VCE Biology Question Thread

[katiesaliba]

Hmmm Dawn's (yes?) trolling I think.

You betcha.  :')

[cosine]

Hmmm Dawn's (yes?) trolling I think.

All complicated, in VCE Biology you'd get away with either one.


Actual reason is because of the order of things binding to the strand. A lot of TFs facilitate the binding of RNA pol to the DNA.

Yah just thought about it, if RNA polymerase supposedly unwinds the DNA, then obviously it attaches to the promoter region first xD

[vox nihili]

You betcha.  :')

Oh Dawn <3

Yah just thought about it, if RNA polymerase supposedly unwinds the DNA, then obviously it attaches to the promoter region first xD

It doesn't though.

[Sine]

Sorry I may have confused you with what I said. T helper cells ONLY bind with MHC II
- Cell mediated response
- APC engulfs pathogen and presents the antigen on it's MHC II
- Specific T helper cell binds to MHC II and is activated
- T helper cell activates cytotoxic T cell, the cells proliferate
- The specific cytotoxic T cell will now destroy any cell with foreign antigens on the MHC I

Humoral response
- APC engulfs pathogen and presents the antigen on it's MHC II
- Specific T helper cell binds to MHC II and is activated
- T helper cell activates B cell, which has bound with free antigens
- The B cell proliferates into plasma and memory cells
- Plasma cell produce antibodies against the specific antigen

So dug up this post, and from probably a couple of weeks ago which seems like the complexity VCAA would be going for. XD

Is their any double checking mechanism in cell-mediated immunity? like in humoral immunity where the B cell has to interact with the specific antigen first before being stimulated by the T-helper cell.

Also do we need to reference cytokines, such as interleukin-1 for the stimulation of the T-helper cell from the antigen presenting cell and T-helper cell producing interleukin-2 to stimulate B-cells and T-cytotoxic cells?

[Biology24123]

So dug up this post, and from probably a couple of weeks ago which seems like the complexity VCAA would be going for. XD

Is their any double checking mechanism in cell-mediated immunity? like in humoral immunity where the B cell has to interact with the specific antigen first before being stimulated by the T-helper cell.

Also do we need to reference cytokines, such as interleukin-1 for the stimulation of the T-helper cell from the antigen presenting cell and T-helper cell producing interleukin-2 to stimulate B-cells and T-cytotoxic cells?

Don't need to know the specific names of the cytokines, just know that they are signalling molecules. There probably is a double checking mechanism but you don't need to know it

[cosine]

So dug up this post, and from probably a couple of weeks ago which seems like the complexity VCAA would be going for. XD

Is their any double checking mechanism in cell-mediated immunity? like in humoral immunity where the B cell has to interact with the specific antigen first before being stimulated by the T-helper cell.

Also do we need to reference cytokines, such as interleukin-1 for the stimulation of the T-helper cell from the antigen presenting cell and T-helper cell producing interleukin-2 to stimulate B-cells and T-cytotoxic cells?

Nah, not really. The Helper T cell interacts with the MHC Class II markers of APCs and are activated. Once activated, they bind with complementary Cytotoxic T cells to also activate them and results in proliferation. The specific TCR's on Cytotoxic T cells recognise the specific antigen presented on virally infected cells, that actually present non-self antigens on their MHC I markers, or cancerous cells. Only B cells actually have to interact with the antigen first, in order to be activated. In fact, the antibodies on the B cell bind to the pathogen and actually engulf it, thus breaking it down and presenting the antigenic fragments on it's MHC II markers. This MHC II marker interacts with the Helper T cell to cause proliferation.

No, specific chemicals are not required, as I remember Mr. T-Rav saying a while back. Good to know, but not necessary. However, I think you may need to know that macrophages release interleukin in response to inflammation, to trigger the hypothalamus to increase core body temperature by vasoconstriction, thereby resulting in fever which may prevent or inhibit pathogenic activity.

