VCE Biology Question Thread

[Sine]

Yo can someone answer this doubt?:
if PCR amplifies a DNA sample, why would gel electrophoresis normally used after PCR? PCR would produce the same size fragments at each cycle no?
thnx

PCR would be used to amplify a DNA sample as you say. For example from a crime scene where there is only a very small sample of undamaged DNA. PCR does produce the same "size" of fragments but you need to amplify initial DNA so that you can properly observe using gel electrophoresis.

[kjistsehrtot]

I don't know if this will help, but the particles want to move so they are spread out, just like people on a train. If there is half the carriage empty, people will spread out roughly evenly throughout. The will not stay cramped together in one half of the carriage if there is a lot of empty space on the other side because people don't like being squished close together if it's not necessary to be --> just like the particles, therefore they will diffuse evenly around the train.
So that means they will move along the concentration gradient towards the empty space and away from the cramped area.

thank you so much this makes a lot of sense!! <3

[YussifK]

Would anyone please help me make my scientific poster(year 10) I want some feedback and  improvements.. to score high please guys please guys... if your interested in helping me feel free to to reply back....

Thank you (( this is so important I really want to prove to my dad I’m Not DUMB

[ssillyssnakes]

Would anyone please help me make my scientific poster(year 10) I want some feedback and  improvements.. to score high please guys please guys... if your interested in helping me feel free to to reply back....

Thank you (( this is so important I really want to prove to my dad I’m Not DUMB

What kind of help are you looking for? If you have questions, I, and I'm sure anyone else in this forum, will be happy to help! As long as it isn't just doing the work for you

[YussifK]

What kind of help are you looking for? If you have questions, I, and I'm sure anyone else in this forum, will be happy to help! As long as it isn't just doing the work for you

Na man I ain’t lazy I don’t wanna anyone’ to do my work... I was just saying if someone can’t help me make my scientific poster better basically I want important key feedback that would help

[ssillyssnakes]

Well I'm open to helping!

[YussifK]

Well I'm open to helping!

Omg u serious

[Poet]

Omg u serious

AN is here for the sole purpose of helping students. Of course we're here to help you!

The thing is, as snakes said, you need to take initiative. We can't help you through the entire process - it has to be your own.
Why not work on the poster and get back to us when you think you've fulfilled the criterion? We can definitely give you more specific feedback and tips once we have a better foundation.

Please remember to keep the chatter to a minimum. This is a question thread, not a general discussion.

[YussifK]

AN is here for the sole purpose of helping students. Of course we're here to help you!

The thing is, as snakes said, you need to take initiative. We can't help you through the entire process - it has to be your own.
Why not work on the poster and get back to us when you think you've fulfilled the criterion? We can definitely give you more specific feedback and tips once we have a better foundation.

Please remember to keep the chatter to a minimum. This is a question thread, not a general discussion.

I’m finished but I don’t wanna hand it in... I want smart feedback and improvements... please

[Poet]

I’m finished but I don’t wanna hand it in... I want smart feedback and improvements... please

would you be able to link it for us? You can post it in a reply to this thread by clicking the "attachments and other options" button just below the text box and choosing the file you'd like us to review. If the file is too big, you can make a Dropbox link. It would be great to also give us a criteria sheet/instructions/marking rubric if your teacher gave you one to look at.

[YussifK]

would you be able to link it for us? You can post it in a reply to this thread by clicking the "attachments and other options" button just below the text box and choosing the file you'd like us to review. If the file is too big, you can make a Dropbox link. It would be great to also give us a criteria sheet/instructions/marking rubric if your teacher gave you one to look at.

I have the rubric sheet.. but I don’t understand it fully the language is to complex... I’ll send it tomorrow I need to go to my brothers funeral 😭

Thank you

[caqiu]

just a quick question
this is my definition for the founder effect - the founders effect occurs when a small, non-representative group of individuals from a larger population moves to new location and establish a new population.
and then I have a little description about it -  the smaller gene pool is unlikely to reflect the allele frequency of the original population. There is an increase of inbreeding in the 'founder population' and reduced genetic variation. In the new environment, the environmental pressures on the founder population are likely to be different fro those experience by the original population. These differences in environmental pressures drive further changes in the allele frequencies and ultimately evolution.

However I read somewhere, that I shouldn't include anything about selection pressures (e.g. the part about environmental change) as that is a part of natural selection, is this correct? If I remove the last part, is there anything I need to add e.g. more subjected to genetic drift

Thank you in advance!

[Erutepa]

just a quick question
this is my definition for the founder effect - the founders effect occurs when a small, non-representative group of individuals from a larger population moves to new location and establish a new population.
and then I have a little description about it -  the smaller gene pool is unlikely to reflect the allele frequency of the original population. There is an increase of inbreeding in the 'founder population' and reduced genetic variation. In the new environment, the environmental pressures on the founder population are likely to be different fro those experience by the original population. These differences in environmental pressures drive further changes in the allele frequencies and ultimately evolution.

However I read somewhere, that I shouldn't include anything about selection pressures (e.g. the part about environmental change) as that is a part of natural selection, is this correct? If I remove the last part, is there anything I need to add e.g. more subjected to genetic drift

Thank you in advance!

While the divergent evolution of the founder population due to a different environment may indeed occur, it is not a part of the founder effect as such since the founder effect is a chance event, and natural selection isn't a chance event.
Your definition aside from that is pretty good, you may however want to include that thr founders effect is a chance event, or that the founding population is no representative by chance.
Hope this helps!

[coldairballoon]

How much should we actually know about action potentials? My teacher seems deadset on making us learn absolutely everything, from thresholds to the polarisation and all the other stuff, but from what other people tell me I should really only need to know about neurotransmitter diffusion (ca2+ ions entering terminal, exocytosis, diffusion, reception, etc.). Anyone know?

[Erutepa]

How much should we actually know about action potentials? My teacher seems deadset on making us learn absolutely everything, from thresholds to the polarisation and all the other stuff, but from what other people tell me I should really only need to know about neurotransmitter diffusion (ca2+ ions entering terminal, exocytosis, diffusion, reception, etc.). Anyone know?

Action potentials have been completely removed from the study design. All you need to know is that neurotransmitters are a signalling molecule that communicates messages between neurons.