ATAR Notes: Forum
VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Biology => Topic started by: VCAA Official on October 19, 2010, 07:32:49 pm
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Q) Which species, neanderthls or homosapiens is better adaptied to the cold. explain your answer
my answer) Our knowledge of the past tells us that sapiens outcompeted neanderthals and the temperature was not a significant factor in either of hte species overall survival. Their adaptation to the cold is thus equally good and equal in that they were suitably adapted to cold conditions such that it did not hinder their species's survival and both species overcame this selection factot
the examiner: neanderthals are better adapted to the cold since they hae a smaller surgface to volume ratio being short and stocky
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is the author of the STAV exam retarded?
furthermore, I doubt I would get this mark even if it was a VCAA exam
fucking stupid vce - i feel so arrogant in thinking that i'm just too smart for it and that is the reason for how badly i'm doing in it
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Q) Which species, neanderthls or homosapiens is better adaptied to the cold. explain your answer
my answer) Our knowledge of the past tells us that sapiens outcompeted neanderthals and the temperature was not a significant factor in either of hte species overall survival. Their adaptation to the cold is thus equally good and equal in that they were suitably adapted to cold conditions such that it did not hinder their species's survival and both species overcame this selection factot
the examiner: neanderthals are better adapted to the cold since they hae a smaller surgface to volume ratio being short and stocky
---
is the author of the STAV exam retarded?
furthermore, I doubt I would get this mark even if it was a VCAA exam
fucking stupid vce - i feel so arrogant in thinking that i'm just too smart for it and that is the reason for how badly i'm doing in it
well, you shouldn't have to know something like this, but the writer was correct, neanderthals were also more hairy and had a greater proportion of fat, which would have helped retain heat.
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Q) Which species, neanderthls or homosapiens is better adaptied to the cold. explain your answer
my answer) Our knowledge of the past tells us that sapiens outcompeted neanderthals and the temperature was not a significant factor in either of hte species overall survival. Their adaptation to the cold is thus equally good and equal in that they were suitably adapted to cold conditions such that it did not hinder their species's survival and both species overcame this selection factot
the examiner: neanderthals are better adapted to the cold since they hae a smaller surgface to volume ratio being short and stocky
---
is the author of the STAV exam retarded?
furthermore, I doubt I would get this mark even if it was a VCAA exam
fucking stupid vce - i feel so arrogant in thinking that i'm just too smart for it and that is the reason for how badly i'm doing in it
well, you shouldn't have to know something like this, but the writer was correct, neanderthals were also more hairy and had a greater proportion of fat, which would have helped retain heat.
Yes, while I can understand why you might believe that (you're wrong), the question asked for 'better adapted'. If neanderthals were still alive we could SPECULATE that this, which theoretical would benefit them, might be a 'better adaptation', but the fact of the matter is that adaptations are so successful as they help an species to surive. Because of fossil evidence and such, we do not have to make such meaningless speculations because we know for a fact that sapiens survived over neanderthals. hence, we can't draw the examiners conclusion (or yours)
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Because of fossil evidence and such, we do not have to make such meaningless speculations because we know for a fact that sapiens survived over neanderthals.
And the temperature was the only factor that contributed to their relative fitnesses? A surviving species is not better adapted in all respects when compared to an extinct species. Hell, a surviving species may be worse adapted than an extinct species depending on the specific circumstances. The answer provided is perfectly reasonable. A smaller body has a lower surface area to volume ratio (also, probably a lower metabolism) which aids thermoregulation.
The entire question is speculation, the fact that one species is extinct is irrelevant to the specific, hypothetical situation. If it had asked about the general fitness of the two species, then your conclusion would be correct. But it's entirely possible for a fitter organism to lack certain adaptations that are beneficial in less fit organisms (eg bacterial cell walls).
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well, some people argue that neanderthals became extinct because of the changing environmental conditions (for example end of an ice age), or from competition with homo sapiens.
