mitochondria
*Rawr*!
Umm... sorry about the missing tips, I just finished that night and never came back again 
Anyways, thinking that I should make an edition to the dodgy tip I had here before.. Hopefully the following information are still accurate
1. The concept of genes can be confusing for some people. Just remember that as a unit of heredity composed of DNA and link this to mitosis when you are asked about mitosis. Together they ensure cells are reprocuded (asexually) in the body accurately. Also, don't mix up cell differentiation and specialisation. They sound like they same thing and yet differentiation has to occur first to allow the specialisation of cells. Differentiation cause a primitive cell to form into certain irreversible structure which will perform a certain task after specialisation. Think about how the system always tries to keep cells duplicated correctly when you are answering questions about maintainance and repair.
2. Know that infectious diseases are caused by pathogens and non-infectious diseases are not. Very often there is a confusion about infectious caused by non-organic chemicals but that is actually under the environmental category under non-infectious disease, be aware of that. You are also required to know that there are different types of pathogens, some common mistakes made in infectious disease-pathogen related concepts are: (i) all pathogens are made cells of or are cells; (ii) macro-organisms such as tapworm, ticks... etc. are not pathogens; (iii) pathogen and antigen are interchangable terms.
3. It is sometimes hard to define pathogen because it consists of a range of disease causing agents. It is, however, not right to define pathogen merely as a disease causing agent because non-organic chemicals can also cause disease. Also, it is not possible to define pathogens as any organisms that causes diseases due to the nature of virus and prions. This definition I use maybe inaccurate, but it describes the feature of all kinds of pathogen accurately: an organic body or matter which has the ability to reproduce either sexually or asexually and causes disease in living organisms.
4. Know what a Petri dish is and the procedures needed to produce a culture of microbes. Utilise this information when you are answering a question which requires you do so.
5. Know what Pasteur and Koch did. Don't just remember them, because that won't help if you tend to forget things in exams (also, if you only remember things you are less flexible even if you remember everything). For Pasteur, make sure you study the followings:
- The Swan-neck flask experiment (proved his theory that contamination in food can be caused by microbes in the air)
- Pasteurisation
- Showed that air-borne microbes were the cause of diseases
- Developed vaccination for cholera, anthrax and rabies
- Sheep experiment
Koch:
- Koch's postulate
- Successfully isolated the bacterium that caused anthrax (did the same with TB) and developed techniques for other scientists to use
- Has shown that a microbe is directly related to a disease which Pasteur had not done so
If you the question also requires you to address the significance/contribution of theie work, you could talk about the fact that both of their work has helped to develop the relationship of diseases and microbes and have also disproved the theory of spontaneous generation.
6. Know the pathogens specified in the syllabus in terms of their structures, chemical compositions.. etc. and of course be able to name at least one disease caused by each type of pathogen as required.
7. Know your malaria (caused by the Plasmodia protozoans) And again, if you can find a picture, study from it instead of remembering a written account of malaria with all those sporozoites and mesozoites which drive you crazy. Also know that the female anopheles is the *vector* of the disease.
8. Know one infectious disease throughoutly. There's nothing preventing you from using malaria if you encounter this question. If you have more *disk space* I would suggest you to study other common infectious diseases such as influenza and thrush are quite common. If you forget about what you have study or that you haven't studied (I hope you did study though), make things about a disease you know about isn't quite difficult. If wrose comes to wrost, go macro! Use parasites! They are still pathogens which cause infectious diseases.
9. Know how antibiotics work and remember that they will eventually "not-work". You can also relate this to evolution (a population which have resistance to the antibiotics survives.. the reproduce and so on..) to explain this phenomonenon
10. Know the mechanisms contained in the first, second and final level of the body's defence against pathogens/possible pathogens. Basically you don't have to know about the first and second line of defence in-depthlyp), just remember their names and you can pretty much figure out what they do. Learn the third line of defence throughoutly!
11. Understand what antigens are and its relation with pathogens. By understanding what antigens are you will also have to be able to identify that it triggers the immune systems and that our body can identify self and non-self proteins. Use this information to explain the problems encountered with organ transplants.
12. Recognised the basic difference between T-cells and B-cells: T-cells are respobsible for cell-mediated reponse and B-cells are respobsible for antigen-mediated response (also known as humoural response). After that, study the relationships of these cells and white blood cells and how they all work together by using a diagram. Many terms under this particular topic seems to be interchangable but they are actully different things: for leucocytes are not the same as lymphocytes (since lymphocytes is a subdivision of leucocytes, i.e. lymphocytes are leucocytes but leucocytes do not necessarily have to be lymphocytes); interleukins, interferons and cytokines are also not interchangable (again, interleukins and interferons are cytokines but not the other way around). Some textbooks tells you that ony B-cells secret antibodies - and that is not true. However, if you are doing internal exams and you can't be bothered arguring with your bio teacher or you bio teacher refuse to accept this fact then you'll be better off saying that B-cells are the only cells which will produce antigens. *Continued* ...
