Biology Marathon 2006 (1 Viewer)

[simplistic]

[

Question: Compare the kidneys of fish and mammals

Question: Define the terms homeostasis and enantiostasis

Question: Contrast the theories of gradualism and punctuated equilibrium

Question: Explain how the environment affects the phenotype of an organism and give an example

whoever does all those first WINS![/quote]
in humans it functions as an osmoregulator as welll as part of the excreatory system to filter blood and remove waste and exess salt and water also plays a role in homeostasis
in the fish is acts as patr of the excreatory system however the gills are used to remove execss salt / water
homeostais is the process in which organisms maintian a relatively stable internal environment regardless of the external one
enaatiostasis is the process of maintaining metabolic and physilogical functions in response to variations in the external environment
gradual -->slows change which is constant in a million yrs the chnagw will be obivious evident thru transit fossils
puntuated--> short rapid burstd of chnage followed by a longer period or little to no chnage
depiste what the organims genotype is the environmet plays an important role in the phenotype.( affetcs a charectristics gene expression)eg hydrageas
in acidic soils flower color blueish were as in alkine soil flower color redish
the ph is altered due to the ions present within the soil such as aluminium

 

[simplistic]

dam lol

 

[Petinga]

Question from page before : selective breeding and hybridisation

Selective breeding is the careful selection and controlled mating of members of a species to produce offspring gradually with desired characteristics.
Hybridsisation involves producing offspring of two species of the same genus or two varieties of the same species.
Thus difference is that selective breeding requires same species but hybridisation is different varieties of the same species or same genus

 

[Petinga]

Simplistic, i believe one of your answers is incorrect. That is the one regarding the fish and mammals excretory system. The gills are used to remove nitrogenous wastes such as urea whilst excess salts/water removed in urine.

Question: Distinguish between:
- prions
-viruses
-protozoans
-macroparasites
-bacteris
-fungi

 

[Dr_Doom]

Prion - deformed protein found in brain and spinal chord which can cause other proteins to act like it. Contains no DNA (scrapie in sheep)

Virus - DNA covered by a protein coat, injects it's DNA into cells which replicate and invade host's nucleus. (influenze)

Protozoans - Eucaryotic organisms which are harmful to the body, trigger an immune response. Have a nucleus. (malaria)

Macroparasites - Can be seen with human eye, either internal or external. (tapeworm)

Bacteria - Prokaryotic organisms which are unicellular, can be harmful to the body and treated with antibiotics. (cholera)

Fungi - Eucaryotic organisms. They have spores which inject themselves into the host's tissue and live off the host. (ringworm)

Question: What are the methods used when mapping the human genome.

 

[Tim035]

tim i dont want to scare you lol but theire both in serach for the better health

Question: Describe inflammation response and phagocytosis

mast cells (infected cells) relesae chemicals such as histamine which initiate an immune response such as blood vessel dilation so taht more wbc can move into the area as well as keeping the pathogens in one spot( prevent thier spread)

phagocytosis is where nutrophile sand macrophages engulf and destroy antigens usuing lysososmes and digestive enzeymes
nutrophiles are shorter lasting and move in both blood and tissues were as macrphages (which are mature monocytes) are longer lasting and move thru the tissue part

K can you show me the SYLLABUS DOT POINT where it says discuss the work or something along the lines of that of those 2 scientists. I know the top of the syllabus page for the specific immune responce says something along the lines as "With Mcflarrenes discovery of the immune responce came a whole new understanding of how to cure and prevent disease" . And yes I've done a couple of multiple choice where its said: Which of the following scientists is responsible for our current understanding of the immune responce.
But no where is their a syllabus dot point, nor have I ever seen a question in part B on Burnett and never have I heard the name of that other scientist b4.

 

[berra]

K can you show me the SYLLABUS DOT POINT where it says discuss the work or something along the lines of that of those 2 scientists. I know the top of the syllabus page for the specific immune responce says something along the lines as "With Mcflarrenes discovery of the immune responce came a whole new understanding of how to cure and prevent disease" . And yes I've done a couple of multiple choice where its said: Which of the following scientists is responsible for our current understanding of the immune responce.
But no where is their a syllabus dot point, nor have I ever seen a question in part B on Burnett and never have I heard the name of that other scientist b4.

uhmm, not quite sure, but dnt think there actually is a syllabus dot point 4 that... not sure though...

i have a question:
describe the effect of one named genetic mutation on human health.

dus this include radiation????
and exactly were is it?
thnx heaps...

