The Biological Question Thread

[sillysmile]

Hey there, I have created this question thread, because I am preparing my Unit 4 Biology notes, and intend to ask various questions in subsequent weeks. It's much simpler then multiple threads. If anybody else wishes to ask their own biology-related questions feel free to post them here. 

[sillysmile]

Okay, so I'm going to get right into it.
1. How can DNA be produced from messenger RNA, by using the enzyme reverse transcriptase?
2. What is the purpose and method of Genetic Transformation? Is it just another term for Recombinant DNA Technology?
thank you 

[Russ]

1. To make DNA you need a DNA polymerase. In our cells we only have DNA polymerase that works on DNA - we call it DNA dependent DNA polymerase. However, some organisms (viruses) have polymerases that are capable of making DNA from RNA. It doesn't necessarily have to be mRNA, but we call these enzymes "RNA dependent DNA polymerase".

So the name "reverse transcriptase" is a general term for those enzymes that allow us to go against Crick-Central dogma and produce DNA from RNA.

2. Genetic transformation is where DNA (usually fragments of DNA) is taken up by a cell and incorporated into the genome. It usually happens in bacterial cells, where they're capable of transporting environmental DNA across their cell wall and expressing it. It's not a synonym for recombinant DNA technology, which is where we combine two (or more) sequences of DNA, typically via restriction enzymes and plasmids.

[simpak]

COOL STORY ALERT: I got spammed by TSFX the other day being like DON'T WRITE OUT YOUR NOTES OR YOU WILL FAIL, BUY NOTES AND LECTURES FROM US.  Because I accidentally joined their mailing list for 2010 VCE (make it stop, they continuously send me crap).
And I was like 'lol, okay TSFX, because clearly that is the case'.
I spent like a month preparing my notes and no time involved with TSFX and I have clearly failed at life and am now living on the streets and stuff.

[sillysmile]

but they have a point there, you will fail year 12 if you don't use their notes. Nah jks, hahahaha!! that's hilarious...
seriously though, people are freaked out enough by the end-year exams as it is.

[happyhappyland]

COOL STORY ALERT: I got spammed by TSFX the other day being like DON'T WRITE OUT YOUR NOTES OR YOU WILL FAIL, BUY NOTES AND LECTURES FROM US.  Because I accidentally joined their mailing list for 2010 VCE (make it stop, they continuously send me crap).
And I was like 'lol, okay TSFX, because clearly that is the case'.
I spent like a month preparing my notes and no time involved with TSFX and I have clearly failed at life and am now living on the streets and stuff.

Its funny cos in unit 3 they sent me this list of questions for each subject and said "IF YOU DONT KNOW THESE QUESTIONS YOU NEED TO GO TO TSFX (something in that nature)." I read half the questions and most of them were irrelevant to the study design at all or were very obscure and unvcaa like..

[simpak]

TSFX is actually a joke imo (but no offence to people who go - it works for some people but lectures never usually work for me).
Therefore, it is easy to assume how much I enjoy learning in a University environment.

[Russ]

Therefore, it is easy to assume how much I enjoy learning in a University environment.

Oh you're just going to love next year if you transfer.

Anyway, I want more biology questions! I got all excited when I saw new posts in here

[lexitu]

Great! Love your exuberance

So here's a quick one to confirm for me: The non-coding strand (template strand) is complementary to the coding strand and also the mRNA molecule. The tRNA anti-codon is complementary to the DNA coding strand or is the equivalent of the DNA template strand in RNA language.

E.g. the DNA non-coding strand is TAA
the mRNA triplet is AUU
the tRNA triplet is UAA

Both Insight and Lisachem have stuffed this up in their exams and it really irked me. So I'm just making sure that my understanding is correcterino.

Cheers

[Russ]

Yeah.

That's probably the most confused part of genetics, because some resources use "template" to mean "coding"...

I just remember that coding = what we want = mRNA and then work the rest out from that. I don't think you'd really need to worry about the tRNA being complementary to the original DNA strand, just worry about how it relates to mRNA and the ribosome.

[lexitu]

Okay cheers for that

And LOL at my tRNA association - I was just being ultra descriptive for some reason. I'm not worrying about it

[TrueLight]

yep thats right... but i would use the word template and nontemplate strand... just makes it easier i guess

[simpak]

Therefore, it is easy to assume how much I enjoy learning in a University environment.

Oh you're just going to love next year if you transfer.

Anyway, I want more biology questions! I got all excited when I saw new posts in here

I know right, I sit in Psychology and that guy tries to explain QM things and I am like 'dude, I studied this for two years and I still have no idea what you are saying right now'.

Contribution: template and nontemplate ftw.

[sillysmile]

okay, what exactly is a barr body? and what is its purpose?
thank you

also, could somebody explain the blebs that are formed during apoptosis?
ty

[stonecold]

Great! Love your exuberance

So here's a quick one to confirm for me: The non-coding strand (template strand) is complementary to the coding strand and also the mRNA molecule. The tRNA anti-codon is complementary to the DNA coding strand or is the equivalent of the DNA template strand in RNA language.

E.g. the DNA non-coding strand is TAA
the mRNA triplet is AUU
the tRNA triplet is UAA

Both Insight and Lisachem have stuffed this up in their exams and it really irked me. So I'm just making sure that my understanding is correcterino.

Cheers

Just make sure you call the DNA a triplet, the mRNA a codon, and the tRNA an anticodon.