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Q) Which species, neanderthls or homosapiens is better adaptied to the cold. explain your answer
my answer) Our knowledge of the past tells us that sapiens outcompeted neanderthals and the temperature was not a significant factor in either of hte species overall survival. Their adaptation to the cold is thus equally good and equal in that they were suitably adapted to cold conditions such that it did not hinder their species's survival and both species overcame this selection factot
the examiner: neanderthals are better adapted to the cold since they hae a smaller surgface to volume ratio being short and stocky
---
is the author of the STAV exam retarded?
furthermore, I doubt I would get this mark even if it was a VCAA exam
fucking stupid vce - i feel so arrogant in thinking that i'm just too smart for it and that is the reason for how badly i'm doing in it
well, you shouldn't have to know something like this, but the writer was correct, neanderthals were also more hairy and had a greater proportion of fat, which would have helped retain heat.
Yes, while I can understand why you might believe that (you're wrong), the question asked for 'better adapted'. If neanderthals were still alive we could SPECULATE that this, which theoretical would benefit them, might be a 'better adaptation', but the fact of the matter is that adaptations are so successful as they help an species to surive. Because of fossil evidence and such, we do not have to make such meaningless speculations because we know for a fact that sapiens survived over neanderthals. hence, we can't draw the examiners conclusion (or yours)Because of fossil evidence and such, we do not have to make such meaningless speculations because we know for a fact that sapiens survived over neanderthals.
And the temperature was the only factor that contributed to their relative fitnesses? A surviving species is not better adapted in all respects when compared to an extinct species. Hell, a surviving species may be worse adapted than an extinct species depending on the specific circumstances. The answer provided is perfectly reasonable. A smaller body has a lower surface area to volume ratio (also, probably a lower metabolism) which aids thermoregulation.
The entire question is speculation, the fact that one species is extinct is irrelevant to the specific, hypothetical situation. If it had asked about the general fitness of the two species, then your conclusion would be correct. But it's entirely possible for a fitter organism to lack certain adaptations that are beneficial in less fit organisms (eg bacterial cell walls).
No you have misunderstood my answer, please re-read it.
I'm not saying sapiens are better adapted. I'm saying you cannot conclude either way, consistent with what you're rhetorically implying.
Also: "urviving species may be worse adapted than an extinct species depending on the specific circumstances." Only when chance comes into play (genetic drift, etc).Which, as I said earlier. is not what our fossil record and the evidence at hand suggests.
And just as a side note: "The entire question is speculation, the fact that one species is extinct is irrelevant to the specific, hypothetical situation. If it had asked about the general fitness of the two species, then your conclusion would be correct. But it's entirely possible for a fitter organism to lack certain adaptations that are beneficial in less fit organisms (eg bacterial cell walls)."
Do you even know what science is? This paragraph is an embarrassment to your intelligence.
well, some people argue that neanderthals became extinct because of the changing environmental conditions (for example end of an ice age), or from competition with homo sapiens.
If that is so then I am wrong and you are right. My understand is, however, that the broad scientific concensus is that outcompetition was the primary factor behind neanderthal extinction rather than changing environmental conditions. If I am wrong (I doubt it, since I've researched this), then your conjecture is correct. In summary, no you're wrong.
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And what exactly do you think is wrong with my paragraph and my grasp of science?
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why are you being so agressive with your opinion?
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Feels like VCAA official's interpretation of what adaptation means differs to everyone else's. I don't see how it's flawed to say that someone can have a negative adaptation and still be fitter overall. There's plenty of adaptations and obviously each organism wins and loses somewhere; but what ultimately decides fitness is the extent of these disadvantages relative to the selection pressure provided by the environment. I guess you could say that fitness is determined by the adaptation that is being stressed the most at that time, and in retrospect, could be seen in terms of whatever selection pressure ultimately led to extinction.
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i sense a VCAA official is uncomfortable and in an effort to impose authority they are trying to 'speak down' to us... tut tut tut
if the theory provided by a VN member is correct, why fix what isn't broken?
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tut tut tut. ;D
anyways, since this is a bio thread, imma a bit confused about the circulatory system in animals and how it works. Can someone try explaining/summarizing the circulatory system in a succinct manner for me and also about valves and where deoxygenated and oxygenated blood comes from/goes to (and do a better job than my teacher :))
thanks!