 

[nallask8r]

describe the effect of one named genetic mutation on human health

yeh think you can just crap on bout radition ie early 20th century x-ray noveltys and hiroshima, uv radiation and skin cancer. because all these alter the dna and polypeptide sequence, no?

but i would talk about beneficial mutations on human health - tolerance to high cholesterol levels in humans. Small village in Italy due to isolation, 40 villagers possess a mutation that alters a protein by one amino acid and makes it ten times more effective at mopping up excess cholesterol. (the villagers are descendants of one couple :s)

yeh i gotta pretty weird question... in past hsc papers it constantly has questions like this one
Justify ONE piece of information you would need in order to determine the
validity of the survey results. and State ONE other valid piece of information

Wat on earth is a piece of information? its so ambiguous

 

[Tim035]

Ummm I'm preety sure you'll find that question also had an extract involving an epidemiological study on smokers above it in which they concluded that smoking causes lung cancer. Without looking at the question I think the problem was they didn't have a control group of non smokers which they could compare the results to, the sample size was too small (only 100 ppl I think). And other variables such as location, exercise habits etc etc were not noted or controlled.

For the post a couple above, its not really a mutation but is sort of related. The fact that the incidence of people with sickle cell anemia in people who live in Malarial infested areas has greatly increased in recent times.
Also you can talk about the experiments done by Alexander Muller where he showed that as the dosage of x ray radiation exposed to Drosophilia was increased as did the number of phenotypic and teratogen mutations.
And of course theirs always the fact that Beadle and Tatum used X ray radiation to induce mutations in pink bread mould.

 

[simplistic]

K can you show me the SYLLABUS DOT POINT where it says discuss the work or something along the lines of that of those 2 scientists. I know the top of the syllabus page for the specific immune responce says something along the lines as "With Mcflarrenes discovery of the immune responce came a whole new understanding of how to cure and prevent disease" . And yes I've done a couple of multiple choice where its said: Which of the following scientists is responsible for our current understanding of the immune responce.
But no where is their a syllabus dot point, nor have I ever seen a question in part B on Burnett and never have I heard the name of that other scientist b4.

well both burnett and medawar won the nobel peace prize together about immunological tolerance cells. for the outcome H2 you can say that burntt stated the idea that if u place forgin tissue into an embryo at the right time it will not reject it later when exposed to it
it was medawar who tested this on mice
i dunno who the hell the other dude is but in wikipedia they said that he contributed somthing to health
vbmenu_register("postmenu_2628425", true);

petinga i was not sure of that part which is why i posted it to have people tell me if it was right that part is kind of hazy to me lol

 

[jesswatt]

Q: what is the host responce when infected with malaria

 

[Tim035]

Fair enough
I think trying to combine course outcomes with the other content to justify the need to know those 2 scientists would be preety cruel on behalf on the BOS. I think if they did ask a question they would need to give you some extract on the scientists & then they'd ask a question like "With your understanding of the immune responce, justify the importance of these 2 scientists work"
But really even thats like a 1/1000

 

[simplistic]

Q: what is the host responce when infected with malaria

the parasite plasmodium releasees chemicals which stimulate shivering sweating and fevers
the presence of the anitgen whill inittae an immune response resulting in the production of b and t cells
becaues the merozytes assexuall reporduse within red blodd cells and cauese them to burst .. the redusec number of RBC results int he patient being anemic and constantly tired

 

[nice]

okies my question;

1. explain how darwin/wallaces's theory of evolutiob by natural selection and isolation accounts for divergent evolution and convergent evolution?

2.describr the chemical nature of chrormosomes and genes

3.explain the relationship between the structure and behaviour of chromosomes during meiosis and the inhertiance og genes?---and do we need to learn this agrr

4. describe the contribution of pastur and koch to our understanding of infectious diseases


goodluck everyone!!!!!!!!!!!!!!!!!!!!!

 

[simplistic]

1. explain how darwin/wallaces's theory of evolutiob by natural selection and isolation accounts for divergent evolution and convergent evolution?

