Biology hsc exam who ready!! (2 Viewers)

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Brontecat

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we sort've have the possibility that it'll be more abstract than usual too like the other exams

oh and with cmmunication what sort of things would we need to know for this dotpoint

"process information from secondary sources to outline the range of frequencies detected by humans as sound and compare this range with two other mammals, discussing possible reasons for the differences identified"

is it just to memorise the numbers?
 
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kevda1st

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ahhh thanks

another question!

Quarantine, main features and an example!
 

Xcelz

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well if swine flu came up, you would imagine that it would be in section 7 of the better health topic.

so you would want to talk about:
mentioning it as an infectious disease caused by pathogens.
the role of quarantine in preventing the spread of disease.
evaluating the effectivness of programs in preventing the spread.
possibly outline the strategies put in place if it became a pandemic, and future directions for management and control of these infectious diseases.

it will be hard for them to ask about it without mentioning any information for you to work with.
 

ekoolish

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what do we need to know about meiosis I'm confused !!!
Meiosis will be probably asked around Sutton and Boveri. And how boveri founded that the number of chromosomes is halved during meiosis and fertilization restores this full number of chromosomes.

Anyways, GL to everyone sitting the exam. :)
 

Xcelz

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well meiosis comes up in the chromosome area.


these are the dot points associated with meiosis i think.
  • sutton and boveri.
  • relationship between structure and behaviour of chromosomes during meiosis and the inheritance of genes.
  • the role of gamete formation and sexual reproduction in variability ofoffspring.
  • process information from secondary sources to demonstrates meiosis
sutton: observed meiosis in grasshopper testicles. he also put forward the chromosomal theory of inheritance as a result of this.

bullet point 2 : during division, chromosomes replicate. new chromosomes are attached by the centromere. in the 1st division the homologous chromosomes separate but double strands of the chromosomes are still joined. in the 2nd division the chromatids separate forming 4 gametes.

bullet point 3: talk about random segregation of the chromosomes, the crossing over of genetic material and random fertilisation. (the random fusing of gametes. sperm and ovum)
 
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simplyyme

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god im so screwed for bio :( i haven't had enough time to study it !!! can you help me with dot point

outline, using a simple model, the process by which DNA controls the production of polypeptides.

i know it has something to do with transcription, amino acids and translation, but it's more the process of understanding it that confuses the hell out of me
 

lilylullaby

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To: Kevda1st.

As Xcelz has mentioned, don't neglect to mention such things as for example; thermodetection at airports, where an increase in temperature suggests that the inflammatory response is in action, attempting to kill the pathogen. This would therefore suggest that the person may be ill and may need to be tested and quarantined. I hope this aids you.
 

lolrofllol

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god im so screwed for bio :( i haven't had enough time to study it !!! can you help me with dot point

outline, using a simple model, the process by which DNA controls the production of polypeptides.

i know it has something to do with transcription, amino acids and translation, but it's more the process of understanding it that confuses the hell out of me
making the model in class was meant to help you understand! After all, they may ask what the advantages of making a model were

anyway it goes like this

Transcription = mRNA copies gene for polypeptide template (uracil replaces thymine)
Translation = mRNA joins onto ribosome two codons (3 bases) at a time, tRNA with anticodon and amino acid join, peptide bond forms (from rRNA)

occurs until stop codon
 

simplyyme

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making the model in class was meant to help you understand! After all, they may ask what the advantages of making a model were

anyway it goes like this

Transcription = mRNA copies gene for polypeptide template (uracil replaces thymine)
Translation = mRNA joins onto ribosome two codons (3 bases) at a time, tRNA with anticodon and amino acid join, peptide bond forms (from rRNA)

occurs until stop codon

i don't think i was there for the model ... so probably why i have no idea lol
 

Xcelz

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Transcription is the process by which information ion the DNA is copied onto an RNA molecule. Translation is the process by which this information is used to make a new polypetide.
 

Xcelz

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i think by referring to the process through diagrams is what is meant by the model.

however here is a little more on the processes.

god im so screwed for bio :( i haven't had enough time to study it !!! can you help me with dot point

outline, using a simple model, the process by which DNA controls the production of polypeptides.

i know it has something to do with transcription, amino acids and translation, but it's more the process of understanding it that confuses the hell out of me
so dna holds information for creating proteins. (proteins are composed of polypetides.)

now there is 2 stages for production of polypetides. translation and transcription. i'll list a short and simple summary of what happens.

TRANSCRIPTION
  • DNA unwinds. so this ladder like double helix unzips.
  • The enzyme RNA polymerase catalyses the binding of RNA nucleotides to this unzipped strand. this becomes and mRNA strand.
  • this mRNA strand exits and enters the cytoplasm of the cell.
TRANSLATION
  • This mRNA strand binds to a ribosome.
  • tRNA brings an amino acid to the start codon on the mRNA.
  • The ribosome moves along the mRNA strand reading its bases.
  • this process continues til a stop codon on the mRNA is reached.
  • when this happens, the polypeptide chain is released into the cytoplasm.
 

theresekathryn

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god im so screwed for bio :( i haven't had enough time to study it !!! can you help me with dot point

outline, using a simple model, the process by which DNA controls the production of polypeptides.

i know it has something to do with transcription, amino acids and translation, but it's more the process of understanding it that confuses the hell out of me

1. DNA unwinds and unzips
2. Transcription - one side of the DNA is used as a base while free floating nucleotides align with their complematary bases, forming mRNA. At this point, U (uracil) replaces T (thymine)
3. mRNA leaves nucleus and enters cytoplasm, DNA rezips/rewinds
4. mRNA 'lies across' or attaches to ribosome
5. the ribosome holds 2 codons (1 codon = 3 bases) at a time.
Translation:
6. transfer RNA, or tRNA (which is 3 bases joined together with an amino acid on the end) bonds with the 'open' side of the mRNA
7. when there are 2 tRNAs side by side, a peptide bond forms between the amino acid, the ribosome moves down one codon, and the first tRNA leaves, leaving the amino acid attached
8. this process is repeated until a stop codon is reached
9. the chain of amino acids is called a polypeptide chain
10. the polypeptide undergoes further work (e.g. twisting into a particular shape, bonding with another polypeptide chain), and thus forms a protein
 

InterNut

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READY AS CAN BE


..to epically fail and fuck up my future.
/die hsc.
 
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