them to become more prevelant. one such example is a strain of S. Pneumonia, the bacteria causing pneumonia which has developed antibiotic resistnace to society's two most common antibiotics (pennicilin and amphotericin). Thus large exposure to antibiotics has led to a rise of antibiotic resistant strains of bacteria
 

jozza80

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bekmay said:
wouldn't that just be that one organism in the bacteria population had a mutation which made it resistant to the antibiotics, reproduced and the mutated gene was passed along the generations while others without the mutation didn't survive (survival of the fittest)? how many marks is this q. worth?
Is it considered a mutation or just a genetic advantage?

I know a mutation can be both positive or negative to an organism, but with bacteria, its not just like one dud one gets lucky and then passes on its traits, is it? haha..
 

sam2100

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dolbinau said:
Passive transport is important when describing the movement of materials in the phloem, but If it were a 1 mark question we'd only say Phloem involved active transport while Xylem involves passive IMO.



I did UMAT! I hope they aren't similar. God. STAT is much more basic English/Maths I think, ACER have an entire practice paper for free on the STAT website so you can take a look.

Pharmacy @ uSYD is my second preference and I still need to take the STAT test too, so if anyone has taken it would be interested to know what you thought ;).
awesome thanks :D
wat u get in umat?
 

sam2100

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jozza80 said:
Is it considered a mutation or just a genetic advantage?

I know a mutation can be both positive or negative to an organism, but with bacteria, its not just like one dud one gets lucky and then passes on its traits, is it? haha..
my text uses mutation?

but yer i see where ur coming from
 

jozza80

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New question: First-hand investigation to examine plant shoots and leaves for evidence of pathogens and insect pests...

This seems to come up quite a lot!
 
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bekmay

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jozza80 said:
Is it considered a mutation or just a genetic advantage?

I know a mutation can be both positive or negative to an organism, but with bacteria, its not just like one dud one gets lucky and then passes on its traits, is it? haha..
well yeah as you said, a mutation can either be advantageous or a detriment to a species...
bacteria can become resistant in two ways,
1. mutation passed onto offspring when they divide by binary fission, or
2. horizontal evolution (exchange of genes between strains of bacteria)

so yeah, one little guy gets lucky and then passes on his genes! LOL.
 

dolbinau

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Is it considered a mutation or just a genetic advantage?

I know a mutation can be both positive or negative to an organism, but with bacteria, its not just like one dud one gets lucky and then passes on its traits, is it? haha..
I would thought it would be a mutation>Change in DNA.

New question: First-hand investigation to examine plant shoots and leaves for evidence of pathogens and insect pests...

This seems to come up quite a lot!
__________________
For this one, I usually just say collect samples from trees around local area and examine for traces of pathogens and insect pests. Black spots can indicate bacterial infection while traces of eggs/holes and/or stunted growth can indicate pests from insects e.g Aphids. I suppose risks using gloves. Is there anything more to it? (it just says 'evidence of' the pests not really anything more

awesome thanks
wat u get in umat?
Not good enough! IIRC my combined score was like 158 or something? it was 67% percentile so I was still satisfied I performed better than most people (who I assumed would be the higher performers in the state), but unless I get a UAI of 99 or 100 I have no chance for Medicine. So JCU (no UMAT) and UNSW are my only hopes :p.
 

2S1D3

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bekmay said:
wouldn't that just be that one organism in the bacteria population had a mutation which made it resistant to the antibiotics, reproduced and the mutated gene was passed along the generations while others without the mutation didn't survive (survival of the fittest)? how many marks is this q. worth?
umm like 3 marks so i think you would probably have to go with natural selection, but i dont know if you have to go in depth :S EDIT: they only gave five lines...
 

Takuto

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doesnt bacteria just split?

that one guy can go a long way if *hes* the only one left when all the other bacteria are dead from antiobiotics (lol no competition)
 

dolbinau

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For those doing communication. Can you outline the structure of the larynx? How much do we need to know for this?
 

2S1D3

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dolbinau said:
For those doing communication. Can you outline the structure of the larynx? How much do we need to know for this?
Lets see if i can remember it :)
-Human larynx is a holloow structure with the vocal chords stretched across the tube.
-It consists of nine cartilages, membranes, ligaments and a mucous lining.
-When air passes over the diaphragm, the vocal chords increase in tension to increase the pitch of the loudness.
feel free to add whatever you want, just got that from my notes
 

jozza80

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dolbinau said:
Not good enough! IIRC my combined score was like 158 or something? it was 67% percentile so I was still satisfied I performed better than most people (who I assumed would be the higher performers in the state), but unless I get a UAI of 99 or 100 I have no chance for Medicine. So JCU (no UMAT) and UNSW are my only hopes :p.
Thank you all for clarification! One of those little things I'm sure markers dont really car about anyway..

As for ^ you should just wish for a gnarley rurality - it pretty much saves you everytime!!

:D
 

Undermyskin

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From the text book, not much but from past paper, a lot.

Larynx is located at the beginning of the trachea, after the pharynx; in front of the 4th, 5th and 6th cervical vertebrae and suspended from the hyoid bone

It's a tube-shaped structure comprised of a complex system of muscles, cartilages and connective tissues

Its framework includes 3 unpaired and 3 paired cartilages that create a passageway

The vocal cords, made up of elastic fibres, are connected to some of these (cartilages) and stretched over the tracheal opening. Along the the larynx, they surround a narrow opening called glottis.
 

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