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Feels like VCAA official's interpretation of what adaptation means differs to everyone else's. I don't see how it's flawed to say that someone can have a negative adaptation and still be fitter overall. There's plenty of adaptations and obviously each organism wins and loses somewhere; but what ultimately decides fitness is the extent of these disadvantages relative to the selection pressure provided by the environment. I guess you could say that fitness is determined by the adaptation that is being stressed the most at that time, and in retrospect, could be seen in terms of whatever selection pressure ultimately led to extinction.
thank you
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It was a shit paper in my opinion. The MC Q on non-disjunction was good but the short answer for AOS2 was so bad.
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tut tut tut. ;D
anyways, since this is a bio thread, imma a bit confused about the circulatory system in animals and how it works. Can someone try explaining/summarizing the circulatory system in a succinct manner for me and also about valves and where deoxygenated and oxygenated blood comes from/goes to (and do a better job than my teacher :))
thanks!
haha, I'm no expert, but here's me trying:
so the heart pumps deoxygenated blood to the lungs,where oxygen binds to the haemoglobin on the red blood cells, this now oxygenated blood travels back to the heart and is pumped throughout the body and the oxygen is transported into the cells where it is used for processes such as cellular respiration. I do realise that was a long sentence and I apologize :)
okay and the valves are present to prevent blood from flowing backwards in the reverse direction.
so how was that. Btw are you a year 12?
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tut tut tut. ;D
anyways, since this is a bio thread, imma a bit confused about the circulatory system in animals and how it works. Can someone try explaining/summarizing the circulatory system in a succinct manner for me and also about valves and where deoxygenated and oxygenated blood comes from/goes to (and do a better job than my teacher :))
thanks!
haha, I'm no expert, but here's me trying:
so the heart pumps deoxygenated blood to the lungs,where oxygen binds to the haemoglobin on the red blood cells, this now oxygenated blood travels back to the heart and is pumped throughout the body and the oxygen is transported into the cells where it is used for processess such as cellular respiration. I do realise that was a long sentence and I apologize :)
okay and the valves are present to prevent blood from flowing backwards in the reverse direction.
so how was that. Btw are you a year 12?
It should be year 11 bio
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And what exactly do you think is wrong with my paragraph and my grasp of science?
I lol'd for like two minutes - you are the best scientist I know (IN CYBERSPACE).
Also, WHAT THE HELL DUDE, YOU DON'T MAKE THE RULES, THE EXAMINER DOES AND IN THIS CASE THE ASSESSOR SAID SURFACE TO VOLUME RATIO SO ROLE WITH IT.
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Oh my god I just spelled 'roll' as 'role'. I am pro at all things academic.
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And what exactly do you think is wrong with my paragraph and my grasp of science?
I lol'd for like two minutes - you are the best scientist I know (IN CYBERSPACE).
Also, WHAT THE HELL DUDE, YOU DON'T MAKE THE RULES, THE EXAMINER DOES AND IN THIS CASE THE ASSESSOR SAID SURFACE TO VOLUME RATIO SO ROLE WITH IT.
but come on he has a point, i mean surface area might be relevant to unit 3 biology but not this semester. im sure any answer that is justified with an appropriate explanation would suffice for the mark
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And what exactly do you think is wrong with my paragraph and my grasp of science?
I lol'd for like two minutes - you are the best scientist I know (IN CYBERSPACE).
Also, WHAT THE HELL DUDE, YOU DON'T MAKE THE RULES, THE EXAMINER DOES AND IN THIS CASE THE ASSESSOR SAID SURFACE TO VOLUME RATIO SO ROLE WITH IT.
but come on he has a point, i mean surface area might be relevant to unit 3 biology but not this semester. im sure any answer that is justified with an appropriate explanation would suffice for the mark
yeah but this was from a prac exam, so it's not as if this would be part the vcaa exam.
