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homijoe

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o7nesss said:
does anyone do the genetics option???

i need helpp!!!

whats the difference between homologue, homeotic and hox genes???

gene Homologue's are sequences of dna that are found in many different species of organisms

Homeotic genes; are genes that control segmentation. That is they control the identity of each segement e.g whether a specific limb bud is destined to elongate & become an arm or a leg.

Hox gene: are genes which contol the morphogensis (organization of the body plan) of a developing embryo.
 

imqt

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if anyone here is doing the human story, which two evolutionary lines are you using and what evidence?
 
B

bekmay

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homijoe said:
Beadle and Tatum carried our research on the bread mould Neurosporo Crassa. They grew the mould on a minimal medium of sugar salts and the vitamin biotin. They reasoned that these substances were converted by the mould into amino acids and that enzymeswwere reresponsible for this. They subjected the mould to x-rays to cause mutations. They then tried to grow it on a minimal medium if it failed to grow they tried to grow it on a variety of media each containing a different amino acid. They found that the mutant strain had lost the ability to produce one amino acid this was because they lacked a particular enzyme. They then concluded that one gene codes for one enzyme and since enzymes are made of proteins it became know as the One gene-One protein hypothesis.

Distinguish between fungi and macro parasites. in terms of their distinguishable features and name 2 example of a disease caused by each type of pathogen
Fungi - eucaryotic cell with cell walls. Spreads via spores or rapid division, some infect the skin and the nails whereas others enter the host's body
examples are Tinea (athlete's foot) which is caused by fungus and Candidiasis (Thrush) which is caused by yeast.

A macroparasite is a multicellular organism. they are mostly arthropods or worms.
examples include house dust mite allergy and fascioliasis (sheep fluke disease).
 

imqt

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bekmay said:
Distinquish between the functions of B cells and T cells.

Both are lymphcytes and are interrelated working in conjuction with eachother in an immune response. T-cells are cell-mediated response to foreign atigens in the body. They are alerted directly by macrophages who display the fragments on their surface. T-Helper cells stimulates the differentiation of both T-cells and B-cells. T-cells differentiate in Helper T, Cytotoxic and Suppressor T cells. Helper T cells send a cytokine message to Plasma B cells. B Cells are antibody-mediated. Plasma B cell produced antibodies specific to the foreign antigen. Helper B cells are also produced and remain in the body for another invasion.

IDENTIFY THE CAUSE AND EFFECT RELATIONSHIP OF SMOKING AND LUNG CANCER
 

jozza80

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imqt said:
if anyone here is doing the human story, which two evolutionary lines are you using and what evidence?
Stupid bloody option in my opinion:

Do you mean the evolutionary tree?

Common Ancestor > A. ramidus > A. afarensis (P. robustus and P. boisei on seperate lines) > H. habilis > H. ergaster > H. Heidelbergensis > H. sapiens

I used evidence of cranial capacity (and muzzle angle/brain weight/body weight)..

Yet you could say many different lines because scientists interpret the fossil evidence in different ways. One thing however, most scientists agree on is that there have been four main evolutionary groups since our separation for the gorilla-chimpanzee stock. These are the australopithecines, habilines, erectines and humans; where the differences lie in how many species there are in each group and which particular species from each group is the ancestor of the next group!

Hence why I hate this stupid topic!!

If you wanna cross check notes and ideas (because such differences in opinions/texts) I'd be up for it..

Hope this helps?:cool:
 

Kujah

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imqt said:
if anyone here is doing the human story, which two evolutionary lines are you using and what evidence?
Or are you talking about the different evolutionary pathways proposed by scientists like Leakey or Johanson?
 

imqt

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jozza80 said:
Stupid bloody option in my opinion:

Do you mean the evolutionary tree?

Common Ancestor > A. ramidus > A. afarensis (P. robustus and P. boisei on seperate lines) > H. habilis > H. ergaster > H. Heidelbergensis > H. sapiens

I used evidence of cranial capacity (and muzzle angle/brain weight/body weight)..

Yet you could say many different lines because scientists interpret the fossil evidence in different ways. One thing however, most scientists agree on is that there have been four main evolutionary groups since our separation for the gorilla-chimpanzee stock. These are the australopithecines, habilines, erectines and humans; where the differences lie in how many species there are in each group and which particular species from each group is the ancestor of the next group!

Hence why I hate this stupid topic!!

If you wanna cross check notes and ideas (because such differences in opinions/texts) I'd be up for it..

Hope this helps?:cool:

HEY i hate this topic aswell! it really makes me hate studying bio. Its not only boring, but everything is so unclear, and its all about theories with no strong solid info.

um for my evolutionary theories that my teacher gave us
common ancestor ---> A afarensis (A africanus on a separate line)---> genus homo ---> young homo sapiens

common ancestor ---> A afarensis ---> A africanu ---> Genus Homo

does this seem right? i want to burn this topic so bad :angry:
btw thxs and yeh would love 2
 
Last edited:

imqt

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Kujah said:
Or are you talking about the different evolutionary pathways proposed by scientists like Leakey or Johanson?

im talking about this dot point

gather and process info. from seocndary sources to analyse and evaluate the evidence for two diff. models of human evolution
 

luucy

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Outline the current understanding of gene expression........this is so confusing! Its from the genetics topic
 

~Loz~

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Explain & describe the immune response in the human body in terms of:
-interaction between B & T lymphocytes
-the mechanisms tht allow interaction between b & T lyphocytes
-the range of T lymphocyte types & the difference in thier roles?
 

danz90

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imqt said:
IDENTIFY THE CAUSE AND EFFECT RELATIONSHIP OF SMOKING AND LUNG CANCER
Epidemiological studies have revealed that smokers have a 20-fold increase in the risk of developing lung cancer. A 2005 study in NSW by the Cancer Council showed that on average, ~27 females, and ~52 males, on average, per 1000 population develop lung cancer each year. Scientific analysis shows that many mutagenic and carcinogenic compounds are found in cigarette smoke, which can cause mutations in cells in lung tissue, thus causing lung cancer. Hence, smokers have a significantly (20-fold) higher risk of developing lung cancer, than non-smokers, on average.