2.describr the chemical nature of chrormosomes and genes

3.explain the relationship between the structure and behaviour of chromosomes during meiosis and the inhertiance og genes?---and do we need to learn this agrr

4. describe the contribution of pastur and koch to our understanding of infectious diseases


1. has alredy been mentione dbefore
2.chromosomes consist of lenghts of dna wraped around protien ( histones0 6o % protien and 40 % dna
analogy : like beads on a string
the dna wraped around a histone is known as a nucleosome
gens are sections of dns which code for a charateristic and thus have the same compositions as chromosomes
3.well i just talk about meosis in depth concernrating on the chromosomes movemt them selves and the genes
and mention that crossong over and assortment occur and i got full marsk
4.http://arc.boardofstudies.nsw.edu.au/standards-packs/SP02_15030/
this was a good answer
basically stated that pasteur disproved spntaneous theory thru his classical experimrnt
he came up with pasturisation and vaccinations . he also stated the need of sterilisation to reduce spread of microbes
koch was responsible for deveoploing his postulates ( you can list them too )
he also studied antharax in sheep ( this led him to deveople his postulates)

sum up by saying : thru the contributions of both scientists todayd currnt understanding of the spread inf microbes and infections has increased .
it has led socieity to deveople preventtative measueres to reduce their incidence/ spread

 

[simplistic]

role of mhci and mhc ii

 

[Petinga]

I dnt believe it is neccessary to know mhc i and mch ii for the biology HSC course. Its beyond the scope of our course as it does not state it anywere in the syllabus. As well as that yuou do not need to know the host response of malaria it only asks the Histroical deveolpment of tratement and understanding of the cause of disease so jus need to knoq that Laveran discovered malaria is caused by plasmodium and other major discovereis that have increased our understanding.

So i will post a replacement question simplistic
Question:Idnetify one ectotherm and ectotherm and its response to variations in ambient temperatures of an environemtn

 

[simplistic]

identify data sources, gather, process and analyse information from secondary sources to describe one named infectious disease in terms of its:
o cause
o transmission
o host response
o major symptoms
o treatment
o prevention
o control
• To address this dot point, it is a good idea to select an infectious disease that interests you or that represents a significant problem in your community.
Use the list presented in the dot point to determine the type of information that you need to collect. Gather the information from a range of sources including digital technologies, locally available health brochures or phamphlets and the Internet. Process the accuracy of the information by looking for information that is consistently represented across a range of reputable publications. Analyse your information by developing accurate generalisations into short notes.
A good example of a named infectious disease is malaria. The following is a description of the disease.
Factors Description
Cause The parasitic protozoan, Plasmodium
Transmission Anopheles mosquito is the insect vector. Blood from a malaria victim contains Plasmodium sex cells. These form zygotes in cysts in the stomach wall of the mosquito and mature into sporozoites. When a cyst bursts, the sporozoites travel to the mosquito salivary glands, from where they are transferred to the victim of the mosquito bite. The sporozoites travel to the liver, multiply and then enter the red blood cells, where they also multiply. When the infected cells burst, they cause the malarial fever. Male and female gametes are produced from these sporozoites, which are then taken in the blood the next time a mosquito bites.
Host response When in the blood cells the host produces antibodies against Plasmodium
Major symptoms Chills, fever, sweating, delirium and headache
Treatment Anti-malarial drugs such as quinine and chloroquinine
Prevention Cover up after dark and use personal insecticide, mosquito nets
Control Draining swamps, spraying with insecticides.

 

[Dr_Doom]

You do if you're doing malaria for this point> I think most people are

* identify data sources, gather process and analyse information from secondary sources to describe one named infectious disease in terms of its:
o cause
o transmission
o host response
o major symptoms
o treatment
o prevention
o control

 

[simplistic]

Question:Idnetify one ectotherm and ectotherm and its response to variations in ambient temperatures of an environemtn

ectotherm :central netted dragon
an increase in ambient temp --> skin scale colur lightens to reflect solar heat ..
burrows underground lifts body over the ground to assist in heat loss thru converction currents lay in shade
decrease in temp--> sun bake coloue change to darker clours to absorb heat lie flat on ground to increase sa:v ration so that moew skin exposed to the sun
endotherm : red kangaroo
increase temp --> lick forearms decraes metabolims tail high sa:v ration thus heat lost panting and swaeting
decrease temp --> shiver sit in sun incrase metabolism