[kimmytaaa]

Hi guys
For my last sac, I am required to do a media response on cloning a Neanderthal  child. We are allowed to bring in a sheet of A4 paper of notes in (one-sided). I have some information on the biological, technological and cultural evolution, the primates, hominid, the pros and cons of cloning. Is there anything specific that I am required to know for this sac.
Do I need to know about gene therapy and embryonic stem cells? 
Also, can someone also explain this question to me, i don't quite understand what its asking
The ability to clone a Neanderthal is an example of technological evolution requiring knowledge,skills and precision. Explain how biological and cultural development in humans have impacted upon our ability to be able to accomplish this specific technological advancement.

http://www.telegraph.co.uk/news/science/9814620/I-can-create-Neanderthal-baby-I-just-need-willing-woman.html
Thanks,
Have a nice day

[katiesaliba]

 
Also, can someone also explain this question to me, i don't quite understand what its asking
The ability to clone a Neanderthal is an example of technological evolution requiring knowledge,skills and precision. Explain how biological and cultural development in humans have impacted upon our ability to be able to accomplish this specific technological advancement.

http://www.telegraph.co.uk/news/science/9814620/I-can-create-Neanderthal-baby-I-just-need-willing-woman.html
Thanks,
Have a nice day

For this, talk about increasing brain size and its associated anatomical developments, as well as increased dexterity due to bipedalism, opposable thumbs, etc (biological developments). Eating red meat is a cultural development that facilitated the increase in brain size. You can also talk about the increased communication /expressiveness that came with brain development as this enabled the propagation of knowledge (cultural development).

Just some ides Best of luck!

[tashhhaaa]

is it worth learning details about the nervous system eg. CNS, PNS etc?

or is that too far off the study design?

[cosine]

is it worth learning details about the nervous system eg. CNS, PNS etc?

or is that too far off the study design?

Just know that:
CNS = Central Nervous System and is comprised of the brain and spinal cord, and the interneurones that interconnect sensory and motor neurones.
PNS = Peripheral Nervous System and is comprised of the sensory and motor neurones. Basically all the nervous mechanisms outside the brain and spinal cord. 

[cosine]

I thought endergonic reactions were actually reactions that anabolise reactants, and result in a net absorption of energy?

[cosine]

So even though these hormones initiate differing cellular responses, does this mean though that the receptors are still the same for the specific hormone, but the only difference in the hormone pathway is the signal transduction and hence the response?

In summary, is it true that hormones can act on target tissues/cells that possess the receptor complementary to the shape of the hormone? All this time I thought that hormones only acted on ONE target tissue, this incorrect?

[cosine]

I thought endergonic reactions were actually reactions that anabolise reactants, and result in a net absorption of energy?

Bump

[vox nihili]

I thought endergonic reactions were actually reactions that anabolise reactants, and result in a net absorption of energy?

That's an exergonic reaction, they've stuffed up.

Bump

Don't bump things you've only posted 9 minutes ago please.

is it worth learning details about the nervous system eg. CNS, PNS etc?

or is that too far off the study design?

Just know that:
CNS = Central Nervous System and is comprised of the brain and spinal cord, and the interneurones that interconnect sensory and motor neurones.
PNS = Peripheral Nervous System and is comprised of the sensory and motor neurones. Basically all the nervous mechanisms outside the brain and spinal cord. 

Agreed. The differences are covered in very little detail.

[mahler004]

So even though these hormones initiate differing cellular responses, does this mean though that the receptors are still the same for the specific hormone, but the only difference in the hormone pathway is the signal transduction and hence the response?

In summary, is it true that hormones can act on target tissues/cells that possess the receptor complementary to the shape of the hormone? All this time I thought that hormones only acted on ONE target tissue, this incorrect?

Epinephrine = adrenaline by the way, those funny Americans just spell it differently.

The answer is quite complicated. In this case, it's that the receptors (and the signal transduction pathways) are different. Both receptors are distinct, both bind adrenaline, and both activate different signal transaction pathways.

All this time I thought that hormones only acted on ONE target tissue, this incorrect?

This isn't true.