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tut tut tut. ;D
anyways, since this is a bio thread, imma a bit confused about the circulatory system in animals and how it works. Can someone try explaining/summarizing the circulatory system in a succinct manner for me and also about valves and where deoxygenated and oxygenated blood comes from/goes to (and do a better job than my teacher :))
thanks!
haha, I'm no expert, but here's me trying:
so the heart pumps deoxygenated blood to the lungs,where oxygen binds to the haemoglobin on the red blood cells, this now oxygenated blood travels back to the heart and is pumped throughout the body and the oxygen is transported into the cells where it is used for processes such as cellular respiration. I do realise that was a long sentence and I apologize :)
okay and the valves are present to prevent blood from flowing backwards in the reverse direction.
so how was that. Btw are you a year 12?
To elaborate, just be aware that there's two circuits. Some basic definitions first though. Arteries pump blood away from the heart. Arteries then lead to capillaries where gas exchange occurs. Veins are what bring the blood back towards the heart.
So basically yeh, there's two systems; the systemic system which pumps oxygenated blood towards capillaries at the tissues to supply the tissues with oxygen (i.e. oxygen diffuses from the blood to the tissue), and the pulmonary system which pumps deoxygenated blood towards the capillaries in the lungs to reoxygenate the blood (i.e. oxygen diffuses from the air in the lungs into the blood). So these two circuits basically form a figure-eight: oxygenated blood gets pumped from the heart to the tissues via systemic arteries, supplies the tissues, drains back as deoxygenated blood into the heart via systemic veins, gets pumped from the heart into the pulmonary arteries into the lungs, picks up oxygen in the lungs and drains back via the pulmonary veins and we're back where we started. Draw it out and you'll get a better idea I guess. So yeh, be aware that the commonly believed 'arteries=oxygenated, veins=deoxygenated blood' thing doesn't actually work. It's flipped in the pulmonary system as you can see.
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This thread is so active! More than one answer is likely to be accepted here but that doesn't mean the STAV response is incorrect or irrelevant.
You are expected to retain knowledge of surface area from unit 3 because it was also studied in units 1 and 2, and is therefore testable on your exam.
It's like expecting not to be tested on addition when you walk into methods 3/4 exams.
Basic knowledge which is to be reapplied again and again.
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haha, I'm no expert, but here's me trying:
so the heart pumps deoxygenated blood to the lungs,where oxygen binds to the haemoglobin on the red blood cells, this now oxygenated blood travels back to the heart and is pumped throughout the body and the oxygen is transported into the cells where it is used for processes such as cellular respiration. I do realise that was a long sentence and I apologize :)
okay and the valves are present to prevent blood from flowing backwards in the reverse direction.
so how was that. Btw are you a year 12?
To elaborate, just be aware that there's two circuits. Some basic definitions first though. Arteries pump blood away from the heart. Arteries then lead to capillaries where gas exchange occurs. Veins are what bring the blood back towards the heart.
So basically yeh, there's two systems; the systemic system which pumps oxygenated blood towards capillaries at the tissues to supply the tissues with oxygen (i.e. oxygen diffuses from the blood to the tissue), and the pulmonary system which pumps deoxygenated blood towards the capillaries in the lungs to reoxygenate the blood (i.e. oxygen diffuses from the air in the lungs into the blood). So these two circuits basically form a figure-eight: oxygenated blood gets pumped from the heart to the tissues via systemic arteries, supplies the tissues, drains back as deoxygenated blood into the heart via systemic veins, gets pumped from the heart into the pulmonary arteries into the lungs, picks up oxygen in the lungs and drains back via the pulmonary veins and we're back where we started. Draw it out and you'll get a better idea I guess. So yeh, be aware that the commonly believed 'arteries=oxygenated, veins=deoxygenated blood' thing doesn't actually work. It's flipped in the pulmonary system as you can see.
:O wow that was such a good explanation!!!!!! Totally makes sense now :) you summarized the whole thing into just a paragraph compared to the 10000000000 word uber duba confusing passage from my bio txtbook.
thanks thanks thanks thanks thanks thanks!
sillysmile im yr 10 doing 1/2 bio. i wants a 49 like shinny next year but my SS will probably end up being around 49 -10 = 39 XD
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There'll be the obligatory MCQ with "the pulmonary artery carries oxygenated blood from the lungs to the heart" option to trick you :P
The cardiovascular system is pretty awesome.