Discuss the need for research to be continued for the production of artificial blood.
 

wazza.wins

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man, my bitch of a bio teacher left the entire class out to dry for the second half of this year. No pracs were done in class, it was up to ourselves to find the notes somewhere else. She just made us read the biotech booklets she copied and claimed as her own.
 
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imqt said:
IDENTIFY THE CAUSE AND EFFECT RELATIONSHIP OF SMOKING AND LUNG CANCER
It is difficult to say that something definitely causes a disease, even if it is common to all patients. Trends in lung cancer have been seen to reflect smoking habits, as a general decline in lung cancer and death in males has come at the same time as decreased smoking by men. Lung cancer has also been shown to rise 200% in women since the 70's, and it did not even exist before smoking started. Also over 40 chemicals from cigarette smoke have been proven to cause an increase in cancer in lab rats. Smoking and lung cancer have been linked many times in this way, but it is still difficult to get manufacturers to accept that smoking leads to lung cancer.

Microflora perform a number of roles on and in the body. Explain how microflora may become pathogens and cause a named disease.
 

luucy

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Discuss the need for research to be continued for the production of artificial blood.

- shortage of real blood
- real blood has to be cross matched which is a disadvantage in emergecy situations
- aftificial blood is free of infectious agents i.e HIV
- real blood only has a short shelf life 3-4 weeks
 

imqt

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danz90 said:
Epidemiological studies have revealed that smokers have a 20-fold increase in the risk of developing lung cancer. A 2005 study in NSW by the Cancer Council showed that on average, ~27 females, and ~52 males, on average, per 1000 population develop lung cancer each year. Scientific analysis shows that many mutagenic and carcinogenic compounds are found in cigarette smoke, which can cause mutations in cells in lung tissue, thus causing lung cancer. Hence, smokers have a significantly (20-fold) higher risk of developing lung cancer, than non-smokers, on average.

Discuss the need for research to be continued for the production of artificial blood.

Artificial blood and its importance is increasing today with an increasing shortage of donor blood. Using real blood is also very expensive as it needs to be cross matched, and be scanned of any infectious disease before it can be used. This is often costly in emergency situtations and does not meet the speedy requirements of surgery. Thus aritifical blood is needed. Currently there are perflurochemicals which are sterile, inert, stable, free of biological matter and carries 5 times more oxygen than normal blood. However it needed to be mixed with other chemicals. Dextrose solution containing glucose, water and salts is also used. However neither meets the maximum requirements of a proper alternative to real blood, and continue research is necessary

Outline Mendels experiments
 
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danz90 said:
Discuss the need for research to be continued for the production of artificial blood.
Donated blood is needed for patients with burns, anaemia, severe bleeding, low blood volume, etc. Artificial blood is a good substitute for this for a few reasons:
- the amount of blood needed by patients is far more than what is being donated.
- there is a slight risk of disease being transferred from biological blood. eg aids or hepatitus C .
- in emergencies it is useful to be able to give blood straight away, without knowing the blood type, something you can only do with artificial blood.
 

cutiepie123

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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
 

jozza80

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imqt said:
HEY i hate this topic aswell! it really makes me hate studying bio. Its not only boring, but everything is so unclear, and its all about theories with no strong solid info.

um for my evolutionary theories that my teacher gave us
common ancestor ---> A afarensis (A africanus on a separate line)---> genus homo ---> young homo sapiens

common ancestor ---> A afarensis ---> A africanu ---> Genus Homo

does this seem right? i want to burn this topic so bad :angry:
btw thxs and yeh would love 2
(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...
 

imqt

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aussiechick007 said:
It is difficult to say that something definitely causes a disease, even if it is common to all patients. Trends in lung cancer have been seen to reflect smoking habits, as a general decline in lung cancer and death in males has come at the same time as decreased smoking by men. Lung cancer has also been shown to rise 200% in women since the 70's, and it did not even exist before smoking started. Also over 40 chemicals from cigarette smoke have been proven to cause an increase in cancer in lab rats. Smoking and lung cancer have been linked many times in this way, but it is still difficult to get manufacturers to accept that smoking leads to lung cancer.

Microflora perform a number of roles on and in the body. Explain how microflora may become pathogens and cause a named disease.

Microflora is ususally harmless bacteria living in symbiotic relationship and is found in respiratory, reproductive areas etc It may become pathogens if wide spectrum antibiotics or harsh soaps are used and disrupt its population by killing the good bacteria. This enable pathogens to increase in numbers as they have more room to survive and are not met with the competiton of microflora. Candidiasis (Thrush) is an example. It is most common on the vagina, and can lead to rah, redness and other symptoms.
 

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