General Thoughts: Biology (1 Viewer)

Abbiesaurus

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what questions that pls write q and a
A patient was being treated for an infection using an antibiotic. At seven day intervals a swab was taken from the mouth and cultured in a fresh agar plate.

Day 1 plate: 1 grey:9 white
Day 8 plate: 4 grey:3 white
Day 15 plate: 7 grey:1 white

White = species 1 Grey = species 2

(A) Species 1 was a food source for Species 2 allowing more of Species 2 to grow.
(B) Species 1 and Species 2 are both fungi, but Species 1 is killed by the antibiotic while Species 2 uses the antibiotic as food.
(C) As the number of Species 2 increased, they changed the chemical conditions of the agar plate stopping the growth of Species 1.
(D) There is normally a balance between the number of each species but the removal of Species 1 by the antibiotic allowed more of Species 2 to grow.
 

sunsettah

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I actually thought it was a tricky exam.

Many multiple choice ones were really hard/ didn't make sense to me.
1. this one confused me so much, I ended up putting d. crap
2. b easy
3. b ..right?
4. a thought it was best
5. I thought none of these were right. guessed A pfft
6. put c right?
7. a right?
8. b right?
9. c right?
10. a right
11. this one also fizzed my brain. ended up putting d.
12. I ALMOST CRIED WHEN I READ THIS ONE. I knew it lowered the pH but didn't know if acid or alkali was low or high. what a waste. I picked c but it was wrong.
13. I thought this was a stupid question. i guessed b
14. b right?
15. this one was also very difficult/stupid. i guessed d.

That protozoan, fungi bacteria table I would have lost 3 marks since I knew none of them. I didn't think we had to memorise all of those.

My other problem was that I had no idea about that 'action potential' thing in communication. It wasn't in the textbook which i read like 5 times. wtf


I'm pretty crushed. Bio was the one I thought would be the easiest. I was aiming for band 6. pretty sure that's no longer possible :(
yeah i think i got about 6 or 7 for m.c. at best
 

sunsettah

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A patient was being treated for an infection using an antibiotic. At seven day intervals a swab was taken from the mouth and cultured in a fresh agar plate.

Day 1 plate: 1 grey:9 white
Day 8 plate: 4 grey:3 white
Day 15 plate: 7 grey:1 white

White = species 1 Grey = species 2

(A) Species 1 was a food source for Species 2 allowing more of Species 2 to grow.
(B) Species 1 and Species 2 are both fungi, but Species 1 is killed by the antibiotic while Species 2 uses the antibiotic as food.
(C) As the number of Species 2 increased, they changed the chemical conditions of the agar plate stopping the growth of Species 1.
(D) There is normally a balance between the number of each species but the removal of Species 1 by the antibiotic allowed more of Species 2 to grow.

I think I picked C, it seemed the most logical. What was it?
 

2AM_rendezvous

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A patient was being treated for an infection using an antibiotic. At seven day intervals a swab was taken from the mouth and cultured in a fresh agar plate.

Day 1 plate: 1 grey:9 white
Day 8 plate: 4 grey:3 white
Day 15 plate: 7 grey:1 white

White = species 1 Grey = species 2

(A) Species 1 was a food source for Species 2 allowing more of Species 2 to grow.
(B) Species 1 and Species 2 are both fungi, but Species 1 is killed by the antibiotic while Species 2 uses the antibiotic as food.
(C) As the number of Species 2 increased, they changed the chemical conditions of the agar plate stopping the growth of Species 1.
(D) There is normally a balance between the number of each species but the removal of Species 1 by the antibiotic allowed more of Species 2 to grow.

i picked B but now i think D is most logical...
 

sunsettah

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ok im feeling slightly better,... our class didnt even finish the topic, we ran out of time so quickly.


.....How did other peoples classes go time-wise, did you get through all the topics in time?

I did mine.. From one text book, just filled in the answers of the questions, n that was it.

I had 3 weeks misadventure style leave...

and i never heard of like... any of those last quesions.. except the labellijng of the eye.. and maybe the 2nd one (i dnt have a copy of the exam)
 

sb22

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Re: Hsc 2009 bio exam

I thought the exam went really really well, there was nothing that really struck me except for the carbon dioxide and oxygen inthe lungs/muscles. i didn't know whether to put b or c as carbondioxide binds to haemoglobin as is dissovled in the blood.
i think i went with c.
I got so confused because I thought oxygen didn't bind "strongly" to haemoglobin - i thought it binds loosely to haemoglobin so that it can be removed easily to be used by body cells?? I went with A... =_= don't really know why

oh well. it's one mark. still hoping for a 90+

plus, is it necessary to describe the action potential itself? I know it was 5 marks, but I just talked about the reasons why an insignificant stimuli does not generate action potential, blabbed something related to all or none principle and gave a few examples. It was actually pretty long I've perfected the art of bullshitting. :)

^ i picked D, you can't conclude A or C from the info given and antibiotics kill bacteria not fungi
 

Abbiesaurus

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i picked B but now i think D is most logical...
Yeah i picked B too. But what doesn't make sense to me about D is that it says that "there is normally a balance between the number of each species", how is this true when the agar plates never show a balance between the two species....unless we are supposed to interpret it which would be kind of stupid lol.
 

