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nexttttt (3 Viewers)

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cutiepie123 said:
can some one tell me what the difference between a kidney in a marine and a fresh water is and why? i think im about to cry i feel i have forgotten EVERYTHING
marine fish:
- kidney contains few small glomeruli, due to the low filtration rate.
- small quantities of concentrated urine are produced.
- this is because the water concentration outside the body is lower than inside, so it is already losing water to the surroundings, so needs to conserve water in urine.

freshwater fish:
- kidney contains many large glomeruli, due to the high filtration rate.
- large amounts of very dilute urine are produced.
- this is because the water concentration is higher outside the body than inside it, so it is gaining too much water via passive transport, so must get rid of it in its urine.
 

danz90

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imqt said:
Outline Mendels experiments
For two years, Mendel bred pure-breeds of plants, for 7 different characteristics. lol from what i remember they were:
-tall and short
-round seed and wrinkled seed
-yellow pod and green pod
-terminal flowers and axillary flowers
lol cant remember the rest...

He then crossed pure breed (homozygous) plants to observe the characteristics in the offpsring, through a monohybrid cross. He did this by manually pollinating the stamens himself, and removed the filament/anther structure to prevent self-pollination. Mendel performed hundreds of crosses, determining the mendelian ratios. Hence, Mendel addressed both validity and reliability in his experiments, which led to the accuracy of his conclusions.

He came to conclusion that certain 'factors', whichw e now call genes, were dominant over other 'factors' etc etc.

How does reproductive technology, such as cloning, affect the genetic composition of a population?
 

imqt

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jozza80 said:
(good explanation in Spotlight text book...I think...)

I like the second one because it is supported by R. Leakey, the dude we need to know in that secondary sources dot point!

My advice would be to go to this link and have a look around: www.becominghuman.org

From what I remember it's pretty helpful..

What about the point: purpose of the Human Genome Project and briefly discuss its implications...
thanks!

well we got brief points on the Human Genome Project
What i know about it is that it is a international project that aims to map the genetic code of humans. It was started in 1990.

BENEFITS
- it gives the potential ability to cure genetic disease making it possible to look at a personas genetic code and decide their future. This could cause lifestyle changes to prevent the onset of disease. It could lead to the matching of tissues for organ donations and the production of medicines. It could also help find out more about human history

Implications
- insurance compnaies and employers may be able to access personal genetic records and make a decision based on a genetic disease which may develop. (for example, they will decide not to hire and train someone because they know they will get sick in 5 years time)
- its also very expensive and the rich can access such information



thats all i can think about?
 
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imqt said:
Outline Mendels experiments
Mended investigated 7 different characteristics in the garden pea plant. He first bred his experimental plants until pure to make sure there were no other factors present. He then cross bred alternate characteristics. eg. tall/short. All the first generation were observed to show the dominant characteristic in the pair, eg. in the example above, the first generation would be tall plants. He then self-pollinated the 2nd generation, and observed a 3:1 ratio of dominant to recessive traits. eg. 3 tall plants to 1 short plant.
Factors that contributed to his success include the fact that he first bred the plants until they were pure, used large numbers of plants, and hand pollinated the plants.

'All mutations are harmful'.
Discuss this statement.
 
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danz90 said:
How does reproductive technology, such as cloning, affect the genetic composition of a population?
Reproductive technologies such as cloning result in reduced genetic diversity in a population because the chosen individual is allowed to reproduce many times in a short period of time. In the process of cloning, cells from an organism are cultured to produce mature genetically identical organisms. This is useful for producing desirable characteristics quickly in species of crops, however as stated above, it does dramatically reduce the genetic diversity of a population.

Justify the use of vertebrate forelimbs as evidence to support the theory of evolution.
 

