Last minute clarifications needed :( (1 Viewer)

[planino]

a. With whole organism cloning, is the surrogate mother the same species as the organism that is being cloned?
b. My Bt cotton production method is really sketchy:
1.Cotton seedlings are cut, placed onto a growth medium, and grown into callus cells (aggregate of undifferentiated cells). After a few weeks, they’re transferred to a liquid medium where hormones are added to induce them to grow into cotton plant embryos
2.Restriction enzymes used to remove the Bt gene from Bacillus thuringiensis bacteria and added to a carrier bacterium that is able to insert genes into other cells.
3.The cotton plant embryos are dipped into a solution containing a mixture of a vector (bacteria that can inject genes into organisms)) and the extracted Bt genes, and the vectors inject the Bt genes into the cotton cells
4.The Bt gene-containing embryos are grown in tissue culture, transferred to another growth medium. Eventually these germinate into small Bt cotton plants.

Please help me fix it, and correct any mistakes

c. Also, I'm a little unsure about my tissue culture/plant cloning method:
1. Tissue sample is cut from a superior plant and is placed in nutrient culture
2. The tissue sample of the plant grows within the nutrient culture into calluses – aggregate of undifferentiated cells
3. The undifferentiated cells can then thrive within the tissue culture and form specialised parts like leaves, stems etc.
4. Eventually, a small plant/s is formed – clone of the original plant. This plant can then be transplanted into a pot and nurtured in a greenhouse

d. [Genetics: Code Broken?] Would it be safe to assume that the gene cloning/producing recombinant DNA methods are basically identical?

e. [Genetics: Code Broken?] With gene cloning, are MULTIPLE genes from the organism taken out by restriction enzymes and placed into MULTIPLE plasmids, or is only one gene taken out with a restriction enzyme and spliced into one plasmid?


f. [Genetics: Code Broken?] Gene expression. Help.


Thank you in advance, and I'll be back with more last minute questions

 

[superSAIyan2]

a) Yes. for example in cloning Dolly the sheep, the surrogate is also a sheep. It does not have to be the same type of sheep though.
b) It seems too long. You can say the seedlings are grown in the hormone rich medium from the beginning as this stimulates root/shoot development. Also i thought that a viral vector is used. Dont think this will matter much.
c)Seems fine

d)Yes, both are basically locating and extracting a gene from a chromosome and inserting it into a plasmid. However, in gene cloning the gene is often extracted for commercial use, but not always when producing recombinant DNA.

e) You are only cloning ONE gene of interest, so i'd say the latter

f) The basics : Gene expression regulates when and where polypeptides can be synthesised, which determines protein synthesis. The gene is expressesd when the polypeptide is formed. This occurs by transcription and translation...(assume you know these steps)
Mechanisms to stop gene expression
- Non-coding segments of DNA (introns) are spliced off the mRNA strand during transcription, as only exons are expressed
- Before transcription genes that are not expressed by the cell will be tightly condensed around the DNA. This prevents the gene ssegment from exposing itself during mRNA synthesis.
- Chemicals maybe secreted to prevent the mRNA strand from successfully binding to the ribosome; thus preventing the gene from being expressed

 

[leesh95]

a) Yes. So If you clone a sheep you would have to grow the embryo in a sheep

b) Hmm.. I did biotech as an option and your explanation is so much more complex then what I learned haha.

This is what our teacher gave us
1) Plasmid of vector bacteria (Agrobacterium Tumerfacienes) removed
2) Desired gene from BT bacteria cut using restriction enzyme.
3)Inserted into plasmid of vector bacteria
4)Plasmid re-inserted in vector bacteria
5)One cotton plant wounded and bacteria allowed to enter it. Thus the re-combinant DNA becomes part of bacteria
6)Plant calluses grown in nutrients and then planted

c) I think you are right except you have to mention that the cells are taken from the root tip of the plant where the undifferentiated stem cells are

 

[SophxMusic]

Just a quick question for Communication...
The structure of the larynx? Is it good enough to know that it contains the vocal cords which are muscles that can vary their length, size and tension to adjust pitch as air is pushed from the lungs via diaphragm action? And this sound can then be modified by the articulators?


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[planino]

- Non-coding segments of DNA (introns) are spliced off the mRNA strand during transcription, as only exons are expressed
- Before transcription genes that are not expressed by the cell will be tightly condensed around the DNA. This prevents the gene ssegment from exposing itself during mRNA synthesis.
- Chemicals maybe secreted to prevent the mRNA strand from successfully binding to the ribosome; thus preventing the gene from being expressed

You've explained this better than 2 textbooks, hsconline and Sir's notes. THANK. YOU. Pls state rank.

And thank you leesh I'll mention root tip instead. And the Bt cotton method clarifies a few things too, but I won't be naming the vector bacteria though haha.

 

[planino]

When Helper T-cells (Th cells) are activated, do the Th cells become cloned as well?
- And if they do, then do some Th cells become killer T cells whilst others become memory T cells?
Interleukin-2 (a cytokine) is released by the activated Th cell and this stimulates B cell cloning. Most B cells become plasma cells whilst some become memory B cells. Is this correct?
Also, when the killer T-cells are activated, they clone themselves. Memory T cells are produced simulataneously, but where do they come from? With B cells, some B cells become the memory B cells, but memory T cells seem to appear out of nowhere.

 

[planino]

(the above was copied from the Biology progression thread)

AND:

It does not have to be the same type of sheep though.

Of course it's a sheep, but by "same type" do you mean that the surrogate doesn't have to be the same species?

 

[leesh95]

I don't remember learning anything about the exact procedure of memory cell formation just that they are produced as the B and T cell clone themselves.

I don't think that much detail is necessary for HSC biology. It's more important to know that they are there and they are important in forming immunity and generating a powerful and quick secondary response upon re-exposure.

Th cells do clone themselves and stimulate cloning of killer T cells.

 

[superSAIyan2]

(the above was copied from the Biology progression thread)

AND:
Of course it's a sheep, but by "same type" do you mean that the surrogate doesn't have to be the same species?

The species is sheep. By type (or breed of sheep) i mean, the clone can be a dorset sheep whilst the surrogate can be a merino.

Regarding your lymphocyte question,
Helper T cells are activated by antigens and stimulate the cloning of B and T ymphocytes by secreting cytokines such as interleukin. Some T lymphocytes will differentiate and become cytotoxic/killer T cells whilst other become memory T cells. Similarly, some B lymphocytes will differentiate and become plasma B cells whilst others become memory B cells. The helper T cells dont need to become cloned as they are only involved in recognising the anitgen as a foreign substance.

 

[superSAIyan2]

You've explained this better than 2 textbooks, hsconline and Sir's notes. THANK. YOU. Pls state rank.

lol thanks good luck tomorrow.

 

[Queenroot]

Invading your thread to ask:

So T&B cells are activated together?

 

[Queenroot]

The t helper cell activate the b cell through stimulating it with fragment of antigen presented.

Yes I know the process. I'm just asking whether it happens at the same time. Like are some T-helper cells activating B cells and some T-helper cells activating T-cells?

 

[planino]

Yes I know the process. I'm just asking whether it happens at the same time. Like are some T-helper cells activating B cells and some T-helper cells activating T-cells?

Yeah they're activated together in a way. Th cells activated ---> release interleukin-2 (a cytokine) ----> activates B cells, which then clone once activated (killer T cells also clone upon activation)

 

[planino]

lol thanks good luck tomorrow.

Ditto!