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There'll be the obligatory MCQ with "the pulmonary artery carries oxygenated blood from the lungs to the heart" option to trick you :P
The cardiovascular system is pretty awesome.
Yep, definitely favourite system of the body so far. Has a bit of everything really; physiology, biochemistry, anatomy and even physics/maths!
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I'm biased towards endocrine, but otherwise CVS is my favourite.
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I'm biased towards endocrine, but otherwise CVS is my favourite.
Ahhhh, endocrine cancers are so much fun as well. Big dilemma when it comes to specialising. Hmm.
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There'll be the obligatory MCQ with "the pulmonary artery carries oxygenated blood from the lungs to the heart" option to trick you :P
The cardiovascular system is pretty awesome.
hmmm. wats the answer to that?
is it an absolute no, cause pulmonary arteries predominately carry deoxygenated blood from the heart to the lungs?
or does it do both :/
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Does doing checkpoints for bio help or would it be a waste of time.
I gots a question. This time on the digestive system:
The major function of the large intestine is to absorb water. If you were suffering from diarrhoea you would absorb 10 mL of water over 4 hours. If you were suffering from constipation you would absorb 100 mL over 4 hrs. Explain these results. Predict the amount of water you would absorb over 4 hrs if you were not suffering either disease.
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Well Checkpoints is filled with VCAA questions so it wouldn't be a waste of time but only do the questions if you have already taken the VCAA exams under exam conditions, because you will spoil them if you do Checkpoints first.
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is it an absolute no, cause pulmonary arteries predominately carry deoxygenated blood from the heart to the lungs?
or does it do both :/
Yes, it only carries deoxygenated blood to the lungs (except in utero but that doesn't really count)
The major function of the large intestine is to absorb water. If you were suffering from diarrhoea you would absorb 10 mL of water over 4 hours. If you were suffering from constipation you would absorb 100 mL over 4 hrs. Explain these results. Predict the amount of water you would absorb over 4 hrs if you were not suffering either disease.
If you absorb minimal water (10ml/4hours) then there's a lot of water left in the GIT and it has to be removed from the body somehow (ie diarrhoea).
If you absorb too much water (100ml/4hours) then there's not enough water in the GIT. This causes the faeces to move slowly through the colon/get compacted.
If you weren't suffering either disease...you'd absorb somewhere between those two values. Perhaps 55ml/4hours
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Ok, so basically
Arteries:(always heart to body)
pulmonary - carries deoxygenated blood from heart to lungs
systemic- carries oxygenated blood from heart to cells
Veins:(body to heart)
pulmonary-carries oxygenated blood from lungs to heart
systemic- carries deoxygenated blood from cells to heart
and wat do capillaries do? if blood cells are squeezing thorugh them then wats teh point of arteries & veins for transportation of blood. wats the difference?
me confused :o
btw wats GIT stand for
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GIT is just shorthand for gastrointestinal tract.
Capillaries facilitate gas exchange. So arteries carry the blood to the target tissue but the arteries are big. So one single artery would have the blood flowing through it quickly and there wouldn't be much opportunity for O2/CO2 exchange. The capillaries branch off and provide a huge surface area, which means that it's much easier/faster for products to be exchanged. Same way that surface area affects rates of reaction in chemistry.
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The blood doesn't transfer from the arteries to the tissues. It can't really get through them because the walls of the arteries are so thick. Instead, arteries transport blood to capillaries which then transfer the blood into tissues. You could think of arteries as the lead plumbing pipes underground which then lead to capillaries which are like sprinklers sprinkling water onto the lawn to provide it the nutrition it needs. Except in this case, it's more of a shower of fresh blood onto a lawn bed of human flesh.
...I swear I'm not crazy.
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haha ok. thanks guys for explaining.
more karma coming your way :)
GIT is just shorthand for gastrointestinal tract.
So it's also another word for the digestive system?
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haha ok. thanks guys for explaining.
more karma coming your way :)
GIT is just shorthand for gastrointestinal tract.
So it's also another word for the digestive system?
Yep, pretty much.
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Except in this case, it's more of a shower of fresh blood onto a lawn bed of human flesh.
...I swear I'm not crazy.
Just quoting this for posterity ;)