13. ... *From 12* Identify the type of T-cells and B-cells there are. For T-cells, the main types are Cytotoxic, Surpressor, Helper and Memory; for B-cells, the main types are Plasma and Memory (there are lots in the Heinemann textbook I think.. but I don't have it with me so I can't check.. If you want more information, find that book or post a message if you can't find it. And about other types of T-cells and B-cells which you could mention, you will have to decide whether those are out of the scope of your study (i.e. the HSC Biology course).) Something to make sure you don't get confused is this: T-cells are derived [through differentiation] in the bone marrow and migrate to the thymus gland to mature [specialisation]; on the other hand B-cells are derived and is NOT matured in the thymus gland but mostly in the bone marrow.
14. You pretty much have to do the same thing for non-infectious disease as well as those mentioned above. You have to know how many types of non-infectious disease there are: environmental, inherited and nutritional and identify at least one disease caused by each of these factors. Then you will have to do another throughout study on an non-infectious like the one you did in the infectious one. Non-infectious diseases are actually easier than infectious consider there are less complex biological concepts in this area (in the syllabus). Common disease you can use are anorexia nervosa (this one is trick in terms of defining what type it is, but it is quite fun), Minamata disease (mercury poisoning, you can google a loooooooooot of informationf on this), haemophilia... etc.
15. Hint: Epidemiological study is easy as long as you can think clearly and structurally. You have to be able to analyse different aspect of a given situation. That question in the 2003 biology paper was quite unexpected consider that it was only a tiny bit in the syllabus and that was 8 mark (or could have been 7.. I think it was 8 though). As long as you can think straight and organise your points, you will have no problems with epidemiological study questions whether they are case studies or investigation plan like the one in last year's HSC.
16. The quarantine bit is probably the easiest and yet most boring part of the biology syllabus - all you have to do is to remember things (they are common sense anyway). All you need is a good memory for this part of the syllabus and study some cases. Then you are fit to go into exams
Okay.. finally.. please make me to correct this if there are any mistakes Have fun studying and good luck with the HSC!
Anyways, thinking that I should make an edition to the dodgy tip I had here before.. Hopefully the following information are still accurate 1. The concept of genes can be confusing for some people. Just remember that as a unit of heredity composed of DNA and link this to mitosis when you are asked about mitosis. Together they ensure cells are reprocuded (asexually) in the body accurately. Also, don't mix up cell differentiation and specialisation. They sound like they same thing and yet differentiation has to occur first to allow the specialisation of cells. Differentiation cause a primitive cell to form into certain irreversible structure which will perform a certain task after specialisation. Think about how the system always tries to keep cells duplicated correctly when you are answering questions about maintainance and repair.
2. Know that infectious diseases are caused by pathogens and non-infectious diseases are not. Very often there is a confusion about infectious caused by non-organic chemicals but that is actually under the environmental category under non-infectious disease, be aware of that. You are also required to know that there are different types of pathogens, some common mistakes made in infectious disease-pathogen related concepts are: (i) all pathogens are made cells of or are cells; (ii) macro-organisms such as tapworm, ticks... etc. are not pathogens; (iii) pathogen and antigen are interchangable terms.
3. It is sometimes hard to define pathogen because it consists of a range of disease causing agents. It is, however, not right to define pathogen merely as a disease causing agent because non-organic chemicals can also cause disease. Also, it is not possible to define pathogens as any organisms that causes diseases due to the nature of virus and prions. This definition I use maybe inaccurate, but it describes the feature of all kinds of pathogen accurately: an organic body or matter which has the ability to reproduce either sexually or asexually and causes disease in living organisms.
4. Know what a Petri dish is and the procedures needed to produce a culture of microbes. Utilise this information when you are answering a question which requires you do so.
5. Know what Pasteur and Koch did. Don't just remember them, because that won't help if you tend to forget things in exams (also, if you only remember things you are less flexible even if you remember everything). For Pasteur, make sure you study the followings:
- The Swan-neck flask experiment (proved his theory that contamination in food can be caused by microbes in the air)
- Pasteurisation
- Showed that air-borne microbes were the cause of diseases
- Developed vaccination for cholera, anthrax and rabies
- Sheep experiment
Koch:
- Koch's postulate
- Successfully isolated the bacterium that caused anthrax (did the same with TB) and developed techniques for other scientists to use
- Has shown that a microbe is directly related to a disease which Pasteur had not done so
If you the question also requires you to address the significance/contribution of theie work, you could talk about the fact that both of their work has helped to develop the relationship of diseases and microbes and have also disproved the theory of spontaneous generation.