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aussiechick007 said:
'All mutations are harmful'.
Discuss this statement.
Mutations may be both beneficial and harmful. Some mutations of genes such as the tumor-supressor p-53 gene may cause uncontrolled cell growth leading to cancerous tumours that may be fatal. However, there are some chromosomal mutations that may create new alleles. These new alleles may bring about a new characteristic in gametes that may help a particular organism's offsprings survive or adapt better to the selective pressures in their environment. Hence, it is evident that not all mutations are harmful.

aussiechick007 said:
Justify the use of vertebrate forelimbs as evidence to support the theory of evolution.
Vertebrate forelimbs, such as the pentadactyl limb, provide evidence in supporting the evolutionary theory that certain vertebrates had originated from a common ancestor. Pentadactyl limbs feature a set of 5 phalanges,metacarpals, carpals etc. Vertebrates which have limbs with a similar structural base, can be said to have evolved from an ancestor which featured the pentadactyl limb, hence providing evidence for divergent evolution. For example, the presence of pentadactyl limbs in humans and some birds, may suggest that they once diverged from a common ancestor - the lobe-finned fish (lol as strange as it seems).

Question for people doing COMMUNICATION: Identify the areas of the cerebrum involved in the perception and interpretation of light and sound.

Question for the rest lol: Explain how public health programs, pesticides and genetic engineering strategies have controlled or prevent disease.
 
Last edited:

imqt

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danz90 said:
For two years, Mendel bred pure-breeds of plants, for 7 different characteristics. lol from what i remember they were:
-tall and short
-round seed and wrinkled seed
-yellow pod and green pod
-terminal flowers and axillary flowers
lol cant remember the rest...

He then crossed pure breed (homozygous) plants to observe the characteristics in the offpsring, through a monohybrid cross. He did this by manually pollinating the stamens himself, and removed the filament/anther structure to prevent self-pollination. Mendel performed hundreds of crosses, determining the mendelian ratios. Hence, Mendel addressed both validity and reliability in his experiments, which led to the accuracy of his conclusions.

He came to conclusion that certain 'factors', whichw e now call genes, were dominant over other 'factors' etc etc.

How does reproductive technology, such as cloning, affect the genetic composition of a population?
Cloning is producing identical copies of genetic material, leading to the exact same organism. This reduces genetic variations in a population as random segregation, random fertilisation and crossing over cannot occur as the organism is not produced naturally by meiosis. Other reproductive technologies include aritifical insemination which involves injecting male semen into female animals. This also limits genetic variation as all organisms inhibit the same alleles. This can prove disastrous for populations as a disease can kill them all since they all have the same genetic makeup, and there is no chance of developing resistance.
 

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btw DANZ90 hopefully i will see you at BPharmacy next year =)
 

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imqt said:
btw DANZ90 hopefully i will see you at BPharmacy next year =)
ooo awesome... hopefully will ;) :)
is it ur 1st pref? howd u go in stat?

did u go to the USyd open day this year and check out the pharmacy building nd labs?
 

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aussiechick007 said:
Reproductive technologies such as cloning result in reduced genetic diversity in a population because the chosen individual is allowed to reproduce many times in a short period of time. In the process of cloning, cells from an organism are cultured to produce mature genetically identical organisms. This is useful for producing desirable characteristics quickly in species of crops, however as stated above, it does dramatically reduce the genetic diversity of a population.

Justify the use of vertebrate forelimbs as evidence to support the theory of evolution.
forelimbs of several organisms share the same structure suggesting that they all share common ancestor. Pentadactyl limb found in reptiles, amphibians, mamales (human, whale) all consist of forearm bone, connected to a dual lower arm group, connected to wrist bones which connect to digits usually five in number......haha answer curtesy of Ahmad Shah Idil!!!!!
 

imqt

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aussiechick007 said:
Reproductive technologies such as cloning result in reduced genetic diversity in a population because the chosen individual is allowed to reproduce many times in a short period of time. In the process of cloning, cells from an organism are cultured to produce mature genetically identical organisms. This is useful for producing desirable characteristics quickly in species of crops, however as stated above, it does dramatically reduce the genetic diversity of a population.