Mingiee

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Kidney question: it only asked to describe 3 regions INVOLVED in the excretion of waste... and INVOLVED is anything in the entire kidney ><
i put ureter > waste actually goes out of kidney as urine
Renal artery > blood with nitrogenous crap goes into the kidney ready to be filtered...
and Cortex > where the tubules & glomeruli are of nephron etc...

what did people write for that first hand investigation question on pathogens &insect pests in plants? ... koch's postulates or just look at it under a microscope?
 

imalda

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Re: Hsc 2009 bio exam

diagrams. wtf was with all the diagrams???? the 8 marker at the end was pretty easy. the exam itself was easy but since most people found it easy, they're gonna rip marks right, left and centre. there goes my band 6
 

Timothy.Siu

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Kidney question: it only asked to describe 3 regions INVOLVED in the excretion of waste... and INVOLVED is anything in the entire kidney ><
i put ureter > waste actually goes out of kidney as urine
Renal artery > blood with nitrogenous crap goes into the kidney ready to be filtered...
and Cortex > where the tubules & glomeruli are of nephron etc...

what did people write for that first hand investigation question on pathogens &insect pests in plants? ... koch's postulates or just look at it under a microscope?
i just put under microscope/magnifying glass.
 

Twickel

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Hey err the 8 marker, what was the wording of the question,


Since it said parents and then talked about individuals I only talked about human examples.


I explained some genetics, recessive, co dominant and heterozygous and homo and then punnet square for 1 example, then a pedigree, then talked abput PKU all hatever the mal nourishment disease is and how thats an example of cause of shit environemtn genes not expressed fully.


Was that right?
 

imalda

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Hey err the 8 marker, what was the wording of the question,


Since it said parents and then talked about individuals I only talked about human examples.


I explained some genetics, recessive, co dominant and heterozygous and homo and then punnet square for 1 example, then a pedigree, then talked abput PKU all hatever the mal nourishment disease is and how thats an example of cause of shit environemtn genes not expressed fully.


Was that right?
yeah i only used human examples since it said parents and individuals. I pretty much said something about blue eyes vs. brown eyes being genetically predetermined and the alleles that code for it with recessive, dominance etc etc.

then i went on to an example about identical twins being brought up in different environments, one nurtured, one neglected and how they would grow up looking different. one would look healthy and one malnourished and having stunted growth. i used identical twins because their genetic make up is exactly the same. i also stated this in my answer.

so basically what you had XD
 

Mysterious X

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yeah i only used human examples since it said parents and individuals. I pretty much said something about blue eyes vs. brown eyes being genetically predetermined and the alleles that code for it with recessive, dominance etc etc.

then i went on to an example about identical twins being brought up in different environments, one nurtured, one neglected and how they would grow up looking different. one would look healthy and one malnourished and having stunted growth. i used identical twins because their genetic make up is exactly the same. i also stated this in my answer.

so basically what you had XD
Yeah I talked about how meiosis can make the offspring have pretty different characteristics to the parents and then I talked about the identical twins like you :).

All in all a pretty easy exam, tripped up on some of the communication questions (the other section questions seemed so much easier, grr why couldnt the 7 marker be on cataracts -_-) but I did pretty well all in all I think.
 

2AM_rendezvous

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Yeah i picked B too. But what doesn't make sense to me about D is that it says that "there is normally a balance between the number of each species", how is this true when the agar plates never show a balance between the two species....unless we are supposed to interpret it which would be kind of stupid lol.
yeahh thats why i picked B.. haha
 

2AM_rendezvous

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yeah i only used human examples since it said parents and individuals. I pretty much said something about blue eyes vs. brown eyes being genetically predetermined and the alleles that code for it with recessive, dominance etc etc.

then i went on to an example about identical twins being brought up in different environments, one nurtured, one neglected and how they would grow up looking different. one would look healthy and one malnourished and having stunted growth. i used identical twins because their genetic make up is exactly the same. i also stated this in my answer.

so basically what you had XD

ehhhh. i used plants examples for environment daaamn =_="
 

sam5

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ehhhh. i used plants examples for environment daaamn =_="
just because it said 'parents', that doesnt stop you talking bout plants too. I used the effect of pH on flower colour.

When we hear 'parents' we think of tweo humans havin a good root, but theres nothing stopping 2 plants being parents of an offspring.
 

boxhunter91

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Guys quick question i drew a nephron :(
i didnt realise till after i drew the nephron that my answer is wrong.
You reckon i will still get marks for drawing. I labelled it all.
 

sam5

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Guys quick question i drew a nephron :(
i didnt realise till after i drew the nephron that my answer is wrong.
You reckon i will still get marks for drawing. I labelled it all.
it was 6 marks.

3 for identifying the regions (u will get 0 for this part).

3 for their functions (u may or may not get marks for this)
 

sam5

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Re: Hsc 2009 bio exam

It was definately B, why would stomates open at night when there is no light to photosynthesise with? They open early morning, close midday and open at dawn to minimise the water loss during the hottest part of the day.
(i know this is a bit late) but why would they be closed at midnight, when theres a cold temperature?

remember, plants need to open their stomates in the night to respire. Plants need oxygen to respire just like we do. Thats why theyd be open at night, so they can use all the glucose they formed (to make atp) in the day.
 

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