6. Know the pathogens specified in the syllabus in terms of their structures, chemical compositions.. etc. and of course be able to name at least one disease caused by each type of pathogen as required.
7. Know your malaria (caused by the Plasmodia protozoans)
And again, if you can find a picture, study from it instead of remembering a written account of malaria with all those sporozoites and mesozoites which drive you crazy. Also know that the female anopheles is the *vector* of the disease.8. Know one infectious disease throughoutly. There's nothing preventing you from using malaria if you encounter this question. If you have more *disk space* I would suggest you to study other common infectious diseases such as influenza and thrush are quite common. If you forget about what you have study or that you haven't studied (I hope you did study though), make things about a disease you know about isn't quite difficult. If wrose comes to wrost, go macro! Use parasites! They are still pathogens which cause infectious diseases.
9. Know how antibiotics work and remember that they will eventually "not-work". You can also relate this to evolution (a population which have resistance to the antibiotics survives.. the reproduce and so on..) to explain this phenomonenon
10. Know the mechanisms contained in the first, second and final level of the body's defence against pathogens/possible pathogens. Basically you don't have to know about the first and second line of defence in-depthly
p), just remember their names and you can pretty much figure out what they do. Learn the third line of defence throughoutly!11. Understand what antigens are and its relation with pathogens. By understanding what antigens are you will also have to be able to identify that it triggers the immune systems and that our body can identify self and non-self proteins. Use this information to explain the problems encountered with organ transplants.
12. Recognised the basic difference between T-cells and B-cells: T-cells are respobsible for cell-mediated reponse and B-cells are respobsible for antigen-mediated response (also known as humoural response). After that, study the relationships of these cells and white blood cells and how they all work together by using a diagram. Many terms under this particular topic seems to be interchangable but they are actully different things: for leucocytes are not the same as lymphocytes (since lymphocytes is a subdivision of leucocytes, i.e. lymphocytes are leucocytes but leucocytes do not necessarily have to be lymphocytes); interleukins, interferons and cytokines are also not interchangable (again, interleukins and interferons are cytokines but not the other way around). Some textbooks tells you that ony B-cells secret antibodies - and that is not true. However, if you are doing internal exams and you can't be bothered arguring with your bio teacher or you bio teacher refuse to accept this fact then you'll be better off saying that B-cells are the only cells which will produce antigens. *Continued* ...
13. ... *From 12* Identify the type of T-cells and B-cells there are. For T-cells, the main types are Cytotoxic, Surpressor, Helper and Memory; for B-cells, the main types are Plasma and Memory (there are lots in the Heinemann textbook I think.. but I don't have it with me so I can't check.. If you want more information, find that book
or post a message if you can't find it. And about other types of T-cells and B-cells which you could mention, you will have to decide whether those are out of the scope of your study (i.e. the HSC Biology course).) Something to make sure you don't get confused is this: T-cells are derived [through differentiation] in the bone marrow and migrate to the thymus gland to mature [specialisation]; on the other hand B-cells are derived and is NOT matured in the thymus gland but mostly in the bone marrow.14. You pretty much have to do the same thing for non-infectious disease as well as those mentioned above. You have to know how many types of non-infectious disease there are: environmental, inherited and nutritional and identify at least one disease caused by each of these factors. Then you will have to do another throughout study on an non-infectious like the one you did in the infectious one. Non-infectious diseases are actually easier than infectious consider there are less complex biological concepts in this area (in the syllabus). Common disease you can use are anorexia nervosa (this one is trick in terms of defining what type it is, but it is quite fun), Minamata disease (mercury poisoning, you can google a loooooooooot of informationf on this), haemophilia... etc.
15. Hint: Epidemiological study is easy as long as you can think clearly and structurally. You have to be able to analyse different aspect of a given situation. That question in the 2003 biology paper was quite unexpected consider that it was only a tiny bit in the syllabus and that was 8 mark (or could have been 7.. I think it was 8 though). As long as you can think straight and organise your points, you will have no problems with epidemiological study questions whether they are case studies or investigation plan like the one in last year's HSC.
16. The quarantine bit is probably the easiest and yet most boring part of the biology syllabus - all you have to do is to remember things (they are common sense anyway). All you need is a good memory for this part of the syllabus and study some cases. Then you are fit to go into exams
Okay.. finally.. please make me to correct this if there are any mistakes
Have fun studying and good luck with the HSC!