Justify the use of vertebrate forelimbs as evidence to support the theory of evolution.

vertebrate forelimbs can provide insights into the evolution of organisms over time. For example all vertebrates have the pentadactyl limb. This suggests they evolved from a common ancestor. However, using only vertebrate forelimbs as evidence is not sufficient to make solid conclusions. Today, the use of bochemistry has proved to be very reliable and much more accurate than human observation as evolutionary relationships can be quantitatively analysed. EG Humans have a 97% protein precipition with Chimps. Therefore, using biochemistry and making use of our increasing knowledge of genes and chromosomes more accurate conclusions can be made to support the theory of evolution
 

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aussiechick007 said:
Reproductive technologies such as cloning result in reduced genetic diversity in a population because the chosen individual is allowed to reproduce many times in a short period of time. In the process of cloning, cells from an organism are cultured to produce mature genetically identical organisms. This is useful for producing desirable characteristics quickly in species of crops, however as stated above, it does dramatically reduce the genetic diversity of a population.

Justify the use of vertebrate forelimbs as evidence to support the theory of evolution.
The pentadactyl limbs of tetrapod vertabrates are homologous structures (have the same genetic basis despite having different appearances and sometimes different functions). The also originate from the same location on the embreyo, suggesting that they originated from a forelimb on a shared ancestor. This is evidence for the theory of evolution as it suggests that these organisms diverged from a common ancestor.

EDIT: you did it again :p
 

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danz90 said:
ooo awesome... hopefully will ;)
is it ur 1st pref? howd u go in stat?

did u go to the USyd open day this year and check out the pharmacy building nd labs?

na i couldnt make it to USyd open day but my friends went and told me its great

um yeh passed STAT test, such a relief because didnt think i could make it. How about you? and yes its my first preference :) ...its obviously yours ?
 

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imqt said:
na i couldnt make it to USyd open day but my friends went and told me its great

um yeh passed STAT test, such a relief because didnt think i could make it. How about you? and yes its my first preference :) ...its obviously yours ?
yeahh the pharm building looks like a little cottage from the outside lol.. but its pretty cool inside (still got that antique feel tho). the labs are niceee i like them, but they are also old school.

if u got 150+ in STAT, which you obviously have... then you're half way there. :) i ended up getting 162. I got confirmation from Faculty of Pharmacy that STAT cut-off for 2009 is 150/200. wooot.

yehhh definitely 1st preference.
 

midifile

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Discuss the difficulties in defining the terms health and disease
 

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aussiechick007 said:
anyone want to post more questions ? or will we just answer them ? :p :)
yeah i posted one a bit further up.

Question for the rest lol: Explain how public health programs, pesticides and genetic engineering strategies have controlled or prevent disease.
 

imqt

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danz90 said:
yeahh the pharm building looks like a little cottage from the outside lol.. but its pretty cool inside (still got that antique feel tho). the labs are niceee i like them, but they are also old school.

if u got 150+ in STAT, which you obviously have... then you're half way there. :) i ended up getting 162. I got confirmation from Faculty of Pharmacy that STAT cut-off for 2009 is 150/200. wooot.

yehhh definitely 1st preference.

haha i got 160/200

im just glad i got over 150, i was jumping up and down is excitement
a little cottage?:confused: thats sounds eww... i want some advance, modern high tech building :bomb:
 

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midifile said:
Discuss the difficulties in defining the terms health and disease
Health is not merely the absence of disease; it incorporates social, psychological and physiological wellbeing. It is very difficult to determine at any one time whether an individual is 'healthy'.. since we are all affected by various factors in social, psychological and physiological wellbeing at any one time.

Disease refers to an impairment of the structure and functioning of the human body. In this way, it is difficult to categorise certain injuries or conditions as diseases. For example, if someone 'winded' you in a footy match, then is that really a disease? by definition it is, since the structure and function of the diaphragm is affected.

I don't think this is right btw, I studied this quite a while ago and isn't that clear in my head.
 

imqt

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midifile said:
Discuss the difficulties in defining the terms health and disease


they are both very subjective and have many components. It really depends on what the person themselves effects their health to be. For example a 50 year old, has very different exoectations to a 5 year old interms of their health. In general terms health is the state of complete mental, social and physcial wellbeing. Health is not necessarily the absence of disease. Disease is the state of impaired functioning of these components.
 

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