RECOMBINANT DNA TECHNOLOGY - AQA A LEVEL BIOLOGY + EXAM QUESTIONS RUN THROUGH
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- เผยแพร่เมื่อ 5 ก.ย. 2020
- In this video, I explain ALL of the content required for the "Recombinant DNA Technology" section for AQA A Level Biology. This includes: creating DNA fragment by reverse transcriptases, restriction endonucleases + the gene machine, amplifying DNA fragments by PCR + transformation using plasmids, marker genes and gene therapy. Time stamps are in the comments.
I also go through a few exam questions and explain their mark schemes.
The content in this video crosses over with other exam boards too.
Please leave a comment if you have any questions, I'll be more than happy to answer them!!! :)
00:28 = What is recombinant DNA technology?
01:16 = Producing DNA fragments: reverse transcriptase
04:19 = Producing DNA fragments: restriction endonucleases
07:05 = Producing DNA fragments: the gene machine
08:58 = Amplifying DNA fragments: PCR
11:48 = Transformation using plasmids
14:51 = Marker genes
17:28 = Gene therapy
19:45 = Exam questions and mark schemes
watching this 2 hours before my a level bio paper 2, thanks for your help.
Same omg and I hate this topic 😢
here too 💀
Loll same
Hi, do you need to know the advantages of PCR and the comparisons between Invitro an invivo, do you also need to know the advantages of isolating techniques like the use of reverse transcriptase? I have looked at the specification and it does not say specificly say you need to know the "advantages" or to compare them
Can you explain what you meant when you said oligonucleotides are "overlapping" DNA sections? Thank you
wow, thank you so much!
does a whole plasmid actual cross through the cell membrane (during transformation), is it not to big?
Yes! Heat shock causes the membrane to become more permeable, so the plasmid can pass through ☺️.
thanks for the video! just have a quick question - why won't the recombinant plasmids survive in agar plates? i thought they have antibiotic resistant genes? its shown in your slide at 17:22
Yes, but this is testing if the plasmids that have been taken up by bacteria are recombinant or not, not if the bacteria have taken up plasmids at all. A gene of interest is usually inserted into a marker gene (antibiotic resistance gene), disrupting the function of the antibiotic resistance gene, so if the plasmids are recombinant, the bacteria can't survive on the agar plate with antibiotic :)
@@AlevelBiologyHelp thank you so much, that makes sense! ☺️
Hi, I really love your videos and find them useful so I was wondering if you do any other subjects, especially aqa a level chemistry?
I don't at the minute, but I'm planning on making a Chemistry channel soon :)
If you’re looking for chemistry I’d recommend Allery Chemistry as they’re very specification specific and have separate videos on exam question practice too.
Get SNAPREVISE SERIOUSLY THEY BASICALLY TEACH YOU EVERYTHING AND PLUS YOU CAN ASK QUESTIONS AND YOU REVISION GUIDES LIKE FROM PMT
@@RAHMANISHMIL no
how does using the GFP help u identify the recombinant plasmid when the flouresene only happens once the gfp is made, so this would be the same as identifying the bacteria that have taken up recom plasmids?
@@AlevelBiologyHelp would this not mean that bacterial cells that have taken up recombinant plasmids will be identifiable by the fact that they do not glow as the DNA fragment has been inserted into the GFP gene, so recombinant plasmids will have a disrupted GFP gene so wont glow
@@bashredies8127 Yes, sorry for the mistake 😵💫
@@AlevelBiologyHelp bestie what does he mean im so lost lmao
How is it converted from cDNA to double stranded DNA when cDNA is double stranded already?
cDNA is originally only single-stranded since it's formed from RNA (which is single-stranded). The second stand is then formed by DNA polymerase. Hope this makes it more clear :)
@@AlevelBiologyHelp When you said reverse transcriptase can align the complementary DNA bases to mRNA bases, which DNA bases were you referring to?
Thank you!
@@chifumnanyauzoma-awunorthere are free floating nucleotides just existing in the cytoplasm. Those are the ones used for dna replication to create a new strand as well!
I feel good, I knew that I would, now
at 23:53 i dont understand the answer you put in how does promotor DNA mean the sheep isn't going to be killed?
Because the DNA is obtained from milk so the sheep doesn't need to be killed to get the DNA :)
How does a calcium ion solution increase membrane permeability?
Hi, as calcium ions are positively charged, they form an electrostatic bond with the phosphate groups of the phospholipid bilayer of the cell membrane, "neutralising" the charge. This means that the plasmid DNA is able to enter the cell (it wouldn't be able to do this without the calcium solution because DNA's negative charge would repel the charge on the phosphate groups). It's also a calcium chloride solution, may I add!! I hope this makes sense :)
8:45 whats ccna, did you mean cDNA or am i being dumb
Yes, cDNA :)
@@AlevelBiologyHelp my bad i should have realised 😅
222nd like :)